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Piplani P, Kumar A, Kulshreshtha A, Vohra T, Piplani V. Recent Development of DNA Gyrase Inhibitors: An Update. Mini Rev Med Chem 2024; 24:1001-1030. [PMID: 37909434 DOI: 10.2174/0113895575264264230921080718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 08/15/2023] [Accepted: 08/16/2023] [Indexed: 11/03/2023]
Abstract
Antibiotic or antimicrobial resistance is an urgent global public health threat that occurs when bacterial or fungal infections do not respond to the drug regimen designed to treat these infections. As a result, these microbes are not evaded and continue to grow. Antibiotic resistance against natural and already-known antibiotics like Ciprofloxacin and Novobiocin can be overcome by developing an agent that can act in different ways. The success of agents like Zodiflodacin and Zenoxacin in clinical trials against DNA gyrase inhibitors that act on different sites of DNA gyrase has resulted in further exploration of this target. However, due to the emergence of bacterial resistance against these targets, there is a great need to design agents that can overcome this resistance and act with greater efficacy. This review provides information on the synthetic and natural DNA gyrase inhibitors that have been developed recently and their promising potential for combating antimicrobial resistance. The review also presents information on molecules that are in clinical trials and their current status. It also analysed the SAR studies and mechanisms of action of enlisted agents.
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Affiliation(s)
- Poonam Piplani
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, 160017, India
| | - Ajay Kumar
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, 160017, India
| | - Akanksha Kulshreshtha
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, 160017, India
| | - Tamanna Vohra
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh, 160017, India
| | - Vritti Piplani
- Bhojia Dental College and Hospital, Baddi, 173205, India
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2
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Pathak K, Hart S, Lande L. Nontuberculous Mycobacteria Lung Disease (NTM-LD): Current Recommendations on Diagnosis, Treatment, and Patient Management. Int J Gen Med 2022; 15:7619-7629. [PMID: 36213301 PMCID: PMC9534142 DOI: 10.2147/ijgm.s272690] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/05/2022] [Indexed: 11/23/2022] Open
Abstract
Nontuberculous mycobacteria (NTM) are a group of ubiquitous environmental bacteria that can be found in soil, dust, and water. Mycobacterium avium complex (MAC) is the most common pathogen and the one most associated with chronic pulmonary disease. In recent years, the prevalence of Mycobacterium avium complex-related pulmonary disease (MAC-PD) has increased and is an emerging public health concern. This is due to a combination of environmental and geographic factors, dynamic changes in organism virulence and antimicrobial susceptibility, and evolving host susceptibility. Given the dynamic nature of the disease, management of NTM pulmonary disease (NTM-PD) often includes a multimodal approach including antimicrobial therapy, airway clearance techniques, limiting environmental exposures, and reducing susceptibility to NTM through prevention of reflux and maintenance of body weight. This review will explore the most recent concepts in the diagnosis, treatment, and management of individuals with NTM pulmonary infection.
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Affiliation(s)
- Kriti Pathak
- Division of Pulmonary and Critical Care Medicine, Lankenau Medical Center, Wynnewood, PA, USA
| | - Stephanie Hart
- Division of Pulmonary and Critical Care Medicine, Lankenau Medical Center, Wynnewood, PA, USA
| | - Leah Lande
- Division of Pulmonary and Critical Care Medicine, Lankenau Medical Center, Wynnewood, PA, USA
- Lankenau Institute for Medical Research, Wynnewood, PA, USA
- Correspondence: Leah Lande, Tel +1 610-642-3796, Email
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3
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Patel H, Skok C, Maxwell D, Sheikh S. Importance of asking a social history: atypical pulmonary infections and occupational hazards. BMJ Case Rep 2022; 15:e246567. [PMID: 35039362 PMCID: PMC8768500 DOI: 10.1136/bcr-2021-246567] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2021] [Indexed: 11/03/2022] Open
Abstract
Non-tuberculous mycobacteria (NTM) are ubiquitous in the environment, but NTM infection is limited to individuals with risk factors. We present a case of a 62-year-old man who presented with a 1 year history of cough and shortness of breath. History was notable for significant tobacco use and work as a sandblaster without the use of personal protective equipment. His chest X-ray showed bilateral upper lobe cavitary lesions, which were redemonstrated on chest CT. A sputum Gram stain was positive for acid-fast bacilli, but his tuberculosis QuantiFERON was negative. He was started on empiric tuberculosis treatment. Sputum cultures ultimately returned for Mycobacterium avium intracellulare complex, and treatment was narrowed to azithromycin, rifampin and ethambutol. The case highlights risk factors for NTM infection, notably for this patient, occupational exposures that likely lead to the development of pneumoconiosis. Healthcare providers should ask about occupational history and counsel patients about protection from occupational hazards.
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Affiliation(s)
- Hiten Patel
- Family and Community Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Christopher Skok
- Family and Community Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Dana Maxwell
- Family and Community Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Selim Sheikh
- Family and Community Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
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Pennington KM, Vu A, Challener D, Rivera CG, Shweta FNU, Zeuli JD, Temesgen Z. Approach to the diagnosis and treatment of non-tuberculous mycobacterial disease. J Clin Tuberc Other Mycobact Dis 2021; 24:100244. [PMID: 34036184 PMCID: PMC8135042 DOI: 10.1016/j.jctube.2021.100244] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Non-tuberculous mycobacteria (NTM) is a collective name given to a group of more than 190 species of Mycobacterium. The clinical presentation for most NTM infections is non-specific, often resulting in delayed diagnosis. Further complicating matters is that NTM organisms can be difficult to isolate. Medications used to treat NTM infection can be difficult for patients to tolerate, and prolonged courses of anti-mycobacterial therapy are often required for adequate suppression or eradication. Herein, we review different NTM syndromes, appropriate diagnostic tests, and treatment regimens.
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Key Words
- ADR, adverse drug reactions
- AFB, acid fast bacilli
- AST, antimicrobial-susceptibility testing
- ATS, American Thoracic Society
- BCG, Bacille Calmette-Guerin
- CLSI, Clinical and Laboratory Standards Institute
- COPD, chronic obstructive pulmonary disease
- ECG, electrocardiogram
- EMB, ethambutol
- Erm, erythromycin ribosomal methylase
- FDA, Food and Drug Administration
- HIV, human immunodeficiency virus
- HRCT, high resolution computed tomography
- IDSA, Infectious Disease Society of America
- INF-γ, interferon- γ
- INH, isoniazid
- MAC, Mycobacterium avium complex
- MALDI-TOF, matrix-assisted laser desorption ionization time-of-flight mass spectrometry
- MGIT, mycobacteria growth indicator tube
- MIC, minimum inhibitory concentrations
- Mycobacterium abscessus
- Mycobacterium avium
- NTM, non-tuberculous mycobacteria
- Non-tuberculous mycobacteria
- PCR, polymerase chain reaction
- PFT, pulmonary function test
- TB, tuberculosis
- TDM, therapeutic drug monitoring
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Affiliation(s)
- Kelly M Pennington
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic Rochester, MN, USA
| | - Ann Vu
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Mayo Clinic Rochester, MN, USA
| | - Douglas Challener
- Division of Infectious Diseases, Department of Medicine, Mayo Clinic Rochester, MN, USA
| | | | - F N U Shweta
- Division of Infectious Diseases, Department of Medicine, Mayo Clinic Rochester, MN, USA
| | - John D Zeuli
- Department of Pharmacy, Mayo Clinic Rochester, MN, USA
| | - Zelalem Temesgen
- Division of Infectious Diseases, Department of Medicine, Mayo Clinic Rochester, MN, USA
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5
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Non tuberculous mycobacteria pulmonary disease: patients and clinicians working together to improve the evidence base for care. Int J Infect Dis 2021; 113 Suppl 1:S73-S77. [PMID: 33781905 DOI: 10.1016/j.ijid.2021.03.064] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 03/18/2021] [Accepted: 03/19/2021] [Indexed: 12/24/2022] Open
Abstract
Non-tuberculous mycobacterial pulmonary disease is on the rise globally. It is often missed, and causes significant morbidity and even mortality. Here, members of a clinical research network and a patient support group discuss some of the current key issues in NTM management. In addition to the need for research into epidemiology, immunology and treatment, we recommend greater use of patient and clinician networks to: (i) educate primary and secondary care clinicians to develop a high index of suspicion when investigating and treating at risk populations. (ii) promote a multidisciplinary team. (iii) promote shared patient-clinician decision making throughout care. (iv) incorporate use of patient self-report measures to assess progress and outcomes. (v) increase education of patients on their illness and its management. (vi) recruit patients into research projects and registries to improve the clinical evidence base. (vii) increase co-production of research with key stakeholders such as patients and their families, using expert patients and patient groups. (viii) understand more about the psychological, social and economic consequences of the disease.
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Crilly NP, Ayeh SK, Karakousis PC. The New Frontier of Host-Directed Therapies for Mycobacterium avium Complex. Front Immunol 2021; 11:623119. [PMID: 33552087 PMCID: PMC7862709 DOI: 10.3389/fimmu.2020.623119] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 12/14/2020] [Indexed: 01/03/2023] Open
Abstract
Mycobacterium avium complex (MAC) is an increasingly important cause of morbidity and mortality, and is responsible for pulmonary infection in patients with underlying lung disease and disseminated disease in patients with AIDS. MAC has evolved various virulence strategies to subvert immune responses and persist in the infected host. Current treatment for MAC is challenging, requiring a combination of multiple antibiotics given over a long time period (for at least 12 months after negative sputum culture conversion). Moreover, even after eradication of infection, many patients are left with residual lung dysfunction. In order to address similar challenges facing the management of patients with tuberculosis, recent attention has focused on the development of novel adjunctive, host-directed therapies (HDTs), with the goal of accelerating the clearance of mycobacteria by immune defenses and reducing or reversing mycobacterial-induced lung damage. In this review, we will summarize the evidence supporting specific adjunctive, HDTs for MAC, with a focus on the repurposing of existing immune-modulatory agents targeting a variety of different cellular pathways. We also highlight areas meriting further investigation.
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Affiliation(s)
- Nathan P Crilly
- Department of Molecular and Comparative Pathobiology, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Samuel K Ayeh
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Petros C Karakousis
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States.,Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
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Stokes SS, Vemula R, Pucci MJ. Advancement of GyrB Inhibitors for Treatment of Infections Caused by Mycobacterium tuberculosis and Non-tuberculous Mycobacteria. ACS Infect Dis 2020; 6:1323-1331. [PMID: 32183511 DOI: 10.1021/acsinfecdis.0c00025] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The prospect of ever increasing antibiotic resistance eroding currently available treatment options for bacterial infections underscores the need to continue to identify new antibiotics, preferably those that act on novel targets or with novel mechanisms of action. Bacterial gyrase B subunit (GyrB), an essential component of bacterial gyrase required for successful DNA replication, represents such a target. We describe recent examples of GyrB inhibitors and point out their potential utility for treatment of mycobacterial diseases caused by Mycobacterium tuberculosis (TB) and non-tuberculous mycobacteria (NTM). Current therapeutic options for these diseases are often suboptimal due to resistance to current standard of care antibiotics. A future GyrB inhibitor-based antibiotic could offer a new and effective addition to the armamentarium for treatment of mycobacterial diseases and possibly for infections caused by other bacterial pathogens. One GyrB inhibitor, SPR720, has recently completed a first-in-human clinical trial and is in clinical development for the treatment of NTM and TB infections.
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Affiliation(s)
- Suzanne S. Stokes
- Spero Therapeutics, 675 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Rajender Vemula
- Spero Therapeutics, 675 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Michael J. Pucci
- Spero Therapeutics, 675 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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Chen X, Zhang S, Bi F, Guo C, Feng L, Wang H, Yao H, Lin D. Crystal structure of the N domain of Lon protease from Mycobacterium avium complex. Protein Sci 2020; 28:1720-1726. [PMID: 31306520 DOI: 10.1002/pro.3687] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 07/05/2019] [Accepted: 07/09/2019] [Indexed: 12/14/2022]
Abstract
Lon protease is evolutionarily conserved in prokaryotes and eukaryotic organelles. The primary function of Lon is to selectively degrade abnormal and certain regulatory proteins to maintain the homeostasis in vivo. Lon mainly consists of three functional domains and the N-terminal domain is required for the substrate selection and recognition. However, the precise contribution of the N-terminal domain remains elusive. Here, we determined the crystal structure of the N-terminal 192-residue construct of Lon protease from Mycobacterium avium complex at 2.4 å resolution,and measured NMR-relaxation parameters of backbones. This structure consists of two subdomains, the β-strand rich N-terminal subdomain and the five-helix bundle of C-terminal subdomain, connected by a flexible linker,and is similar to the overall structure of the N domain of Escherichia coli Lon even though their sequence identity is only 26%. The obtained NMR-relaxation parameters reveal two stabilized loops involved in the structural packing of the compact N domain and a turn structure formation. The performed homology comparison suggests that structural and sequence variations in the N domain may be closely related to the substrate selectivity of Lon variants. Our results provide the structure and dynamics characterization of a new Lon N domain, and will help to define the precise contribution of the Lon N-terminal domain to the substrate recognition.
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Affiliation(s)
- Xiaoyan Chen
- College of Chemistry and Chemical Engineering, Fujian Provincial Key Laboratory of Chemical Biology, Xiamen University, Xiamen, China
| | - Shijun Zhang
- State Key Laboratory for Cellular Stress Biology, Department of Biomedical Sciences, School of Life Sciences, Xiamen University, Xiang'an, Xiamen, China
| | - Fangkai Bi
- College of Chemistry and Chemical Engineering, Fujian Provincial Key Laboratory of Chemical Biology, Xiamen University, Xiamen, China
| | - Chenyun Guo
- College of Chemistry and Chemical Engineering, Fujian Provincial Key Laboratory of Chemical Biology, Xiamen University, Xiamen, China
| | - Liubin Feng
- College of Chemistry and Chemical Engineering, Fujian Provincial Key Laboratory of Chemical Biology, Xiamen University, Xiamen, China
| | - Huilin Wang
- College of Chemistry and Chemical Engineering, Fujian Provincial Key Laboratory of Chemical Biology, Xiamen University, Xiamen, China
| | - Hongwei Yao
- College of Chemistry and Chemical Engineering, Fujian Provincial Key Laboratory of Chemical Biology, Xiamen University, Xiamen, China
| | - Donghai Lin
- College of Chemistry and Chemical Engineering, Fujian Provincial Key Laboratory of Chemical Biology, Xiamen University, Xiamen, China
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Park YE, Chong YP, Kim YJ, Kim OH, Kwon BS, Shim TS, Jo KW. Outcome of shorter treatment duration in non-cavitary nodular bronchiectatic Mycobacterium avium complex lung disease. J Thorac Dis 2020; 12:338-348. [PMID: 32274100 PMCID: PMC7138995 DOI: 10.21037/jtd.2020.01.39] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background The recommended treatment duration for non-cavitary nodular bronchiectatic (NC-NB) Mycobacterium avium complex (MAC) lung disease (LD) is at least 12 months after culture conversion, but evidence supporting this is limited. This study investigated whether treatment for less than 12 months after culture conversion is acceptable in terms of recurrence rate. Methods The study enrolled the patients diagnosed with NC-NB MAC LD between 2001 and 2014 at a tertiary referral center in South Korea who received the standard treatment for at least 9 months after culture conversion up to October 2018. The patients were divided into a shorter treatment group (9-11 months after culture conversion) and a standard treatment group (≥12 months). Results Of the 228 patients enrolled, 59 (25.9%) were treated for 9-11 months after culture conversion and 169 (74.1%) for ≥12 months. The mean treatment durations after culture conversion in the shorter and standard treatment groups were 11.1 and 13.8 months, respectively (P<0.001). During median follow-up durations after the completion of treatment of 56.5 and 55.9 months, respectively, the recurrence rates in the two groups were similar, at 39.0% (23/59) and 36.7% (62/169). There were also no significant differences between the groups in the 1-year and 3-year recurrence rates. Conclusions Post-conversion treatment shorter than the recommended duration may be adequate in terms of recurrence rate for patients with NC-NB MAC LD who receive the standard treatment for at least 9 months after culture conversion.
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Affiliation(s)
- Yea Eun Park
- Division of Pulmonology and Critical Care Medicine, Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Yong Pil Chong
- Department of Infectious Diseases, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Ye-Jee Kim
- Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, Seoul, South Korea
| | - Ock-Hwa Kim
- Division of Pulmonology and Critical Care Medicine, Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Byoung Soo Kwon
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, South Korea
| | - Tae Sun Shim
- Division of Pulmonology and Critical Care Medicine, Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Kyung-Wook Jo
- Division of Pulmonology and Critical Care Medicine, Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
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Vinnard C, Mezochow A, Oakland H, Klingsberg R, Hansen-Flaschen J, Hamilton K. Assessing Response to Therapy for Nontuberculous Mycobacterial Lung Disease: Quo Vadis? Front Microbiol 2018; 9:2813. [PMID: 30524407 PMCID: PMC6256187 DOI: 10.3389/fmicb.2018.02813] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 11/01/2018] [Indexed: 12/26/2022] Open
Abstract
Assessing progression of disease or response to treatment remains a major challenge in the clinical management of nontuberculous mycobacterial (NTM) infections of the lungs. Serial assessments of validated measures of treatment response address whether the current therapeutic approach is on track toward clinical cure, which remains a fundamental question for clinicians and patients during the course of NTM disease treatment. The 2015 NTM Research Consortium Workshop, which included a patient advisory panel, identified treatment response biomarkers as a priority area for investigation. Limited progress in addressing this challenge also hampers drug development efforts. The Biomarker Qualification Program at the FDA supports the use of a validated treatment response biomarker across multiple drug development programs. Current approaches in clinical practice include microbiologic and radiographic monitoring, along with symptomatic and quality-of-life assessments. Blood-based monitoring, including assessments of humoral and cell-mediated NTM-driven immune responses, remain under investigation. Alignment of data collection schemes in prospective multicenter studies, including the support of biosample repositories, will support identification of treatment response biomarkers under standard-of-care and investigational therapeutic strategies. In this review, we outline the role of treatment monitoring biomarkers in both clinical practice and drug development frameworks.
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Affiliation(s)
- Christopher Vinnard
- Public Health Research Institute, New Jersey Medical School, Newark, NJ, United States
| | - Alyssa Mezochow
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Hannah Oakland
- Department of Medicine, Tulane University School of Medicine, New Orleans, LA, United States
| | - Ross Klingsberg
- Department of Medicine, Tulane University School of Medicine, New Orleans, LA, United States
| | - John Hansen-Flaschen
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Keith Hamilton
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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De Groote MA, Jarvis TC, Wong C, Graham J, Hoang T, Young CL, Ribble W, Day J, Li W, Jackson M, Gonzalez-Juarrero M, Sun X, Ochsner UA. Optimization and Lead Selection of Benzothiazole Amide Analogs Toward a Novel Antimycobacterial Agent. Front Microbiol 2018; 9:2231. [PMID: 30294313 PMCID: PMC6158578 DOI: 10.3389/fmicb.2018.02231] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 08/31/2018] [Indexed: 12/14/2022] Open
Abstract
Mycobacteria remain an important problem worldwide, especially drug resistant human pathogens. Novel therapeutics are urgently needed to tackle both drug-resistant tuberculosis (TB) and difficult-to-treat infections with nontuberculous mycobacteria (NTM). Benzothiazole adamantyl amide had previously emerged as a high throughput screening hit against M. tuberculosis (Mtb) and was subsequently found to be active against NTM as well. For lead optimization, we applied an iterative process of design, synthesis and screening of several 100 analogs to improve antibacterial potency as well as physicochemical and pharmacological properties to ultimately achieve efficacy. Replacement of the adamantyl group with cyclohexyl derivatives, including bicyclic moieties, resulted in advanced lead compounds that showed excellent potency and a mycobacteria-specific spectrum of activity. MIC values ranged from 0.03 to 0.12 μg/mL against M. abscessus (Mabs) and other rapid- growing NTM, 1–2 μg/mL against M. avium complex (MAC), and 0.12–0.5 μg/mL against Mtb. No pre-existing resistance was found in a collection of n = 54 clinical isolates of rapid-growing NTM. Unlike many antibacterial agents commonly used to treat mycobacterial infections, benzothiazole amides demonstrated bactericidal effects against both Mtb and Mabs. Metabolic labeling provided evidence that the compounds affect the transfer of mycolic acids to their cell envelope acceptors in mycobacteria. Mapping of resistance mutations pointed to the trehalose monomycolate transporter (MmpL3) as the most likely target. In vivo efficacy and tolerability of a benzothiazole amide was demonstrated in a mouse model of chronic NTM lung infection with Mabs. Once daily dosing over 4 weeks by intrapulmonary microspray administration as 5% corn oil/saline emulsion achieved statistically significant CFU reductions compared to vehicle control and non-inferiority compared to azithromycin. The benzothiazole amides hold promise for development of a novel therapeutic agent with broad antimycobacterial activity, though further work is needed to develop drug formulations for direct intrapulmonary delivery via aerosol.
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Affiliation(s)
- Mary A De Groote
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States
| | | | | | | | | | | | | | - Joshua Day
- Crestone, Inc., Boulder, CO, United States
| | - Wei Li
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Mary Jackson
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Mercedes Gonzalez-Juarrero
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States
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