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Deshpande D, Srivastava S, Gumbo T. Ertapenem's therapeutic potential for Mycobacterium avium lung disease in the hollow fiber model. Int J Antimicrob Agents 2024:107204. [PMID: 38754528 DOI: 10.1016/j.ijantimicag.2024.107204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 04/25/2024] [Accepted: 05/10/2024] [Indexed: 05/18/2024]
Abstract
INTRODUCTION Guideline-based therapy for Mycobacterium avium complex (MAC) pulmonary disease achieves sustained sputum conversion rates in only 43-53% of patients. Repurposing of β-lactam antibiotics such as ertapenem could expedite design of more efficacious regimens, compared to developing new drugs. METHODS We performed an ertapenem exposure-response study in the hollow fiber system model of intracellular MAC (HFS-MAC). We recapitulated human-like intrapulmonary concentration-time profiles of eight once-daily intravenous doses of ertapenem over 28 days and performed repetitive sampling for drug concentration-time profiles and MAC burden. The % of time concentration persisted above MIC (%TMIC) mediating either 50% or 80% of maximal effect (E50, EC80) were identified. The EC80 was used as target exposure in a 10,000 subject Monte Carlo experiments for ertapenem doses of 1G, 2G, or 4G administered once versus twice daily. RESULTS The ertapenem MIC ranged from 0.5 to 2 mg/L on three occasions. Ertapenem achieved a half-life of 4.04±0.80h in the HFS-MAC and killed a maximum of 2.17 log10 CFU/mL below day 0. The EC50 was %TMIC of 75.9% (95% confidence interval: 68.43% to 86.54%) and the EC80 was %TMIC of 100%. Target attainment probability was >90% for 1G twice daily up to an MIC of 2 mg/L, while for 2G twice daily the susceptibility MIC breakpoint was 4-8 mg/L. CONCLUSIONS Ertapenem microbial kill below day 0 burden was better than guideline-based therapy drugs in the HFS-MAC in the past. Ertapenem is a promising drug for novel combination therapies for MAC lung disease.
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Affiliation(s)
| | - Shashikant Srivastava
- Department of Medicine, School of Medicine, the University of Texas at Tyler, Tyler, Texas, USA; Department of Cellular and Molecular Biology, Center for Biomedical Research, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | - Tawanda Gumbo
- Hollow Fiber System & Experimental Therapeutics Laboratories, Irving, Texas, USA; Mathematical Modeling and AI Department, Praedicare Inc., Irving, Texas, USA.
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Deshpande D, Magombedze G, Boorgula GD, Chapagain M, Srivastava S, Gumbo T. Ceftriaxone efficacy for Mycobacterium avium complex lung disease in the hollow fiber and translation to sustained sputum culture conversion in patients. J Infect Dis 2023:jiad545. [PMID: 38036299 DOI: 10.1093/infdis/jiad545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 11/17/2023] [Accepted: 11/28/2023] [Indexed: 12/02/2023] Open
Abstract
BACKGROUND Only 35.6%-50.8% of patients with Mycobacterium avium complex (MAC) pulmonary disease achieve sustained sputum culture conversion (SSCC) on treatment with the azithromycin-ethambutol-rifabutin standard of care (SOC). We tested the efficacy of ceftriaxone, a β-lactam with a lung penetration ratio of 12.18-fold. METHODS We mimicked lung concentration-time profiles of seven ceftriaxone once-daily doses for 28 days in the hollow fiber system model of intracellular MAC (HFS- MAC). Monte Carlo experiments were used for dose selection.We also compared the once-daily ceftriaxone monotherapy to three-drug SOC against five MAC clinical isolates in HFS-MAC using γ (kill)-slopes. Results were translated to SSCC rates. RESULTS Ceftriaxone killed 1.02-3.82 log10 cfu/mL in dose-response studies. Ceftriaxone 2G once-daily was identified as the optimal dose. Ceftriaxone killed all five strains below day 0 versus 2/5 for SOC. The median γ (95% confidence interval) was 0.49(0.47-0.52) log10 cfu/mL/day for ceftriaxone and 0.38(0.34-0.43) log10 cfu/mL/day for SOC. In patients, the SOC was predicted to achieve SSCC rates of 39.3%(36%-42%) at 6 months (similar to meta-analyses results). The SOC SSCC was 50% at 8.18(3.64-27.66) months versus 3.58(2.20-7.23) months for ceftriaxone. Thus, ceftriaxone shortened time-to-SSCC 2.35-fold compared to SOC. CONCLUSION Ceftriaxone is a promising agent for creation of short-course chemotherapy.
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Affiliation(s)
| | - Gesham Magombedze
- Mathematical Modeling and AI Department Praedicare Inc., Dallas, Texas, USA
| | - Gunavanthi D Boorgula
- Department of Medicine, School of Medicine, University of Texas at Tyler, Tyler, Texas, USA
| | - Moti Chapagain
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | - Shashikant Srivastava
- Baylor University Medical Center, Dallas, Texas, USA
- Department of Medicine, School of Medicine, University of Texas at Tyler, Tyler, Texas, USA
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | - Tawanda Gumbo
- Mathematical Modeling and AI Department Praedicare Inc., Dallas, Texas, USA
- Hollow Fiber System & Experimental Therapeutics Laboratories, Praedicare Inc, Dallas, Texas, USA
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Tomar P, Rajoriya JS, Ojha BK, Singh AK, Deshpande D, Choubey P, Raje A, Mishra GK, Perumal P. Tinospora cordifolia modulates the seminal parameters, leakage of intracellular enzymes and seminal antioxidants in equilibrated and cryopreserved semen of Sahiwal bulls. Reprod Domest Anim 2023. [PMID: 37009827 DOI: 10.1111/rda.14352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 03/05/2023] [Accepted: 03/24/2023] [Indexed: 04/04/2023]
Abstract
The present study was undertaken to assess the effects of stem extract of Tinospora cordifolia (Giloy or Guduchi) in the semen extender on seminal parameters, leakage of intracellular enzymes and antioxidants in semen of Sahiwal bull. A total of 48 ejaculates from four bulls were selected for the study. Spermatozoa of 25×106 were incubated in 100, 300 and 500 μg of stem extract of Guduchi as Gr II, III and IV, respectively and pre-freeze and post-thaw semen samples were analysed for seminal parameters (motility, viability, total sperm abnormality; TSA, plasma membrane integrity; PMI, and acrosomal integrity; AcI), intracellular enzymes (aspartate aminotransferase; AST and lactate dehydrogenase; LDH) and seminal antioxidants (superoxide dismutase; SOD and catalase) in comparison with an untreated control group (Gr I). The results revealed that stem extract treated semen had significantly (p<0.05) higher motility, viability, PMI, AcI, SOD and catalase and had significantly (p<0.05) lower TSA, AST and LDH compared to those in untreated control group at pre-freeze and post-thaw stages. Semen treated with 100 μg stem extract /25×106 spermatozoa had significantly (p<0.05) higher motility, viability, PMI, AcI, SOD and catalase and had significantly (p<0.05) lower TSA, AST and LDH compared to those in control, 300, and 500 μg treated groups at pre-freeze and post-thaw stages. Further, these seminal parameters and antioxidants were showing decreasing trend and TSA and leakage of intra-cellular enzymes were showing increasing trend from Gr II to Gr IV at pre-freeze and post-thaw stages. Thus, 100 μg/25×106 spermatozoa were optimum or suitable dose for cryopreservation of Sahiwal bull semen. The study concluded that T. cordifolia stem extract 100 μg/25×106 spermatozoa in the semen extender can be effectively utilized to reduce the oxidative stress and improve the pre-freeze and post-thaw seminal parameters in Sahiwal bull. However, further studies on effects of different concentrations of stem extract on in-vitro or in-vivo fertility trials are to be conducted to assess the impact of the stem extract supplementation in the semen extender on field pregnancy outcome in bovine species.
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Affiliation(s)
- P Tomar
- NDVSU-College of Veterinary Science & Animal Husbandry, Rewa, Madhya Pradesh, India
| | - J S Rajoriya
- NDVSU-College of Veterinary Science & Animal Husbandry, Rewa, Madhya Pradesh, India
| | - B K Ojha
- NDVSU-College of Veterinary Science & Animal Husbandry, Rewa, Madhya Pradesh, India
| | - A K Singh
- NDVSU-College of Veterinary Science & Animal Husbandry, Rewa, Madhya Pradesh, India
| | - D Deshpande
- Central Semen Station, Bhadbhada, Bhopal, Madhya Pradesh, India
| | - P Choubey
- Central Semen Station, Bhadbhada, Bhopal, Madhya Pradesh, India
| | - A Raje
- NDVSU-College of Veterinary Science & Animal Husbandry, Rewa, Madhya Pradesh, India
| | - G K Mishra
- NDVSU-College of Veterinary Science & Animal Husbandry, Rewa, Madhya Pradesh, India
| | - P Perumal
- ICAR-Central, Island Agricultural Research Institute, Port Blair, Andaman and Nicobar Islands
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Gumbo T, Srivastava S, Deshpande D, Pasipanodya JG, Berg A, Romero K, Hermann D, Hanna D. Hollow-fibre system model of tuberculosis reproducibility and performance specifications for best practice in drug and combination therapy development. J Antimicrob Chemother 2023; 78:953-964. [PMID: 36794692 PMCID: PMC10068422 DOI: 10.1093/jac/dkad029] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 01/17/2023] [Indexed: 02/17/2023] Open
Abstract
BACKGROUND The hollow-fibre system model of tuberculosis (HFS-TB) has been endorsed by regulators; however, application of HFS-TB requires a thorough understanding of intra- and inter-team variability, statistical power and quality controls. METHODS Three teams evaluated regimens matching those in the Rapid Evaluation of Moxifloxacin in Tuberculosis (REMoxTB) study, plus two high-dose rifampicin/pyrazinamide/moxifloxacin regimens, administered daily for up to 28 or 56 days against Mycobacterium tuberculosis (Mtb) under log-phase growth, intracellular growth or semidormant growth under acidic conditions. Target inoculum and pharmacokinetic parameters were pre-specified, and the accuracy and bias at achieving these calculated using percent coefficient of variation (%CV) at each sampling point and two-way analysis of variance (ANOVA). RESULTS A total of 10 530 individual drug concentrations, and 1026 individual cfu counts were measured. The accuracy in achieving intended inoculum was >98%, and >88% for pharmacokinetic exposures. The 95% CI for the bias crossed zero in all cases. ANOVA revealed that the team effect accounted for <1% of variation in log10 cfu/mL at each timepoint. The %CV in kill slopes for each regimen and different Mtb metabolic populations was 5.10% (95% CI: 3.36%-6.85%). All REMoxTB arms exhibited nearly identical kill slopes whereas high dose regimens were 33% faster. Sample size analysis revealed that at least three replicate HFS-TB units are needed to identify >20% difference in slope, with a power of >99%. CONCLUSIONS HFS-TB is a highly tractable tool for choosing combination regimens with little variability between teams, and between replicates.
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Affiliation(s)
- Tawanda Gumbo
- Hollow Fiber System & Experimental Therapeutics Laboratories, Praedicare Inc, Dallas, TX, USA.,Quantitative Preclinical and Clinical Sciences Department, Praedicare Inc, Dallas, TX, USA.,Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Shashikant Srivastava
- Hollow Fiber System & Experimental Therapeutics Laboratories, Praedicare Inc, Dallas, TX, USA.,Department of Pulmonary Immunology, University of Texas Health Centre, Tyler, TX, USA
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Jotam G Pasipanodya
- Quantitative Preclinical and Clinical Sciences Department, Praedicare Inc, Dallas, TX, USA.,Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Alexander Berg
- Cognigen Division, Simulations Plus, Inc., Buffalo, NY, USA
| | | | | | - Debra Hanna
- Bill and Melinda Gates Foundation, Seattle, WA, USA
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Deshpande D, Srivastava S, Pasipanodya JG, Gumbo T. Minocycline intra-bacterial pharmacokinetic hysteresis as a basis for pharmacologic memory and a backbone for once-a-week pan-tuberculosis therapy. Front Pharmacol 2022; 13:1024608. [PMID: 36330086 PMCID: PMC9622937 DOI: 10.3389/fphar.2022.1024608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 09/30/2022] [Indexed: 11/24/2022] Open
Abstract
Background: There is need for shorter duration regimens for the treatment of tuberculosis, that can treat patients regardless of multidrug resistance status (pan-tuberculosis). Methods: We combined minocycline with tedizolid, moxifloxacin, and rifampin, in the hollow fiber system model of tuberculosis and mimicked each drugs’ intrapulmonary pharmacokinetics for 28 days. Minocycline-tedizolid was administered either as a once-a-week or a daily regimen. In order to explore a possible explanation for effectiveness of the once-a-week regimen, we measured systemic and intra-bacterial minocycline pharmacokinetics. Standard daily therapy (rifampin, isoniazid, pyrazinamide) was the comparator. We then calculated γf or kill slopes for each regimen and ranked the regimens by time-to-extinction predicted in patients. Results: The steepest γf and shortest time-to-extinction of entire bacterial population was with daily minocycline-rifampin combination. There was no difference in γf between the minocycline-tedizolid once-a-week versus the daily therapy (p = 0.85). Standard therapy was predicted to cure 88% of patients, while minocycline-rifampin would cure 98% of patients. Minocycline concentrations fell below minimum inhibitory concentration after 2 days of once-weekly dosing schedule. The shape of minocycline intra-bacterial concentration-time curve differed from the extracellular pharmacokinetic system and lagged by several days, consistent with system hysteresis. Hysteresis explained the persistent microbial killing after hollow fiber system model of tuberculosis concentrations dropped below the minimum inhibitory concentration. Conclusion: Minocycline could form a backbone of a shorter duration once-a-week pan-tuberculosis regimen. We propose a new concept of post-antibiotic microbial killing, distinct from post-antibiotic effect. We propose system hysteresis as the basis for the novel concept of pharmacologic memory, which allows intermittent dosing.
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Affiliation(s)
| | - Shashikant Srivastava
- Department of Pulmonary Immunology, University of Texas Health Science Center at Tyler, Tyler, TX, United States
| | | | - Tawanda Gumbo
- Quantitative Preclinical and Clinical Sciences Department, Praedicare Inc, Dallas, TX, United States
- Hollow Fiber System and Experimental Therapeutics Laboratories, Praedicare Inc., Dallas, TX, United States
- *Correspondence: Tawanda Gumbo,
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Srivastava S, Deshpande D, Magombedze G, van Zyl J, Cirrincione K, Martin K, Bendet P, Berg A, Hanna D, Romero K, Hermann D, Gumbo T. Duration of pretomanid/moxifloxacin/pyrazinamide therapy compared with standard therapy based on time-to-extinction mathematics. J Antimicrob Chemother 2021; 75:392-399. [PMID: 31713607 PMCID: PMC6966096 DOI: 10.1093/jac/dkz460] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 09/29/2019] [Accepted: 10/08/2019] [Indexed: 01/13/2023] Open
Abstract
Objectives Animal models have suggested that the combination of pretomanid with pyrazinamide and moxifloxacin (PaMZ) may shorten TB therapy duration to 3–4 months. Here, we tested that in the hollow-fibre system model of TB (HFS-TB). Methods A series of HFS-TB experiments were performed to compare the kill rates of the PaMZ regimen with the standard three-drug combination therapy. HFS-TB experiments were performed with bacilli in log-phase growth treated for 28 days, intracellular bacilli treated daily for 28 days and semi-dormant Mycobacterium tuberculosis treated with daily therapy for 56 days for sterilizing effect. Next, time-to-extinction equations were employed, followed by morphism transformation and Latin hypercube sampling, to determine the proportion of patients who achieved a time to extinction of 3, 4 or 6 months with each regimen. Results Using linear regression, the HFS-TB sterilizing effect rates of the PaMZ regimen versus the standard-therapy regimen during the 56 days were 0.18 (95% credible interval=0.13–0.23) versus 0.15 (95% credible interval=0.08–0.21) log10 cfu/mL/day, compared with 0.16 (95% credible interval=0.13–0.18) versus 0.11 (95% credible interval=0.09–0.13) log10 cfu/mL/day in the Phase II clinical trial, respectively. Using time-to-extinction and Latin hypercube sampling modelling, the expected percentages of patients in which the PaMZ regimen would achieve sterilization were 40.37% (95% credible interval=39.1–41.34) and 72.30% (95% credible interval=71.41–73.17) at 3 and 4 months duration of therapy, respectively, versus 93.67% (95% credible interval=93.18–94.13) at 6 months for standard therapy. Conclusions The kill rates of the PaMZ regimen were predicted to be insufficient to achieve cure in less than 6 months in most patients.
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Affiliation(s)
- Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Gesham Magombedze
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Johanna van Zyl
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Kayle Cirrincione
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | | | | | - Alexander Berg
- Critical Path to TB Drug Regimens, Critical Path Institute, Tucson, AZ, USA
| | - Debra Hanna
- Critical Path to TB Drug Regimens, Critical Path Institute, Tucson, AZ, USA.,Bill & Melinda Gates Foundation, Seattle, WA, USA
| | - Klaus Romero
- Critical Path to TB Drug Regimens, Critical Path Institute, Tucson, AZ, USA
| | - Dave Hermann
- Bill & Melinda Gates Foundation, Seattle, WA, USA
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA.,Praedicare Laboratories, Dallas, TX, USA.,Lung Infection and Immunity Unit, Division of Pulmonology and UCT Lung Institute, Department of Medicine, University of Cape Town, Cape Town, South Africa
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Gumbo T, Sherman CM, Deshpande D, Alffenaar JW, Srivastava S. Mycobacterium tuberculosis sterilizing activity of faropenem, pyrazinamide and linezolid combination and failure to shorten the therapy duration. Int J Infect Dis 2021; 104:680-684. [PMID: 33556616 PMCID: PMC8168785 DOI: 10.1016/j.ijid.2021.01.062] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/20/2021] [Accepted: 01/23/2021] [Indexed: 01/26/2023] Open
Abstract
Background: Faropenem (F), an orally bioavailable β-lactam, kills Mycobacterium tuberculosis (Mtb) without the help of a β-lactamase inhibitor. This study explored the sterilizing effect of adding F once or twice daily to a linezolid (L) plus pyrazinamide (Z) backbone regimen. Methods: In vitro studies were performed using the hollow fiber model of tuberculosis (HFS-TB) to compare the kill rates of: 1) ZL two-drug combination; 2) F administered once daily plus ZL (F1ZL); 3) F administered twice-daily plus once daily ZL (F2ZL); 4) F2ZL with high-dose Z (F2ZhiL); 5) standard therapy of isoniazid, rifampin and Z; and 6) non-treated controls. The study was performed over 56 days with three HFS-TB replicates for each regimen. Results: Mtb in the non-treated HFS-TB grew at a rate of 0.018 ± 0.007 log10 CFU/mL/day. The exponential kill rates for standard therapy were 6.6–13.2-fold higher than ZL dual therapy. The F1ZL and F2ZL regimens ranked third. The pre-existing isoniazid-resistant sub-population in the inoculum (1.34 ± 0.57 log10 CFU/mL) grew to 4.21 ± 0.58 log10 CFU/mL in 56 days in non-treated HFS-TB. However, no isoniazid-resistant sub-population was recorded in any of the FZL combination regimens. Conclusion: Due to the slow kill rate compared to standard therapy, FZL regimens are unlikely to shorten therapy duration. Efficacy of these regimens against drug-resistant tuberculosis needs to be determined.
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Affiliation(s)
- Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA; Praedicare Laboratories and Quantitative Preclinical & Clinical Sciences Department, Praedicare Inc., Dallas, TX, USA; Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Carleton M Sherman
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA; Praedicare Laboratories and Quantitative Preclinical & Clinical Sciences Department, Praedicare Inc., Dallas, TX, USA
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Jan-Willem Alffenaar
- The University of Sydney, Faculty of Medicine and Health, School of Pharmacy, Sydney, Australia; Westmead Hospital, Sydney, Australia; Marie Bashir Institute of Infectious Diseases, The University of Sydney, Sydney, Australia
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA; Department of Immunology, UT Southwestern Medical Center, Dallas, TX, USA; Department of Pulmonary Immunology, University of Texas Health Science Centre, Tyler, TX, USA.
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Srivastava S, Chapagain M, van Zyl J, Deshpande D, Gumbo T. Potency of vancomycin against Mycobacterium tuberculosis in the hollow fiber system model. J Glob Antimicrob Resist 2021; 24:403-410. [PMID: 33508482 DOI: 10.1016/j.jgar.2021.01.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 12/11/2020] [Accepted: 01/05/2021] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVES To determine whether an inhaled vancomycin formulation resulting in high intrapulmonary 24-h area under the concentration-time curve (AUC0-24) could be optimised for tuberculosis treatment. We also explored vancomycin synergy and antagonism with d-cycloserine and benzylpenicillin. METHODS We determined MICs of two Mycobacterium tuberculosis (Mtb) laboratory strains (H37Ra and H37Rv) and two drug-susceptible and nine multidrug resistant clinical strains. Second, in the hollow fiber system model of TB [HFS-TB] using Mtb H37Ra strain, we recapitulated vancomycin intrapulmonary pharmacokinetics of eight doses administered twice daily over 28 days, mimicking a 6-h half-life. Using the HFS-TB, vancomycin was tested in combination with d-cycloserine and benzylpenicillin to determine synergy or antagonism between drugs targeting the same pathway. RESULTS Vancomycin MICs were 12 and 48 mg/L in drug-susceptible clinical isolates but >96 mg/L in all MDR isolates.In the HFS-TB, vancomycin killed 3.9 ± 0.6 log10 CFU/mL Mtb. The EC50 was calculated as AUC0-24/MIC of 184.6 ± 106.5. Compared with day 0, 1.0 and 2.0 log10 CFU/mL kill was achieved by AUC0-24/MIC of 168 and 685, respectively. Acquired vancomycin resistance developed to all vancomycin doses tested in the HFS-TB. In the HFS-TB, vancomycin was antagonistic to benzylpenicillin, which works downstream to glycopeptides in peptidoglycan synthesis, but synergistic with d-cycloserine, which inhibits upstream d-Ala-d-Ala ligase and alanine racemase. CONCLUSION Our proof-of-concept studies show that vancomycin optimal exposure target for Mtb kill could be achieved via inhalational drug delivery. Addition of drugs synergistic with vancomycin, e.g. d-cycloserine, may lower the vancomycin concentrations required to kill Mtb.
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Affiliation(s)
- Shashikant Srivastava
- Department of Pulmonary Immunology, University of Texas Health Science Center at Tyler, Tyler, TX, USA; Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Moti Chapagain
- Department of Pulmonary Immunology, University of Texas Health Science Center at Tyler, Tyler, TX, USA; Quantitative Preclinical and Clinical Sciences Department, Praedicare Inc., Dallas, TX, USA
| | - Johanna van Zyl
- Department of Pulmonary Immunology, University of Texas Health Science Center at Tyler, Tyler, TX, USA
| | - Devyani Deshpande
- Department of Pulmonary Immunology, University of Texas Health Science Center at Tyler, Tyler, TX, USA
| | - Tawanda Gumbo
- Department of Pulmonary Immunology, University of Texas Health Science Center at Tyler, Tyler, TX, USA; Quantitative Preclinical and Clinical Sciences Department, Praedicare Inc., Dallas, TX, USA; Lung Infection and Immunity Unit, Division of Pulmonology and UCT Lung Institute, Department of Medicine, University of Cape Town, Cape Town, South Africa.
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Srivastava S, Cirrincione KN, Deshpande D, Gumbo T. Tedizolid, Faropenem, and Moxifloxacin Combination With Potential Activity Against Nonreplicating Mycobacterium tuberculosis. Front Pharmacol 2021; 11:616294. [PMID: 33542690 PMCID: PMC7851080 DOI: 10.3389/fphar.2020.616294] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 11/26/2020] [Indexed: 11/13/2022] Open
Abstract
Background:Mycobacteriumtuberculosis [Mtb] could be present in different metabolic population in the lung lesions, and nonreplicating persisters [NRP], associated with latent tuberculosis [TB], are the most difficult to kill. Objective: Test the combination of tedizolid, moxifloxacin, and faropenem for activity against NRP using Mtb SS18b in the hollow fiber model [HFS-TB]. Methods: Tedizolid and moxifloxacin were tested as, first, two-drug combination against log-phase growth [LPG] and, second, slowly replicating bacilli [SRB] under acidic condition and with faropenem to create a three-drug combination regimen. Finally, standard regimen [isoniazid-rifampin-pyrazinamide] was used as comparator in the HFS-TB experiment with NRP Mtb. HFS-TB units were sampled for drug-concentration measurement as well as for estimation of bacterial burden using solid agar and mycobacterial growth indicator tube [MGIT] method. Linear regression was used to calculate the kill slopes with each treatment regimen and analysis of variance (ANOVA) to compare the regimen. Results: Tedizolid at standard dose in combination with high-dose moxifloxacin killed 3.05 log10 CFU/ml LPG Mtb and 7.37 log10 CFU/ml SRB in the bactericidal and sterilizing activity HFS-TB experiments, respectively. There was no statistical difference between tedizolid-moxifloxacin-faropenem combination and the standard regimen as both killed 7.35 log10 CFU/ml NRP Mtb in 21 days. There was no emergence of resistance to any of the drugs studied in the three HFS-TB experiments. Conclusion: The experimental regimen of tedizolid, moxifloxacin, and faropenem could effectively kill NRP population of Mtb, and given the efficacy against different metabolic population of Mtb could serve as a pan-TB regimen. Clinical studies are warranted to validate the in vitro findings.
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Affiliation(s)
- Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, United States.,Department of Immunology, UT Southwestern Medical Center, Dallas, TX, United States.,Department of Pulmonary Immunology, University of Texas Health Science Center at Tyler, Tyler, TX, United States
| | - Kayle N Cirrincione
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, United States
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, United States
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, United States.,Praedicare Laboratories and Quantitative Preclinical & Clinical Sciences Department Praedicare Inc., Dallas, TX, United States.,Department of Medicine, University of Cape Town, Observatory, Cape Town, South Africa
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Deshpande D, Kuret D, Cirrincione K, Cotroneo N, Melnick D, Lister T, Stokes S, Gumbo T. 1659. Pharmacokinetics/pharmacodynamics of the Novel Gyrase Inhibitor SPR719/SPR720 and Clinical Dose Selection to Treat Pulmonary Mycobacterium avium-complex Disease. Open Forum Infect Dis 2020. [PMCID: PMC7777696 DOI: 10.1093/ofid/ofaa439.1837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Background Current therapy for pulmonary Mycobacterium avium-complex [MAC] disease achieves poor sustained sputum conversion rates and is poorly tolerated. SPR719, the active metabolite of SPR720, a novel gyrase inhibitor, has demonstrated low MICs against MAC. SPR720 is being developed as an oral therapy for use in combination with other antibiotics for the treatment of patients with pulmonary disease due to infection with MAC. Our objective was identify SPR719 pharmacokinetic/pharmacodynamic [PK/PD] parameters and optimal SPR720 dose for treatment of pulmonary MAC. Methods SPR719 was administered once daily for 28 days using a simulated human half-life of 3.3 hours in the hollow fiber system model of pulmonary intracellular MAC [HFS-MAC]. Bacterial burden, including for SPR719-resistant subpopulations, and drug concentrations, were measured via repetitive sampling of HFS-MAC units. A separate dose fractionation study in the HFS-MAC was used to identify the PK/PD index linked to effect. MAC burden versus SPR719 exposure was modeled using the inhibitory sigmoid maximal effect [Emax] model and resistance using the “antibiotic resistance arrow of time” model. Finally, we performed Monte Carlo Experiments to identify the optimal clinical dose of SPR720 monotherapy. Results The median HFS-MAC intracellular-to-extracellular SPR719 AUC0-24 ratio was 2300:1. The PK/PD parameter best linked to microbial kill was determined to be AUC0-24/MIC. SPR719 Emax was -1.5 log10 cfu/mL compared to day 0; 1.0 log10 cfu/mL reduction and acquired-resistance suppression were achieved by an AUC0-24/MIC of 2.0 and 11, respectively. SPR720 1,000 mg/day was predicted to achieve 1.0 log10 cfu/mL kill in 95%, and resistance suppression in 43%, of 10,000 simulated subjects. Conclusion SPR720 monotherapy is predicted to achieve exposures associated with bactericidal effect against pulmonary MAC in 95% of patients at doses that have recently been established to be safe and well tolerated. These data support the continued development of SPR720 for the treatment of pulmonary MAC. Disclosures Nicole Cotroneo, Spero Therapeutics (Employee) David Melnick, MD, Spero Therapeutics (Employee)Spero Therapeutics (Employee) Troy Lister, PhD, Spero Therapeutics (Employee) Suzanne Stokes, PhD, Spero Therapeutics (Employee, Shareholder) Tawanda Gumbo, MD, Praedicare Inc (Employee, Shareholder)
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Affiliation(s)
| | - Daniel Kuret
- Baylor Scott and White Research Institute, Dallas, Texas
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Deshpande D, Chan A, Scalchunes C, Milner J. P257 CHARACTERIZING ASTHMA AMONG ADULTS WITH PRIMARY ANTIBODY DEFICIENCIES: RESULTS FROM A NATIONWIDE PATIENT SURVEY. Ann Allergy Asthma Immunol 2020. [DOI: 10.1016/j.anai.2020.08.135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Ruth MM, Magombedze G, Gumbo T, Bendet P, Sangen JJN, Zweijpfenning S, Hoefsloot W, Pennings L, Koeken VACM, Wertheim HFL, Lee PS, van Ingen J, Deshpande D. Minocycline treatment for pulmonary Mycobacterium avium complex disease based on pharmacokinetics/pharmacodynamics and Bayesian framework mathematical models. J Antimicrob Chemother 2020; 74:1952-1961. [PMID: 31039251 DOI: 10.1093/jac/dkz143] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 02/23/2019] [Accepted: 02/28/2019] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVES Our aim was to identify the pharmacokinetic/pharmacodynamic parameters of minocycline in the hollow-fibre system (HFS) model of pulmonary Mycobacterium avium complex (MAC) and to identify the optimal clinical dose. METHODS Minocycline MICs for 55 MAC clinical isolates from the Netherlands were determined. We also co-incubated primary isolated macrophages infected with MAC with minocycline. Next, we performed a 28 day HFS-MAC model dose-response study in which we mimicked pulmonary concentration-time profiles achieved in patients. The HFS-MAC model was sampled at intervals to determine the minocycline pharmacokinetics and MAC burden. We identified the AUC0-24/MIC ratios associated with 1.0 log10 cfu/mL kill below day 0 (stasis), defined as a bactericidal effect. We then performed 10000 Monte Carlo experiments to identify the optimal dose for a bactericidal effect in patients. RESULTS The MIC for 50% and 90% of cumulative clinical isolates was 8 and 64 mg/L, respectively. Minocycline decreased MAC bacterial burden below stasis in primary isolated macrophages. In the HFS-MAC model, minocycline achieved a microbial kill of 3.6 log10 cfu/mL below stasis. The AUC0-24/MIC exposure associated with a bactericidal effect was 59. Monte Carlo experiments identified a minocycline susceptibility MIC breakpoint of 16 mg/L. At this proposed breakpoint, the clinical dose of 200 mg/day achieved the bactericidal effect exposure target in ∼50% of patients, while 400 mg/day achieved this in 73.6% of patients, in Monte Carlo experiments. CONCLUSIONS Minocycline at a dose of 400 mg/day is expected to be bactericidal. We propose a clinical trial for validation.
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Affiliation(s)
- Mike M Ruth
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Gesham Magombedze
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Paula Bendet
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Jasper J N Sangen
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Sanne Zweijpfenning
- Department of Pulmonary Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Wouter Hoefsloot
- Department of Pulmonary Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Lian Pennings
- Department of Pulmonary Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Valerie A C M Koeken
- Radboud Center for Infectious Diseases, Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Heiman F L Wertheim
- Department of Pulmonary Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Jakko van Ingen
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
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13
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Deshpande D, Magombedze G, Srivastava S, Bendet P, Lee PS, Cirrincione KN, Martin KR, Dheda K, Gumbo T. Once-a-week tigecycline for the treatment of drug-resistant TB. J Antimicrob Chemother 2020; 74:1607-1617. [PMID: 30820554 DOI: 10.1093/jac/dkz061] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 01/17/2019] [Accepted: 01/22/2019] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND MDR-TB and XDR-TB have poor outcomes. OBJECTIVES To examine the efficacy of tigecycline monotherapy in the hollow fibre system model of TB. METHODS We performed pharmacokinetic/pharmacodynamic studies using tigecycline human-like concentration-time profiles in the hollow fibre system model of TB in five separate experiments using Mycobacterium tuberculosis in log-phase growth or as semi-dormant or intracellular bacilli, as monotherapy. We also compared efficacy with the isoniazid/rifampicin/pyrazinamide combination (standard therapy). We then applied extinction mathematics, morphisms and Latin hypercube sampling to identify duration of therapy with tigecycline monotherapy. RESULTS The median tigecycline MIC for 30 M. tuberculosis clinical and laboratory isolates (67% MDR/XDR) was 2 mg/L. Tigecycline monotherapy was highly effective in killing M. tuberculosis in log-phase-growth and semi-dormant and intracellular M. tuberculosis. Once-a-week dosing had the same efficacy as daily therapy for the same cumulative dose; thus, tigecycline efficacy was linked to the AUC0-24/MIC ratio. Tigecycline replacement by daily minocycline after 4 weeks of therapy was effective in sterilizing bacilli. The AUC0-24/MIC ratio associated with optimal kill was 42.3. Tigecycline monotherapy had a maximum sterilizing effect (day 0 minus day 28) of 3.06 ± 0.20 log10 cfu/mL (r2 = 0.92) compared with 3.92 ± 0.45 log10 cfu/mL (r2 = 0.80) with optimized standard therapy. In our modelling, at a tigecycline monotherapy duration of 12 months, the proportion of patients with XDR-TB who reached bacterial population extinction was 64.51%. CONCLUSIONS Tigecycline could cure patients with XDR-TB or MDR-TB who have failed recommended therapy. Once-a-week tigecycline could also replace second-line injectables in MDR-TB regimens.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Gesham Magombedze
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Paula Bendet
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Kayle N Cirrincione
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Katherine R Martin
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Keertan Dheda
- Lung Infection and Immunity Unit, Department of Medicine, Division of Pulmonology and UCT Lung Institute, Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA.,Lung Infection and Immunity Unit, Department of Medicine, Division of Pulmonology and UCT Lung Institute, Department of Medicine, University of Cape Town, Observatory, South Africa
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Deshpande D, Pasipanodya JG, Srivastava S, Martin KR, Athale S, van Zyl J, Antiabong J, Koeuth T, Lee PS, Dheda K, Gumbo T. Minocycline Immunomodulates via Sonic Hedgehog Signaling and Apoptosis and Has Direct Potency Against Drug-Resistant Tuberculosis. J Infect Dis 2020; 219:975-985. [PMID: 30597040 DOI: 10.1093/infdis/jiy587] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 11/14/2018] [Indexed: 11/13/2022] Open
Abstract
Drug-resistant tuberculosis represents a global emergency, requiring new drugs. We found that minocycline was highly potent in laboratory strains of Mycobacterium tuberculosis and that 30 drug-susceptible and multidrug/extensively drug-resistant clinical strains were susceptible to clinically achievable concentrations. In the hollow fiber system model, lung concentration-time profiles of 7 mg/kg/day human-equivalent minocycline dose achieved bacterial kill rates equivalent to those of first-line antituberculosis agents. Minocycline killed extracellular bacilli directly. Minocycline also killed intracellular bacilli indirectly, via concentration-dependent granzyme A-driven apoptosis. Moreover, minocycline demonstrated dose-dependent antiinflammatory activity and downregulation of extracellular matrix-based remodeling pathways and, thus, could protect patients from tuberculosis immunopathology. In RNA sequencing of repetitive samples from the hollow fiber system and in independent protein abundance experiments, minocycline demonstrated dose-dependent inhibition of sonic hedgehog-patched-gli signaling. These findings have implications for improved lung remodeling and for dual immunomodulation and direct microbial kill-based treatment shortening regimens for drug-susceptible and drug-resistant latent and active M. tuberculosis infection.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Katherine R Martin
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Shruti Athale
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Johanna van Zyl
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - John Antiabong
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Thearith Koeuth
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Keertan Dheda
- Division of Pulmonology, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, South Africa
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas.,Division of Pulmonology, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, South Africa
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Pasipanodya JG, Smythe W, Merle CS, Olliaro PL, Deshpande D, Magombedze G, McIlleron H, Gumbo T. Artificial intelligence-derived 3-Way Concentration-dependent Antagonism of Gatifloxacin, Pyrazinamide, and Rifampicin During Treatment of Pulmonary Tuberculosis. Clin Infect Dis 2019; 67:S284-S292. [PMID: 30496458 DOI: 10.1093/cid/ciy610] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Background In the experimental arm of the OFLOTUB trial, gatifloxacin replaced ethambutol in the standard 4-month regimen for drug-susceptible pulmonary tuberculosis. The study included a nested pharmacokinetic (PK) study. We sought to determine if PK variability played a role in patient outcomes. Methods Patients recruited in the trial were followed for 24 months, and relapse ascertained using spoligotyping. Blood was drawn for drug concentrations on 2 separate days during the first 2 months of therapy, and compartmental PK analyses was performed. Failure to attain sustained sputum culture conversion at the end of treatment, relapse, or death during follow-up defined therapy failure. In addition to standard statistical analyses, we utilized an ensemble of machine-learning methods to identify patterns and predictors of therapy failure from among 27 clinical and laboratory features. Results Of 126 patients, 95 (75%) had favorable outcomes and 19 (15%) failed therapy, relapsed, or died. Pyrazinamide and rifampicin peak concentrations and area under the concentration-time curves (AUCs) were ranked higher (more important) than gatifloxacin AUCs. The distribution of individual drug concentrations and their ranking varied significantly between South African and West African trial sites; however, drug concentrations still accounted for 31% and 75% of variance of outcomes, respectively. We identified a 3-way antagonistic interaction of pyrazinamide, gatifloxacin, and rifampicin concentrations. These negative interactions disappeared if rifampicin peak concentration was above 7 mg/L. Conclusions Concentration-dependent antagonism contributed to death, relapse, and therapy failure but was abrogated by high rifampicin concentrations. Therefore, increasing both rifampin and gatifloxacin doses could improve outcomes. Clinical Trials Registration NCT00216385.
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Affiliation(s)
- Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Wynand Smythe
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Corinne S Merle
- Faculty of Epidemiology and Population Health, Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, United Kingdom.,Special Programme on Research and Training in Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Piero L Olliaro
- Special Programme on Research and Training in Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Gesham Magombedze
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Helen McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
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16
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Deshpande D, Pasipanodya JG, Srivastava S, Bendet P, Koeuth T, Bhavnani SM, Ambrose PG, Smythe W, McIlleron H, Thwaites G, Gumusboga M, Van Deun A, Gumbo T. Gatifloxacin Pharmacokinetics/Pharmacodynamics-based Optimal Dosing for Pulmonary and Meningeal Multidrug-resistant Tuberculosis. Clin Infect Dis 2019; 67:S274-S283. [PMID: 30496459 DOI: 10.1093/cid/ciy618] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Background Gatifloxacin is used for the treatment of multidrug-resistant tuberculosis (MDR-TB). The optimal dose is unknown. Methods We performed a 28-day gatifloxacin hollow-fiber system model of tuberculosis (HFS-TB) study in order to identify the target exposures associated with optimal kill rates and resistance suppression. Monte Carlo experiments (MCE) were used to identify the dose that would achieve the target exposure in 10000 adult patients with meningeal or pulmonary MDR-TB. The optimal doses identified were validated using probit analyses of clinical data from 2 prospective clinical trials of patients with pulmonary and meningeal tuberculosis. Classification and regression-tree (CART) analyses were used to identify the gatifloxacin minimum inhibitory concentration (MIC) below which patients failed or relapsed on combination therapy. Results The target exposure associated with optimal microbial kill rates and resistance suppression in the HFS-TB was a 0-24 hour area under the concentration-time curve-to-MIC of 184. MCE identified an optimal gatifloxacin dose of 800 mg/day for pulmonary and 1200 mg/day for meningeal MDR-TB, and a clinical susceptibility breakpoint of MIC ≤ 0.5 mg/L. In clinical trials, CART identified that 79% patients failed therapy if MIC was >2 mg/L, but 98% were cured if MIC was ≤0.5 mg/L. Probit analysis of clinical data demonstrated a >90% probability of a cure in patients if treated with 800 mg/day for pulmonary tuberculosis and 1200 mg/day for meningeal tuberculosis. Doses ≤400 mg/day were suboptimal. Conclusions Gatifloxacin doses of 800 mg/day and 1200 mg/day are recommended for pulmonary and meningeal MDR-TB treatment, respectively. Gatifloxacin has a susceptible dose-dependent zone at MICs 0.5-2 mg/L.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Paula Bendet
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Thearith Koeuth
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | | | - Paul G Ambrose
- Institute for Clinical Pharmacodynamics, Schenectady, New York
| | - Wynand Smythe
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Helen McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Guy Thwaites
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, Churchill Hospital, Oxford, United Kingdom.,Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | | | - Armand Van Deun
- Institute of Tropical Medicine, Antwerp, Belgium.,International Union Against Tuberculosis and Lung Disease, Paris, France
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
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17
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Swamidas J, Phurailatpam R, Panda S, Murthy V, Joshi K, Deshpande D. EP-2083 Evaluation of Deformable Image Registration and Dose Accumulation in Prostate SBRT Patients. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)32503-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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18
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Srivastava S, Deshpande D, Magombedze G, Gumbo T. Efficacy Versus Hepatotoxicity of High-dose Rifampin, Pyrazinamide, and Moxifloxacin to Shorten Tuberculosis Therapy Duration: There Is Still Fight in the Old Warriors Yet! Clin Infect Dis 2018; 67:S359-S364. [PMID: 30496465 PMCID: PMC6260156 DOI: 10.1093/cid/ciy627] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Background One approach that could increase the efficacy and reduce the duration of antituberculosis therapy is pharmacokinetics/pharmacodynamics-based optimization of doses. However, this could increase toxicity. Methods We mimicked the concentration-time profiles achieved by human equivalent doses of moxifloxacin 800 mg/day, rifampin 1800 mg/day, and pyrazinamide 4000 mg/day (high-dose regimen) vs isoniazid 300 mg/day, rifampin 600 mg/day, and pyrazinamide 2000 mg/day (standard therapy) in bactericidal and sterilizing effect studies in the hollow fiber system model of tuberculosis (HFS-TB). In an intracellular Mycobacterium tuberculosis (Mtb) HFS-TB experiment, we added a 3-dimensional human organotypic liver to determine potential hepatotoxicity of the high-dose regimen, based on lactate dehydrogenase (LDH). Treatment lasted 28 days and Mtb bacterial burden was based on colony counts. We calculated the time to extinction (TTE) of the Mtb population in the HFS-TB and used morphism-based transformation and Latin hypercube sampling to identify the minimum therapy duration in patients. Results The kill rate of standard therapy in the bactericidal effect and sterilizing effect experiments were 0.97 (95% confidence interval [CI], .91-.99) log10 colony-forming units (CFU)/mL/day, and 0.56 (95% CI, .49-.59) log10 CFU/mL/day, respectively. The high-dose regimen's bactericidal and sterilizing effect kill rates were 0.99 (95% CI, .96-.99) log10 CFU/mL/day and 0.72 (95% CI, .56-.79) log10 CFU/mL/day, respectively. The upper confidence bound for TTE in patients was 4.5-5 months for standard therapy vs 3.7 months on the high-dose regimen. There were no differences in LDH concentrations between the 2 regimens at any time point (P > .05). Conclusions The high-dose regimen may moderately shorten therapy without increased hepatotoxicity compared to standard therapy.
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Affiliation(s)
- Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Gesham Magombedze
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
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Deshpande D, Srivastava S, Nuermberger E, Koeuth T, Martin KR, Cirrincione KN, Lee PS, Gumbo T. Multiparameter Responses to Tedizolid Monotherapy and Moxifloxacin Combination Therapy Models of Children With Intracellular Tuberculosis. Clin Infect Dis 2018; 67:S342-S348. [PMID: 30496456 PMCID: PMC6260150 DOI: 10.1093/cid/ciy612] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Background Children are often neglected during early development of antituberculosis agents, and most receive treatment after it is first tested in adults. However, very young children have tuberculosis that differs in many respects from adult cavitary pneumonia and could have different toxicity profiles to drugs. Linezolid is effective against intracellular tuberculosis, a common manifestation in young children. However, linezolid has considerable toxicity due to inhibition of mitochondrial enzymes. Tedizolid could be a replacement if it shows equal efficacy and reduced toxicity. Methods We performed tedizolid dose-effect studies in the hollow fiber system model of intracellular tuberculosis. We measured linezolid concentrations, colony-forming units (CFU), time-to-positivity, and monocyte viability and performed RNA sequencing on infected cells collected from repetitive sampling of each system. We also compared efficacy of tedizolid vs linezolid and vs tedizolid-moxifloxacin combination. Results There was no downregulation of mitochondrial enzyme genes, with a tedizolid 0-24 hour area under the concentration-time curve (AUC0-24) of up to 90 mg*h/L. Instead, high exposures led to increased mitochondrial gene expression and monocyte survival. The AUC0-24 to minimum inhibitory concentration ratio associated with 80% of maximal bacterial kill (EC80) was 184 by CFU/mL (r2 = 0.96) and 189 by time-to-positivity (r2 = 0.99). Tedizolid EC80 killed 4.0 log10 CFU/mL higher than linezolid EC80. The tedizolid-moxifloxacin combination had a bacterial burden elimination rate constant of 0.27 ± 0.05 per day. Conclusions Tedizolid demonstrated better efficacy than linezolid, without the mitochondrial toxicity gene or cytotoxicity signatures encountered with linezolid. Tedizolid-moxifloxacin combination had a high bacterial elimination rate.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Eric Nuermberger
- Center for Tuberculosis Research, Department of Medicine
- Department of International Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Thearith Koeuth
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Katherine R Martin
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Kayle N Cirrincione
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
- Department of Medicine, University of Cape Town, Observatory, South Africa
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Deshpande D, Alffenaar JWC, Köser CU, Dheda K, Chapagain ML, Simbar N, Schön T, Sturkenboom MGG, McIlleron H, Lee PS, Koeuth T, Mpagama SG, Banu S, Foongladda S, Ogarkov O, Pholwat S, Houpt ER, Heysell SK, Gumbo T. d-Cycloserine Pharmacokinetics/Pharmacodynamics, Susceptibility, and Dosing Implications in Multidrug-resistant Tuberculosis: A Faustian Deal. Clin Infect Dis 2018; 67:S308-S316. [PMID: 30496460 PMCID: PMC6260153 DOI: 10.1093/cid/ciy624] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Background d-cycloserine is used to treat multidrug-resistant tuberculosis. Its efficacy, contribution in combination therapy, and best clinical dose are unclear, also data on the d-cycloserine minimum inhibitory concentration (MIC) distributions is scant. Methods We performed a systematic search to identify pharmacokinetic and pharmacodynamic studies performed with d-cycloserine. We then performed a combined exposure-effect and dose fractionation study of d-cycloserine in the hollow fiber system model of tuberculosis (HFS-TB). In parallel, we identified d-cycloserine MICs in 415 clinical Mycobacterium tuberculosis (Mtb) isolates from patients. We utilized these results, including intracavitary concentrations, to identify the clinical dose that would be able to achieve or exceed target exposures in 10000 patients using Monte Carlo experiments (MCEs). Results There were no published d-cycloserine pharmacokinetics/pharmacodynamics studies identified. Therefore, we performed new HFS-TB experiments. Cyloserine killed 6.3 log10 colony-forming units (CFU)/mL extracellular bacilli over 28 days. Efficacy was driven by the percentage of time concentration persisted above MIC (%TMIC), with 1.0 log10 CFU/mL kill achieved by %TMIC = 30% (target exposure). The tentative epidemiological cutoff value with the Sensititre MYCOTB assay was 64 mg/L. In MCEs, 750 mg twice daily achieved target exposure in lung cavities of 92% of patients whereas 500 mg twice daily achieved target exposure in 85% of patients with meningitis. The proposed MCE-derived clinical susceptibility breakpoint at the proposed doses was 64 mg/L. Conclusions Cycloserine is cidal against Mtb. The susceptibility breakpoint is 64 mg/L. However, the doses likely to achieve the cidality in patients are high, and could be neurotoxic.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Jan-Willem C Alffenaar
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Claudio U Köser
- Department of Genetics, University of Cambridge, United Kingdom
| | - Keertan Dheda
- Lung Immunity Unit, Division of Pulmonology, Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Moti L Chapagain
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Noviana Simbar
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Thomas Schön
- Department of Infectious Diseases and Clinical Microbiology, Kalmar County Hospital
- Department of Clinical and Experimental Medicine, Division of Medical Microbiology, Linköping University, Sweden
| | - Marieke G G Sturkenboom
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Helen McIlleron
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Thearith Koeuth
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | | | - Sayera Banu
- International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka
| | | | - Oleg Ogarkov
- Scientific Centre of the Family Health and Human Reproduction Problems, Irkutsk, Russian Federation
| | - Suporn Pholwat
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville
| | - Eric R Houpt
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville
| | - Scott K Heysell
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
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Deshpande D, Pasipanodya JG, Mpagama SG, Srivastava S, Bendet P, Koeuth T, Lee PS, Heysell SK, Gumbo T. Ethionamide Pharmacokinetics/Pharmacodynamics-derived Dose, the Role of MICs in Clinical Outcome, and the Resistance Arrow of Time in Multidrug-resistant Tuberculosis. Clin Infect Dis 2018; 67:S317-S326. [PMID: 30496457 PMCID: PMC6260165 DOI: 10.1093/cid/ciy609] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Background Ethionamide is used to treat multidrug-resistant tuberculosis (MDR-TB). The antimicrobial pharmacokinetics/pharmacodynamics, the contribution of ethionamide to the multidrug regimen, and events that lead to acquired drug resistance (ADR) are unclear. Methods We performed a multidose hollow fiber system model of tuberculosis (HFS-TB) study to identify the 0-24 hour area under the concentration-time curve (AUC0-24) to minimum inhibitory concentration (MIC) ratios that achieved maximal kill and ADR suppression, defined as target exposures. Ethionamide-resistant isolates underwent whole-genome and targeted Sanger sequencing. We utilized Monte Carlo experiments (MCEs) to identify ethionamide doses that would achieve the target exposures in 10000 patients with pulmonary tuberculosis. We also identified predictors of time-to-sputum conversion in Tanzanian patients on ethionamide- and levofloxacin-based regimens using multivariate adaptive regression splines (MARS). Results An AUC0-24/MIC >56.2 was identified as the target exposure in the HFS-TB. Early efflux pump induction to ethionamide monotherapy led to simultaneous ethambutol and isoniazid ADR, which abrogated microbial kill of an isoniazid-ethambutol-ethionamide regimen. Genome sequencing of isolates that arose during ethionamide monotherapy revealed mutations in both ethA and embA. In MCEs, 20 mg/kg/day achieved the AUC0-24/MIC >56.2 in >95% of patients, provided the Sensititre assay MIC was <2.5 mg/L. In the clinic, MARS revealed that ethionamide Sensititre MIC had linear negative relationships with time-to-sputum conversion until an MIC of 2.5 mg/L, above which patients with MDR-TB failed combination therapy. Conclusions Ethionamide is an important contributor to MDR-TB treatment regimens, at Sensititre MIC <2.5 mg/L. Suboptimal ethionamide exposures led to efflux pump-mediated ADR.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | | | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Paula Bendet
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Thearith Koeuth
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Scott K Heysell
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
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Srivastava S, Deshpande D, Nuermberger E, Lee PS, Cirrincione K, Dheda K, Gumbo T. The Sterilizing Effect of Intermittent Tedizolid for Pulmonary Tuberculosis. Clin Infect Dis 2018; 67:S336-S341. [PMID: 30496463 PMCID: PMC6260152 DOI: 10.1093/cid/ciy626] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Background Linezolid exhibits remarkable sterilizing effect in tuberculosis; however, a large proportion of patients develop serious adverse events. The congener tedizolid could have a better side-effect profile, but its sterilizing effect potential is unknown. Methods We performed a 42-day tedizolid exposure-effect and dose-fractionation study in the hollow fiber system model of tuberculosis for sterilizing effect, using human-like intrapulmonary pharmacokinetics. Bacterial burden was examined using time to positivity (TTP) and colony-forming units (CFUs). Exposure-effect was examined using the inhibitory sigmoid maximal kill model. The exposure mediating 80% of maximal kill (EC80) was defined as the target exposure, and the lowest dose to achieve EC80 was identified in 10000-patient Monte Carlo experiments. The dose was also examined for probability of attaining concentrations associated with mitochondrial enzyme inhibition. Results At maximal effect, tedizolid monotherapy totally eliminated 7.1 log10 CFU/mL Mycobacterium tuberculosis over 42 days; however, TTP still demonstrated some growth. Once-weekly tedizolid regimens killed as effectively as daily regimens, with an EC80 free drug 0- to 24-hour area under the concentration-time curve-to-minimum inhibitory concentration (MIC) ratio of 200. An oral tedizolid of 200 mg/day achieved the EC80 in 92% of 10000 patients. The susceptibility breakpoint was an MIC of 0.5 mg/L. The 200 mg/day dose did not achieve concentrations associated with mitochondrial enzyme inhibition. Conclusions Tedizolid exhibits dramatic sterilizing effect and should be examined for pulmonary tuberculosis. A tedizolid dose of 200 mg/day or 700 mg twice a week is recommended for testing in patients; the intermittent tedizolid dosing schedule could be much safer than daily linezolid.
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Affiliation(s)
- Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Eric Nuermberger
- Center for Tuberculosis Research, Department of Medicine
- Department of International Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Kayle Cirrincione
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Keertan Dheda
- Lung Infection and Immunity Unit, Division of Pulmonology and University of Cape Town Lung Institute, Department of Medicine, Observatory, South Africa
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
- Lung Infection and Immunity Unit, Division of Pulmonology and University of Cape Town Lung Institute, Department of Medicine, Observatory, South Africa
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Deshpande D, Pasipanodya JG, Mpagama SG, Bendet P, Srivastava S, Koeuth T, Lee PS, Bhavnani SM, Ambrose PG, Thwaites G, Heysell SK, Gumbo T. Levofloxacin Pharmacokinetics/Pharmacodynamics, Dosing, Susceptibility Breakpoints, and Artificial Intelligence in the Treatment of Multidrug-resistant Tuberculosis. Clin Infect Dis 2018; 67:S293-S302. [PMID: 30496461 PMCID: PMC6260169 DOI: 10.1093/cid/ciy611] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Background Levofloxacin is used for the treatment of multidrug-resistant tuberculosis; however the optimal dose is unknown. Methods We used the hollow fiber system model of tuberculosis (HFS-TB) to identify 0-24 hour area under the concentration-time curve (AUC0-24) to minimum inhibitory concentration (MIC) ratios associated with maximal microbial kill and suppression of acquired drug resistance (ADR) of Mycobacterium tuberculosis (Mtb). Levofloxacin-resistant isolates underwent whole-genome sequencing. Ten thousands patient Monte Carlo experiments (MCEs) were used to identify doses best able to achieve the HFS-TB-derived target exposures in cavitary tuberculosis and tuberculous meningitis. Next, we used an ensemble of artificial intelligence (AI) algorithms to identify the most important predictors of sputum conversion, ADR, and death in Tanzanian patients with pulmonary multidrug-resistant tuberculosis treated with a levofloxacin-containing regimen. We also performed probit regression to identify optimal levofloxacin doses in Vietnamese tuberculous meningitis patients. Results In the HFS-TB, the AUC0-24/MIC associated with maximal Mtb kill was 146, while that associated with suppression of resistance was 360. The most common gyrA mutations in resistant Mtb were Asp94Gly, Asp94Asn, and Asp94Tyr. The minimum dose to achieve target exposures in MCEs was 1500 mg/day. AI algorithms identified an AUC0-24/MIC of 160 as predictive of microbiologic cure, followed by levofloxacin 2-hour peak concentration and body weight. Probit regression identified an optimal dose of 25 mg/kg as associated with >90% favorable response in adults with pulmonary tuberculosis. Conclusions The levofloxacin dose of 25 mg/kg or 1500 mg/day was adequate for replacement of high-dose moxifloxacin in treatment of multidrug-resistant tuberculosis.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | | | - Paula Bendet
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Thearith Koeuth
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | | | - Paul G Ambrose
- Institute for Clinical Pharmacodynamics, Schenectady, New York
| | - Guy Thwaites
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, Churchill Hospital, Oxford, United Kingdom
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Scott K Heysell
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
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Magombedze G, Pasipanodya JG, Srivastava S, Deshpande D, Visser ME, Chigutsa E, McIlleron H, Gumbo T. Transformation Morphisms and Time-to-Extinction Analysis That Map Therapy Duration From Preclinical Models to Patients With Tuberculosis: Translating From Apples to Oranges. Clin Infect Dis 2018; 67:S349-S358. [PMID: 30496464 PMCID: PMC6260172 DOI: 10.1093/cid/ciy623] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Background A major challenge in medicine is translation of preclinical model findings to humans, especially therapy duration. One major example is recent shorter-duration therapy regimen failures in tuberculosis. Methods We used set theory mapping to develop a computational/modeling framework to map the time it takes to extinguish the Mycobacterium tuberculosis population on chemotherapy from multiple hollow fiber system model of tuberculosis (HFS-TB) experiments to that observed in patients. The predictive accuracy of the derived translation transformations was then tested using data from 108 HFS-TB Rapid Evaluation of Moxifloxacin in Tuberculosis (REMoxTB) units, including 756 colony-forming units (CFU)/mL. Derived transformations, and Latin hypercube sampling-guided simulations were used to predict cure and relapse after 4 and 6 months of therapy. Outcomes were compared to observations, in 1932 patients in the REMoxTB clinical trial. Results HFS-TB serial bacillary burden and serial sputum data in the derivation dataset formed a structure-preserving map. Bactericidal effect was mapped with a single step transformation, while the sterilizing effect was mapped with a 3-step transformation function. Using the HFS-TB REMoxTB data, we accurately predicted the proportion of patients cured in the 4-month REMoxTB clinical trial. Model-predicted vs clinical trial observations were (i) the ethambutol arm (77.0% [95% confidence interval {CI}, 74.4%-79.6%] vs 77.7% [95% CI, 74.3%-80.9%]) and (ii) the isoniazid arm (76.4% [95% CI, 73.9%-79.0%] vs 79.5% [95% CI, 76.1%-82.5%]). Conclusions We developed a method to translate duration of therapy outcomes from preclinical models to tuberculosis patients.
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Affiliation(s)
- Gesham Magombedze
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Marianne E Visser
- Division of Pharmacology, Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Emmanuel Chigutsa
- Division of Pharmacology, Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Helen McIlleron
- Division of Pharmacology, Department of Medicine, University of Cape Town, Observatory, South Africa
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
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Deshpande D, Phan H, Borgstrom M, Miller R, Brown M. CAREGIVER KNOWLEDGE AS A PREDICTOR OF LENGTH OF STAY IN CHILDREN HOSPITALIZED WITH ASTHMA EXACERBATIONS. Ann Allergy Asthma Immunol 2018. [DOI: 10.1016/j.anai.2018.09.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Deshpande D, Srivastava S, Bendet P, Martin KR, Cirrincione KN, Lee PS, Pasipanodya JG, Dheda K, Gumbo T. Antibacterial and Sterilizing Effect of Benzylpenicillin in Tuberculosis. Antimicrob Agents Chemother 2018; 62:e02232-17. [PMID: 29180526 PMCID: PMC5786797 DOI: 10.1128/aac.02232-17] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Accepted: 11/21/2017] [Indexed: 01/10/2023] Open
Abstract
The modern chemotherapy era started with Fleming's discovery of benzylpenicillin. He demonstrated that benzylpenicillin did not kill Mycobacterium tuberculosis In this study, we found that >64 mg/liter of static benzylpenicillin concentrations killed 1.16 to 1.43 log10 CFU/ml below starting inoculum of extracellular and intracellular M. tuberculosis over 7 days. When we added the β-lactamase inhibitor avibactam, benzylpenicillin maximal kill (Emax) of extracellular log-phase-growth M. tuberculosis was 6.80 ± 0.45 log10 CFU/ml at a 50% effective concentration (EC50) of 15.11 ± 2.31 mg/liter, while for intracellular M. tuberculosis it was 2.42 ± 0.14 log10 CFU/ml at an EC50 of 6.70 ± 0.56 mg/liter. The median penicillin (plus avibactam) MIC against South African clinical M. tuberculosis strains (80% either multidrug or extensively drug resistant) was 2 mg/liter. We mimicked human-like benzylpenicillin and avibactam concentration-time profiles in the hollow-fiber model of tuberculosis (HFS-TB). The percent time above the MIC was linked to effect, with an optimal exposure of ≥65%. At optimal exposure in the HFS-TB, the bactericidal activity in log-phase-growth M. tuberculosis was 1.44 log10 CFU/ml/day, while 3.28 log10 CFU/ml of intracellular M. tuberculosis was killed over 3 weeks. In an 8-week HFS-TB study of nonreplicating persistent M. tuberculosis, penicillin-avibactam alone and the drug combination of isoniazid, rifampin, and pyrazinamide both killed >7.0 log10 CFU/ml. Monte Carlo simulations of 10,000 preterm infants with disseminated disease identified an optimal dose of 10,000 U/kg (of body weight)/h, while for pregnant women or nonpregnant adults with pulmonary tuberculosis the optimal dose was 25,000 U/kg/h, by continuous intravenous infusion. Penicillin-avibactam should be examined for effect in pregnant women and infants with drug-resistant tuberculosis, to replace injectable ototoxic and teratogenic second-line drugs.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas, USA
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas, USA
| | - Paula Bendet
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas, USA
| | - Katherine R Martin
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas, USA
| | - Kayle N Cirrincione
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas, USA
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas, USA
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas, USA
| | - Keertan Dheda
- Lung Infection and Immunity Unit, Division of Pulmonology and UCT Lung Institute, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas, USA
- Lung Infection and Immunity Unit, Division of Pulmonology and UCT Lung Institute, Department of Medicine, University of Cape Town, Cape Town, South Africa
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Abstract
Objectives To identify the pharmacokinetic/pharmacodynamic parameters and exposures of linezolid in the treatment of pulmonary Mycobacterium avium complex (MAC) disease. Methods Human-derived monocytes infected with MAC were inoculated into hollow-fibre systems for dose-effect and dose-scheduling studies. We mimicked linezolid concentration-time profiles achieved in adult human lungs treated for 28 days. Sampling to confirm that the intended linezolid pharmacokinetics had been achieved, and for enumeration of MAC colony-forming units, was performed based on repetitive sampling from each system over the 28 days. We then performed 10 000 patient Monte Carlo simulations to identify doses associated with optimal effect in the clinic. Results Linezolid achieved a hitherto unprecedented feat of at least 1.0 log10 cfu/mL reduction. Efficacy was most closely linked to the AUC0-24/MIC ratio. The AUC0-24/MIC ratio associated with no change in bacterial burden or bacteriostasis was 7.82, while that associated with 1.0 log10 cfu/mL kill was 42.06. The clinical dose of 600 mg/day achieved or exceeded the bacteriostasis exposure in 98.73% of patients. The proportion of 10 000 patients treated with the standard 1200 mg/day who achieved the exposure for 1.0 log10 cfu/mL kill was 70.64%, but was 90% for 1800 mg/day. The proposed MIC breakpoint for linezolid is 16 mg/L, with which 49%-80% of clinical isolates would be considered resistant. Conclusions Linezolid is associated with a bactericidal effect in pulmonary MAC that is greater than that seen with other recommended drugs. However, because of the MIC distribution, doses that would optimize the bactericidal effect would be associated with a high adverse event rate.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
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Deshpande D, Srivastava S, Gumbo T. A programme to create short-course chemotherapy for pulmonary Mycobacterium avium disease based on pharmacokinetics/pharmacodynamics and mathematical forecasting. J Antimicrob Chemother 2018; 72:i54-i60. [PMID: 28922811 DOI: 10.1093/jac/dkx309] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Objectives Pulmonary Mycobacterium avium complex (MAC) prevalence is on the rise worldwide. The average therapy duration is 1.5 years, which is associated with poor cure rates. Our objective was to develop a programme to design a combination therapy regimen for pulmonary MAC to be administered for 6 months or less with efficacy in > 90% of patients. Methods We performed a literature search for the following MeSH headings 'Mycobacterium avium' AND 'pharmacokinetics/pharmacodynamics' in PubMed up to 2016. The findings were then used to identify steps in the programme to design new regimens with faster microbial kill rates than the current standard regimen. Results First, we designed a strategy for rapid in vitro screening of all antibiotic classes for repurposing against pulmonary MAC. Secondly, we identified and compared maximal microbial kill rates (Emax), and optimal exposures of eight different antibiotics. These studies had all been performed in the hollow-fibre system model of pulmonary MAC (HFS-MAC). Thirdly, all drugs with a high Emax at clinically achievable optimal exposures will be chosen, and exposures associated with synergy or additivity for two/three drugs identified based on Bliss independence. Fourthly, the time-kill slopes and resistance suppression of the chosen combinations will be compared with those of standard combination therapy in the HFS-MAC. Finally, we will identify the clinical doses best able to achieve synergistic or additive combination exposures by taking into account pharmacokinetic variability. Conclusions Our stepwise pharmacokinetics/pharmacodynamics approach provides a scientific rationale and a strategy for achieving short-course chemotherapy for pulmonary MAC disease within a few years.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
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Srivastava S, Deshpande D, Sherman CM, Gumbo T. A 'shock and awe' thioridazine and moxifloxacin combination-based regimen for pulmonary Mycobacterium avium-intracellulare complex disease. J Antimicrob Chemother 2018; 72:i43-i47. [PMID: 28922810 DOI: 10.1093/jac/dkx308] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Objectives To develop a thioridazine/moxifloxacin-based combination regimen for treatment of pulmonary infection due to Mycobacterium avium-intracellulare complex (MAC) that kills bacteria faster than the standard treatment regimen. Methods Monocytes were infected with MAC and inoculated into the hollow-fibre system model for pulmonary MAC disease (HFS-MAC). We co-administered ethambutol plus azithromycin daily for 28 days, to achieve the same human concentration-time profiles that result from standard doses, in three HFS-MAC systems. Two experimental regimens consisted of thioridazine at an exposure associated with optimal kill, given intermittently on days 0, 3, 7 and 10. Regimen A consisted of thioridazine in combination with standard dose azithromycin for the entire study duration. Regimen B was thioridazine plus moxifloxacin at concentration-time profiles achieved by the standard daily dose administered for 14 days, followed by daily azithromycin. Each HFS-MAC was sampled for bacterial burden every 7 days. Results The bacteria in the non-treated HFS-MAC grew at a rate of 0.11 ± 0.01 log10 cfu/mL/day. The azithromycin/ethambutol regimen decreased bacterial burden by 1.21 ± 0.74 log10 cfu/mL below baseline during the first 7 days, after which it failed. Regimen A killed 3.28 ± 0.32 log10 cfu/mL below baseline up to day 14, after which regrowth occurred once thioridazine treatment stopped. Regimen B killed bacteria to below the limits of detection in 7 days (≥5.0 log10 cfu/mL kill), with rebound in the azithromycin continuation phase. Conclusions The thioridazine/moxifloxacin regimen demonstrated that rapid microbial kill could be achieved within 7 days. This is a proof of principle that short-course chemotherapy for pulmonary MAC is possible.
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Affiliation(s)
- Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Carleton M Sherman
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
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Deshpande D, Srivastava S, Pasipanodya JG, Lee PS, Gumbo T. Tedizolid is highly bactericidal in the treatment of pulmonary Mycobacterium avium complex disease. J Antimicrob Chemother 2018; 72:i30-i35. [PMID: 28922807 DOI: 10.1093/jac/dkx305] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Objectives To determine if tedizolid is effective for pulmonary Mycobacterium avium complex (MAC) disease, and to use pharmacokinetics/pharmacodynamics to design optimal doses. Methods We performed an exposure-response experiment in the hollow-fibre system model of intracellular MAC (HFS-MAC). We mimicked the tedizolid concentration-time profiles achieved in the lungs of patients treated once daily for 28 days. The HFS-MAC was sampled at intervals to determine the tedizolid pharmacokinetics and MAC intracellular burden. We identified the 0-24 h area under the concentration-time curves to MIC (AUC0-24/MIC) ratios associated with the following targets: 80% of maximal kill (EC80), bacteriostasis, and 1.0 and 2.0 log10 cfu/mL kill. We then performed 10 000 patient Monte Carlo simulations to identify the optimal dose for each of the exposure targets. Results Tedizolid achieved the feat of 2.0 log10 cfu/mL kill below initial bacterial burden, an effect not seen before in this model with other antibiotics. The tedizolid exposure associated with 1.0 log10 cfu/mL kill was a non-protein bound AUC0-24/MIC ratio of 23.46, while that associated with 2.0 log10 cfu/mL kill was 37.50, and the EC80 was 21.71. The clinical dose of 200 mg achieved each of these targets in ∼100% of the 10 000 patients, except the 2.0 log10 cfu/mL kill which required 300 mg/day. A tedizolid susceptibility MIC breakpoint of 1 mg/L is proposed. Conclusions Tedizolid, at standard clinical doses, is expected to be bactericidal, and even achieved an unprecedented 2.0 log10 cfu/mL kill of MAC as monotherapy. We propose it as the backbone of short-course anti-MAC chemotherapy.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
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Pasipanodya JG, Ogbonna D, Deshpande D, Srivastava S, Gumbo T. Meta-analyses and the evidence base for microbial outcomes in the treatment of pulmonary Mycobacterium avium-intracellulare complex disease. J Antimicrob Chemother 2018; 72:i3-i19. [PMID: 28922813 DOI: 10.1093/jac/dkx311] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Objectives To perform a systematic review and meta-analysis of the level of funding support and the sputum culture conversion rates in pulmonary Mycobacterium avium-intracellulare complex (P-MAC) disease in adult patients without cystic fibrosis or HIV infection, treated with recommended antibiotic regimens. Methods We performed a literature search to identify clinical trials, prospective studies and registries that reported outcomes in P-MAC patients. Studies that reported P-MAC diagnosis and treatments based on established guidelines met the inclusion criteria and were examined for bias and quality. We modified existing quality scales and came up with a 10 star quality score. Outcomes meta-analysed were sputum conversion incidence ratios (IR) and their 95% CI, weighted for study quality. Results Twenty-one studies that examined 28 regimens, including 2534 patients in intent-to-treat analyses and 1968 in per-protocol analyses, were identified. The study quality mean ± SD scores were 5.4 ± 2.2 out of 10 stars. Only two (9.5%) studies received public funding. There was significant heterogeneity of microbial effect among treatment regimens (I2 > 40%; P > 0.001). The pooled IR for sustained sputum conversion was 0.54 (95% CI 0.45-0.63) for macrolide-containing regimens versus 0.38 (0.25-0.52) with macrolide-free regimens. Prolonging therapy duration beyond 12 months was associated with an average decline in sputum conversion to 22% (95% CI 1%-44%). Conclusions Researchers working on P-MAC therapy have received very little public funding support. As a result, the evidence base for treatment guidelines is based on studies of relatively small numbers of patients in low-quality studies. Nevertheless, these studies showed poor sputum conversion rates in patients receiving recommended treatment regimens.
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Affiliation(s)
- Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Deborah Ogbonna
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
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Deshpande D, Srivastava S, Pasipanodya JG, Lee PS, Gumbo T. A novel ceftazidime/avibactam, rifabutin, tedizolid and moxifloxacin (CARTM) regimen for pulmonary Mycobacterium avium disease. J Antimicrob Chemother 2018; 72:i48-i53. [PMID: 28922809 DOI: 10.1093/jac/dkx307] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Objectives To compare the efficacy of ceftazidime/avibactam plus tedizolid-based combination regimens with the standard therapy of azithromycin, ethambutol and rifabutin for the treatment of pulmonary Mycobacterium avium complex (MAC) disease. Methods We mimicked the human pulmonary concentration-time profiles of ceftazidime/avibactam and tedizolid in combination, ceftazidime/avibactam, rifabutin, tedizolid and moxifloxacin (CARTM), and the standard regimen and examined microbial kill in triplicate hollow-fibre system model of intracellular pulmonary MAC (HFS-MAC) units. The tedizolid and moxifloxacin doses used were non-optimized; the tedizolid dose was that associated with bacteriostasis. Drugs were administered daily for 28 days. Each HFS-MAC was sampled in the central and peripheral compartment to ascertain that the intended drug exposures had been achieved. The peripheral compartments were sampled at regular intervals over the 28 days to quantify the burden of MAC. Results MAC-infected macrophages in the HFS-MAC achieved multi-fold higher intracellular versus extracellular concentrations of rifabutin, moxifloxacin, ceftazidime/avibactam. The non-optimized ceftazidime/avibactam plus tedizolid dual therapy held the bacterial burden at the same level as day 0 (stasis) throughout the 28 days. The standard therapy reduced the bacterial load 2 log10 cfu/mL below stasis on day 14 but started failing after that. The CARTM regimen achieved 3.2 log10 cfu/mL kill below stasis on day 21, but had started to fail by day 28. Conclusions The CARTM regimen promises to have kill rates better than standard therapy. Experiments to identify exposures of each of the four drugs associated with optimal effect in the CARTM combination are needed in order to design a short-course chemotherapy regimen.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
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Srivastava S, Deshpande D, Gumbo T. Failure of the azithromycin and ethambutol combination regimen in the hollow-fibre system model of pulmonary Mycobacterium avium infection is due to acquired resistance. J Antimicrob Chemother 2018; 72:i20-i23. [PMID: 28922805 DOI: 10.1093/jac/dkx303] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Objectives To investigate the performance of the two backbone drugs in the standard combination therapy regimen in the hollow-fibre system (HFS) model of pulmonary Mycobacterium avium complex (MAC) infection. Methods Six HFS were inoculated with human-derived monocytes infected with MAC, and treated with 15 mg/kg of ethambutol and 500 mg of azithromycin daily for 28 days to recapitulate the concentration-time profiles seen in the lungs of humans treated with these drugs and doses. The concentration-time profiles achieved were validated by sampling the central compartment at seven timepoints over 24 h. The total MAC burden, as well as the subpopulation resistant to 3 × MIC of each drug, was identified based on sampling the peripheral compartment of each system on days 0, 3, 7, 14, 21 and 28 of therapy. The experiment was performed twice. Results In non-treated control HFS, MAC grew from 5.0 to 8.53 log10 cfu/mL in 28 days. The dual therapy killed a maximum of 1.52 ± 0.43 log10 cfu/mL during the first 7 days, after which it failed. By day 28 there was no difference in MAC burden between the combination-therapy-treated and non-treated systems. Failure arose in parallel with the emergence of acquired ethambutol resistance. By day 28, 100% of the bacterial population was ethambutol resistant in the combination-therapy-treated HFS replicates. Conclusions The backbone combination of macrolide and ethambutol has poor MAC kill rates and is ineffective. Microbial kill is rapidly abrogated by acquired drug resistance. This backbone should be replaced.
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Affiliation(s)
- Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA.,Department of Medicine, University of Cape Town, Observatory, Cape Town, South Africa
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Srivastava S, Deshpande D, Pasipanodya JG, Thomas T, Swaminathan S, Nuermberger E, Gumbo T. A Combination Regimen Design Program Based on Pharmacodynamic Target Setting for Childhood Tuberculosis: Design Rules for the Playground. Clin Infect Dis 2017; 63:S75-S79. [PMID: 27742637 PMCID: PMC5064153 DOI: 10.1093/cid/ciw472] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Children with tuberculosis are treated with drug regimens copied from adults despite significant differences in antibiotic pharmacokinetics, pathology, and the microbial burden between childhood and adult tuberculosis. We sought to develop a new and effective oral treatment regimen specific to children of different ages. We investigated and validated the concept that target drug concentrations associated with therapy failure and death in children are different from those of adults. On that basis, we proposed a 4-step program to rapidly develop treatment regimens for children. First, target drug concentrations for optimal efficacy are derived from preclinical models of disseminated tuberculosis that recapitulate pediatric pharmacokinetics, starting with monotherapy. Second, 2-drug combinations were examined for zones of synergy, antagonism, and additivity based on a whole exposure–response surface. Exposures associated with additivity or synergy were then combined and the regimen was compared to standard therapy. Third, several exposures of the third drug were added, and a 3-drug regimen was identified based on kill slopes in comparison to standard therapy. Fourth, computer-aided clinical trial simulations are used to identify clinical doses that achieve these kill rates in children in different age groups. The proposed program led to the development of a 3-drug combination regimen for children from scratch, independent of adult regimens, in <2 years. The regimens and doses can be tested in animal models and in clinical trials.
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Affiliation(s)
- Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Tania Thomas
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville
| | | | - Eric Nuermberger
- Department of International Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas Department of Medicine, University of Cape Town, Observatory, South Africa
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Swaminathan S, Pasipanodya JG, Ramachandran G, Hemanth Kumar AK, Srivastava S, Deshpande D, Nuermberger E, Gumbo T. Drug Concentration Thresholds Predictive of Therapy Failure and Death in Children With Tuberculosis: Bread Crumb Trails in Random Forests. Clin Infect Dis 2017; 63:S63-S74. [PMID: 27742636 PMCID: PMC5064152 DOI: 10.1093/cid/ciw471] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Background. The role of drug concentrations in clinical outcomes in children with tuberculosis is unclear. Target concentrations for dose optimization are unknown. Methods. Plasma drug concentrations measured in Indian children with tuberculosis were modeled using compartmental pharmacokinetic analyses. The children were followed until end of therapy to ascertain therapy failure or death. An ensemble of artificial intelligence algorithms, including random forests, was used to identify predictors of clinical outcome from among 30 clinical, laboratory, and pharmacokinetic variables. Results. Among the 143 children with known outcomes, there was high between-child variability of isoniazid, rifampin, and pyrazinamide concentrations: 110 (77%) completed therapy, 24 (17%) failed therapy, and 9 (6%) died. The main predictors of therapy failure or death were a pyrazinamide peak concentration <38.10 mg/L and rifampin peak concentration <3.01 mg/L. The relative risk of these poor outcomes below these peak concentration thresholds was 3.64 (95% confidence interval [CI], 2.28–5.83). Isoniazid had concentration-dependent antagonism with rifampin and pyrazinamide, with an adjusted odds ratio for therapy failure of 3.00 (95% CI, 2.08–4.33) in antagonism concentration range. In regard to death alone as an outcome, the same drug concentrations, plus z scores (indicators of malnutrition), and age <3 years, were highly ranked predictors. In children <3 years old, isoniazid 0- to 24-hour area under the concentration-time curve <11.95 mg/L × hour and/or rifampin peak <3.10 mg/L were the best predictors of therapy failure, with relative risk of 3.43 (95% CI, .99–11.82). Conclusions. We have identified new antibiotic target concentrations, which are potential biomarkers associated with treatment failure and death in children with tuberculosis.
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Affiliation(s)
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | | | | | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas
| | - Eric Nuermberger
- Center for Tuberculosis Research, Department of Medicine Department of International Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Dallas, Texas Department of Medicine, University of Cape Town, Observatory, South Africa
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Srivastava S, Deshpande D, Pasipanodya J, Nuermberger E, Swaminathan S, Gumbo T. Optimal Clinical Doses of Faropenem, Linezolid, and Moxifloxacin in Children With Disseminated Tuberculosis: Goldilocks. Clin Infect Dis 2017; 63:S102-S109. [PMID: 27742641 PMCID: PMC5064158 DOI: 10.1093/cid/ciw483] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Background. When treated with the same antibiotic dose, children achieve different 0- to 24-hour area under the concentration-time curves (AUC0–24) because of maturation and between-child physiological variability on drug clearance. Children are also infected by Mycobacterium tuberculosis isolates with different antibiotic minimum inhibitory concentrations (MICs). Thus, each child will achieve different AUC0–24/MIC ratios when treated with the same dose. Methods. We used 10 000-subject Monte Carlo experiments to identify the oral doses of linezolid, moxifloxacin, and faropenem that would achieve optimal target exposures associated with optimal efficacy in children with disseminated tuberculosis. The linezolid and moxifloxacin exposure targets were AUC0–24/MIC ratios of 62 and 122, and a faropenem percentage of time above MIC >60%, in combination therapy. A linezolid AUC0–24 of 93.4 mg × hour/L was target for toxicity. Population pharmacokinetic parameters of each drug and between-child variability, as well as MIC distribution, were used, and the cumulative fraction of response (CFR) was calculated. We also considered drug penetration indices into meninges, bone, and peritoneum. Results. The linezolid dose of 15 mg/kg in full-term neonates and infants aged up to 3 months and 10 mg/kg in toddlers, administered once daily, achieved CFR ≥ 90%, with <10% achieving linezolid AUC0–24 associated with toxicity. The moxifloxacin dose of 25 mg/kg/day achieved a CFR > 90% in infants, but the optimal dose was 20 mg/kg/day in older children. The faropenem medoxomil optimal dosage was 30 mg/kg 3–4 times daily. Conclusions. The regimen and doses of linezolid, moxifloxacin, and faropenem identified are proposed to be adequate for all disseminated tuberculosis syndromes, whether drug-resistant or -susceptible.
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Affiliation(s)
- Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Jotam Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Eric Nuermberger
- Center for Tuberculosis Research, Department of Medicine Department of International Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas Department of Medicine, University of Cape Town, Observatory, South Africa
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Deshpande D, Srivastava S, Nuermberger E, Pasipanodya JG, Swaminathan S, Gumbo T. Concentration-Dependent Synergy and Antagonism of Linezolid and Moxifloxacin in the Treatment of Childhood Tuberculosis: The Dynamic Duo. Clin Infect Dis 2017; 63:S88-S94. [PMID: 27742639 PMCID: PMC5064154 DOI: 10.1093/cid/ciw473] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Background. No treatment regimens have been specifically designed for children, in whom tuberculosis is predominantly intracellular. Given their activity as monotherapy and their ability to penetrate many diseased anatomic sites that characterize disseminated tuberculosis, linezolid and moxifloxacin could be combined to form a regimen for this need. Methods. We examined microbial kill of intracellular Mycobacterium tuberculosis (Mtb) by the combination of linezolid and moxifloxacin multiple exposures in a 7-by-7 mathematical matrix. We then used the hollow fiber system (HFS) model of intracellular tuberculosis to identify optimal dose schedules and exposures of moxifloxacin and linezolid in combination. We mimicked pediatric half-lives and concentrations achieved by each drug. We sampled the peripheral compartment on days 0, 7, 14, 21, and 28 for Mtb quantification, and compared the slope of microbial kill of Mtb by these regimens to the standard regimen of isoniazid, rifampin, and pyrazinamide, based on exponential decline regression. Results. The full exposure-response surface identified linezolid-moxifloxacin zones of synergy, antagonism, and additivity. A regimen based on each of these zones was then used in the HFS model, with observed half-lives of 4.08 ± 0.66 for linezolid and 3.80 ± 1.34 hours for moxifloxacin. The kill rate constant was 0.060 ± 0.012 per day with the moxifloxacin-linezolid regimen in the additivity zone vs 0.083 ± 0.011 per day with standard therapy, translating to a bacterial burden half-life of 11.52 days vs 8.53 days, respectively. Conclusions. We identified doses and dose schedules of a linezolid and moxifloxacin backbone regimen that could be highly efficacious in disseminated tuberculosis in children.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Eric Nuermberger
- Center for Tuberculosis Research, Department of Medicine Department of International Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | | | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas Department of Medicine, University of Cape Town, Observatory, South Africa
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Deshpande D, Srivastava S, Pasipanodya JG, Bush SJ, Nuermberger E, Swaminathan S, Gumbo T. Linezolid for Infants and Toddlers With Disseminated Tuberculosis: First Steps. Clin Infect Dis 2017; 63:S80-S87. [PMID: 27742638 PMCID: PMC5064157 DOI: 10.1093/cid/ciw482] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Infants and toddlers often present with disseminated and lymph node tuberculosis, in which Mycobacterium tuberculosis (Mtb) is predominantly intracellular. Linezolid, used to treat tuberculosis in adults, has not been formally studied in infants. Infants clear linezolid 5 times faster than adults and achieve lower 0- to 24-hour area under the concentration-time curves (AUC0-24). METHODS To mimic intracellular disease, we infected human-derived THP-1 macrophages with Mtb and inoculated hollow fiber systems. We performed dose-effect and dose-scheduling studies in which we recapitulated the linezolid half-life of 3 hours encountered in infants. Repetitive sampling for linezolid pharmacokinetics, Mtb intracellular burden, viable monocyte count, and RNA sequencing reads were performed up to 28 days. RESULTS The linezolid extracellular half-life was 2.64 ± 0.38 hours, whereas intracellular half-life was 8.93 ± 1.30 hours (r2 = 0.89). Linezolid efficacy was linked to the AUC0-24 to minimum inhibitory concentration (MIC) ratio (r2 = 0.98). The exposure associated with maximal Mtb kill was an AUC0-24/MIC of 23.37 ± 1.16. We identified a 414-gene transcript on exposure to toxic linezolid doses. The largest number of genes mapped to ribosomal proteins, a signature hitherto not associated with linezolid toxicity. The second-largest number of differentially expressed genes mapped to mitochondrial enzyme inhibition. Linezolid AUC0-24 best explained the mitochondrial gene inhibition, with 50% inhibition at 94 mg × hour/L (highest r2 = 0.98). CONCLUSIONS We identified the linezolid AUC0-24/MIC target for optimal efficacy against pediatric intracellular tuberculosis, and an AUC0-24 threshold associated with mitochondrial inhibition. These constitute a therapeutic window to be targeted for optimal linezolid doses in children with tuberculosis.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Stephen J Bush
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Eric Nuermberger
- Center for Tuberculosis Research, Department of Medicine Department of International Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas Department of Medicine, University of Cape Town, Observatory, South Africa
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Deshpande D, Srivastava S, Chapagain ML, Lee PS, Cirrincione KN, Pasipanodya JG, Gumbo T. The discovery of ceftazidime/avibactam as an anti-Mycobacterium avium agent. J Antimicrob Chemother 2017; 72:i36-i42. [PMID: 28922808 DOI: 10.1093/jac/dkx306] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
OBJECTIVES To determine if ceftaroline and ceftazidime combined with avibactam are efficacious against pulmonary Mycobacterium avium complex (MAC) disease. METHODS First, we performed a concentration-effect study of ceftaroline and ceftaroline/avibactam against extracellular MAC in test tubes. Given the difficulty of obtaining avibactam at the time of experimentation, we used a single concentration of commercial ceftazidime/avibactam, and two sets of non-treated controls, one with ceftazidime/avibactam and the other without. After finding antimicrobial activity with the ceftazidime/avibactam 'control', we performed ceftazidime/avibactam dose-effect studies in test tubes against extracellular MAC and in 24-well plates against intracellular MAC. We then performed a ceftazidime/avibactam exposure-effect and dose-fractionation studies in the hollow-fibre system model of intracellular pulmonary MAC (HFS-MAC). In each experiment, we repetitively sampled each HFS-MAC at specified times to validate ceftazidime/avibactam pharmacokinetics and to quantify bacterial burden. RESULTS Ceftaroline killed extracellular MAC with maximal microbial kill (Emax) of 4.87 ± 0.26 log10 cfu/mL. However, the ceftazidime/avibactam 'control' also killed MAC compared with the non-treated control. Ceftazidime/avibactam Emax was 3.8 log10 cfu/mL against extracellular bacilli and 3.6 log10 cfu/mL against intracellular MAC. In the HFS-MAC, ceftazidime/avibactam achieved a half-life of 2.5-3.3 h and killed MAC 0.61-2.40 log10 cfu/mL below the starting bacterial burden. The ceftazidime/avibactam efficacy was linked to the proportion of the dosing interval for which the concentration persists above the MIC (fT>MIC), with optimal efficacy at free-drug fT>MIC of 52% (r2 = 0.95). CONCLUSIONS Ceftazidime/avibactam effectively kills MAC at exposures easily achieved in the lung by clinical doses. Efficacy was higher than with clinically achievable doses of azithromycin and ethambutol.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Moti L Chapagain
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Pooi S Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Kayle N Cirrincione
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA
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Deshpande D, Srivastava S, Chapagain M, Magombedze G, Martin KR, Cirrincione KN, Lee PS, Koeuth T, Dheda K, Gumbo T. Ceftazidime-avibactam has potent sterilizing activity against highly drug-resistant tuberculosis. Sci Adv 2017; 3:e1701102. [PMID: 28875168 PMCID: PMC5576880 DOI: 10.1126/sciadv.1701102] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 08/03/2017] [Indexed: 06/07/2023]
Abstract
There are currently many patients with multidrug-resistant and extensively drug-resistant tuberculosis. Ongoing transmission of the highly drug-resistant strains and high mortality despite treatment remain problematic. The current strategy of drug discovery and development takes up to a decade to bring a new drug to clinical use. We embarked on a strategy to screen all antibiotics in current use and examined them for use in tuberculosis. We found that ceftazidime-avibactam, which is already used in the clinic for multidrug-resistant Gram-negative bacillary infections, markedly killed rapidly growing, intracellular, and semidormant Mycobacterium tuberculosis in the hollow fiber system model. Moreover, multidrug-resistant and extensively drug-resistant clinical isolates demonstrated good ceftazidime-avibactam susceptibility profiles and were inhibited by clinically achievable concentrations. Resistance arose because of mutations in the transpeptidase domain of the penicillin-binding protein PonA1, suggesting that the drug kills M. tuberculosis bacilli via interference with cell wall remodeling. We identified concentrations (exposure targets) for optimal effect in tuberculosis, which we used with susceptibility results in computer-aided clinical trial simulations to identify doses for immediate clinical use as salvage therapy for adults and young children. Moreover, this work provides a roadmap for efficient and timely evaluation of antibiotics and optimization of clinically relevant dosing regimens.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX 75204, USA
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX 75204, USA
| | - Moti Chapagain
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX 75204, USA
| | - Gesham Magombedze
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX 75204, USA
| | - Katherine R. Martin
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX 75204, USA
| | - Kayle N. Cirrincione
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX 75204, USA
| | - Pooi S. Lee
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX 75204, USA
| | - Thearith Koeuth
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX 75204, USA
| | - Keertan Dheda
- Lung Infection and Immunity Unit, Division of Pulmonology and University of Cape Town (UCT) Lung Institute, Department of Medicine, UCT, Observatory, 7925, Cape Town, South Africa
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX 75204, USA
- Lung Infection and Immunity Unit, Division of Pulmonology and University of Cape Town (UCT) Lung Institute, Department of Medicine, UCT, Observatory, 7925, Cape Town, South Africa
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Deshpande D, Srivastava S, Nuermberger E, Pasipanodya JG, Swaminathan S, Gumbo T. A Faropenem, Linezolid, and Moxifloxacin Regimen for Both Drug-Susceptible and Multidrug-Resistant Tuberculosis in Children: FLAME Path on the Milky Way. Clin Infect Dis 2016; 63:S95-S101. [PMID: 27742640 PMCID: PMC5064155 DOI: 10.1093/cid/ciw474] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND The regimen of linezolid and moxifloxacin was found to be efficacious in the hollow fiber system model of pediatric intracellular tuberculosis. However, its kill rate was slower than the standard 3-drug regimen of isoniazid, rifampin, and pyrazinamide. We wanted to examine the effect of adding a third oral agent, faropenem, to this dual combination. METHODS We performed a series of studies in the hollow fiber system model of intracellular Mycobacterium tuberculosis, by mimicking pediatric pharmacokinetics of each antibiotic. First, we varied the percentage of time that faropenem persisted above minimum inhibitory concentration (TMIC) on the moxifloxacin-linezolid regimen. After choosing the best faropenem exposure, we performed experiments in which we varied the moxifloxacin and linezolid doses in the triple regimen. Finally, we performed longer-duration therapy validation experiments. Bacterial burden was quantified using both colony-forming units per milliliter (CFU/mL) and time to positivity (TTP). Kill slopes were modeled using exponential regression. RESULTS TTP was a more sensitive measure of bacterial burden than CFU/mL. A faropenem TMIC > 62% was associated with steepest microbial kill slope. Regimens of standard linezolid and moxifloxacin plus faropenem TMIC > 60%, as well as higher-dose moxifloxacin, achieved slopes equivalent to those of the standard regimen based by both TTP and CFU/mL over 28 days of treatment. CONCLUSIONS We have developed an oral faropenem-linezolid-moxifloxacin (FLAME) regimen that is free of first-line drugs. The regimen could be effective against both multidrug-resistant and drug-susceptible tuberculosis in children.
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Affiliation(s)
- Devyani Deshpande
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | - Eric Nuermberger
- Center for Tuberculosis Research, Department of Medicine Department of International Health, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Jotam G Pasipanodya
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas
| | | | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, Texas Department of Medicine, University of Cape Town, Observatory, South Africa
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Deshpande D, Hill KE, Mealey KL, Chambers JP, Gieseg MA. The Effect of the Canine ABCB1-1Δ Mutation on Sedation after Intravenous Administration of Acepromazine. J Vet Intern Med 2016; 30:636-41. [PMID: 26822006 PMCID: PMC4913601 DOI: 10.1111/jvim.13827] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 10/14/2015] [Accepted: 12/16/2015] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Dog breeds with the ABCB1-1Δ mutation have substantially truncated nonfunctional P-glycoprotein. Dogs homozygous for this mutation (mut/mut) are susceptible to the toxic adverse effects of ivermectin, loperamide, and vincristine. Anecdotal reports suggested ABCB1 mut/mut dogs showed increased depth and duration of acepromazine sedation. HYPOTHESIS/OBJECTIVES That ABCB1 mut/mut dogs have increased depth and duration of sedation after acepromazine IV compared to normal dogs (nor/nor). ANIMALS Twenty-nine rough-coated collies were divided into 3 groups of dogs based on their ABCB1 genotype: 10 mut/mut, 10 mut/nor, and 9 nor/nor. METHODS Dogs were given 0.04 mg/kg of acepromazine IV. Level of sedation, heart rate, respiratory rate, and blood pressure were recorded for 6 hours after acepromazine administration. Area under the curves (AUCs) of the normalized sedation score results were calculated and compared. RESULTS The median sedation scores for ABCB1 mut/mut dogs were higher than nor/nor dogs at all time points and were higher in mut/nor dogs for the first 2 hours. These differences were not found to be significant for any individual time point (P > .05). The median sedation score AUC for mut/mut dogs was significantly higher than nor/nor dogs (P = .028), but the AUC for mut/nor dogs was not (P = .45). There were no significant differences between groups for heart rate, respiratory rate, and blood pressure (P > .05). CONCLUSIONS AND CLINICAL IMPORTANCE In ABCB1 mut/mut dogs acepromazine dose rates should be reduced and careful monitoring performed during sedation.
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Affiliation(s)
- D Deshpande
- Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand
| | - K E Hill
- Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand
| | - K L Mealey
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA
| | - J P Chambers
- Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand
| | - M A Gieseg
- Veterinary Health Research, Waikato Innovation Park, Hamilton, New Zealand
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Deshpande D, Fleming T, Gans R, Nawroth P. Decrease in endogenous opioids in streptozotocin induced diabetes mellitus correlates with heat hypersensitivity. DIABETOL STOFFWECHS 2015. [DOI: 10.1055/s-0035-1549578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Hidmark A, Fleming T, Deshpande D, Vittas S, Nawroth PP. STZ treatment causes depletion of immune cells in sciatic nerve and dorsal root ganglion in mice. DIABETOL STOFFWECHS 2015. [DOI: 10.1055/s-0035-1549571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Hidmark A, Fleming T, Vittas S, Mendler M, Deshpande D, Groener JB, Müller BP, Reeh PW, Sauer SK, Pham M, Muckenthaler MU, Bendszus M, Nawroth PP. A new paradigm to understand and treat diabetic neuropathy. Exp Clin Endocrinol Diabetes 2014; 122:201-7. [PMID: 24623503 DOI: 10.1055/s-0034-1367023] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The clinical symptoms of diabetic neuropathy (DN) manifest in a time dependent manner as a positive symptoms (i. e. pain, hypersensitivity, tingling, cramps, cold feet etc.) during its early stages and by a loss of function (i. e. loss of sensory perception, delayed wound healing etc.) predominating in the later stages. Elevated blood glucose alone cannot explain the development and progression of DN and the lowering of blood glucose is insufficient in preventing and/or reversing neuropathy in patients with type 2 diabetes. Recently it has been shown that the endogenous reactive metabolite methylglyoxal (MG) can contribute to the gain of function via post-translational modification in DN of neuronal ion channels involved in chemosensing and action potential generation in nociceptive nerve endings. Dicarbonyls, such as MG, that are elevated in diabetic patients, modify DNA as well as extra- and intracellular proteins, leading to the formation of advanced glycation endproducts (AGEs). Increased formation of AGEs leads to increased cellular stress, dysfunction and ultimately cell death. The interaction of AGE-modified proteins through cell surface receptors, such as RAGE, can lead to increased cellular activation and sustained inflammatory responses, which are the molecular hallmarks of the later, degenerative, stages of DN. The direct and indirect effects of dicarbonyls on nerves or neuronal microvascular network provides a unifying mechanism for the development and progression of DN. Targeting the accumulation of MG and/or prevention of RAGE interactions may therefore provide new, more effective, therapeutic approaches for the treatment of DN.
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Affiliation(s)
- A Hidmark
- Department of Medicine I and Clinical Chemistry, University Hospital of Heidelberg, Heidelberg, Germany
| | - T Fleming
- Department of Medicine I and Clinical Chemistry, University Hospital of Heidelberg, Heidelberg, Germany
| | - S Vittas
- Department of Medicine I and Clinical Chemistry, University Hospital of Heidelberg, Heidelberg, Germany
| | - M Mendler
- Department of Medicine I and Clinical Chemistry, University Hospital of Heidelberg, Heidelberg, Germany
| | - D Deshpande
- Department of Medicine I and Clinical Chemistry, University Hospital of Heidelberg, Heidelberg, Germany
| | - J B Groener
- Department of Medicine I and Clinical Chemistry, University Hospital of Heidelberg, Heidelberg, Germany
| | - B P Müller
- Department of Surgery, University of Heidelberg, Heidelberg, Germany
| | - P W Reeh
- Institute of Physiology and Pathophysiology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - S K Sauer
- Institute of Physiology and Pathophysiology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - M Pham
- Department of Neuroradiology, University of Heidelberg, Heidelberg, Germany
| | - M U Muckenthaler
- Department of Pediatric Oncology, Hematology, Immunology and Pulmonology, University of Heidelberg, Heidelberg, Germany
| | - M Bendszus
- Department of Neuroradiology, University of Heidelberg, Heidelberg, Germany
| | - P P Nawroth
- Department of Medicine I and Clinical Chemistry, University Hospital of Heidelberg, Heidelberg, Germany
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Mahantshetty U, Yathiraj P, Nachankar A, Ghadi Y, Chaudhari S, Engineer R, Chopra S, Deshpande D, Shrivastava S. A Prospective Study to Generate CTV to ITV Margins Using Cone Beam Verification CT for Pelvic IMRT in Locally-Advanced Cervical Cancers. Int J Radiat Oncol Biol Phys 2013. [DOI: 10.1016/j.ijrobp.2013.06.1897] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Chaudhari S, Engineer R, Deshpande D, Shrivastava S. SU-E-T-460: Image Based Treatment Planning for Intraluminal Brachytherapy in Bile Duct Carcinoma. Med Phys 2013. [DOI: 10.1118/1.4814893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Mahantshetty U, Krishnatry R, Jamema S, Ghadi Y, Engineer R, Chopra S, Deshpande D, Shrivastava S. PO-0961: Evolution of mr image based brachytherapy in cervical cancers at Tata Memorial Hospital. Radiother Oncol 2013. [DOI: 10.1016/s0167-8140(15)33267-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Swamidas J, Mahantshetty U, Deshpande D, Shrivastava S. SU-E-T-424: Inter-Fraction Variation of High Dose Regions of OARS in MR Image Based Cervix Brachytherapy Using Rigid Registration. Med Phys 2012; 39:3802. [DOI: 10.1118/1.4735513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Adurkar P, Rathod S, Shah R, Jalali R, Deshpande D. SU-E-T-442: Assessing Vertex Beam with its Dosimetric Relevance for Intracranial Tumours: A Computational Exploration. Med Phys 2012; 39:3806. [DOI: 10.1118/1.4735531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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