Selection of clinically relevant drug concentrations for in vitro studies of candidates drugs for cancer repurposing: a proposal

Drug repurposing of widely prescribed patent-off and cheap drugs may provide affordable drugs for cancer treatment. Nevertheless, many preclinical studies of cancer drug repurposing candidates use in vitro drug concentrations too high to have clinical relevance. Hence, preclinical studies must use clinically achievable drug concentrations. In this work, several FDA-approved cancer drugs are analyzed regarding the correlation between the drug inhibitory concentrations 50% (IC50) tested in cancer cell lines and their corresponding peak serum concentration (Cmax) and area under the curve (AUC) reported in clinical studies of these drugs. We found that for most targeted cancer drugs, the AUC and not the Cmax is closest to the IC50; therefore, we suggest that the initial testing of candidate drugs for repurposing could select the AUC pharmacokinetic parameter and not the Cmax as the translated drug concentration for in vitro testing. Nevertheless, this is a suggestion only as experimental evidence does not exist to prove this concept. Studies on this issue are required to advance in cancer drug repurposing.

Pharmacokinetics/pharmacodynamics of ivosidenib in advanced IDH1-mutant cholangiocarcinoma: findings from the phase III ClarIDHy study

PURPOSE

Report pharmacokinetic (PK)/pharmacodynamic (PD) findings from the phase III ClarIDHy study and any association between PK/PD parameters and treatment outcomes in this population.

METHODS

Patients with mutant isocitrate dehydrogenase 1 (mIDH1) advanced cholangiocarcinoma were randomized at a 2:1 ratio to receive ivosidenib or matched placebo. Crossover from placebo to ivosidenib was permitted at radiographic disease progression. Blood samples for PK/PD analyses, a secondary endpoint, were collected pre-dose and up to 4 h post-dose on day (D) 1 of cycles (C) 1 - 2, pre-dose and 2 h post-dose on D15 of C1 - 2, and pre-dose on D1 from C3 onwards. Plasma ivosidenib and D-2-hydroxyglutarate (2-HG) were measured using liquid chromatography-tandem mass spectrometry. All clinical responses were centrally reviewed previously.

RESULTS

PK/PD analysis was available for samples from 156 ivosidenib-treated patients. Ivosidenib was absorbed rapidly following single and multiple oral doses (time of maximum observed plasma concentration [Tmax] of 2.63 and 2.07 h, respectively). Ivosidenib exposure was higher at C2D1 than after a single dose, with low accumulation. In ivosidenib-treated patients, mean plasma 2-HG concentration was reduced from 1108 ng/mL at baseline to 97.7 ng/mL at C2D1, close to levels previously observed in healthy individuals. An average 2-HG inhibition of 75.0% was observed at steady state. No plasma 2-HG decreases were seen with placebo. Plasma 2-HG reductions were observed in ivosidenib-treated patients irrespective of best overall response (progressive disease, or partial response and stable disease).

CONCLUSION

Once-daily ivosidenib 500 mg has a favorable PK/PD profile, attesting the 2-HG reduction mechanism of action and, thus, positive outcomes in treated patients with advanced mIDH1 cholangiocarcinoma.

CLINICAL TRIAL REGISTRATION

NCT02989857 Registered February 20, 2017.

Engineering the protein corona: Strategies, effects, and future directions in nanoparticle therapeutics

Nanoparticles (NPs) serve as versatile delivery systems for anticancer, antibacterial, and antioxidant agents. The manipulation of protein-NP interactions within biological systems is crucial to the application of NPs in drug delivery and cancer nanotherapeutics. The protein corona (PC) that forms on the surface of NPs is the interface between biomacromolecules and NPs and significantly influences their pharmacokinetics and pharmacodynamics. Upon encountering proteins, NPs undergo surface alterations that facilitate their clearance from circulation by the mononuclear phagocytic system (MPS). PC behavior depends largely on the biological microenvironment and the physicochemical properties of the NPs. This review describes various strategies employed to engineer PC compositions on NP surfaces. The effects of NP characteristics such as size, shape, surface modification and protein precoating on PC performance were explored. In addition, this study addresses these challenges and guides the future directions of this evolving field.

The drug-specific properties of hypoxia-inducible factor-prolyl hydroxylase inhibitors in mice reveal a significant contribution of the kidney compared to the liver to erythropoietin induction

AIMS

Kidney disease often leads to anemia due to a defect in the renal production of the erythroid growth factor erythropoietin (EPO), which is produced under the positive regulation of hypoxia-inducible transcription factors (HIFs). Chemical compounds that inhibit HIF-prolyl hydroxylases (HIF-PHs), which suppress HIFs, have been developed to reactivate renal EPO production in renal anemia patients. Currently, multiple HIF-PH inhibitors, in addition to conventional recombinant EPO reagents, are used for renal anemia treatment. This study aimed to elucidate the therapeutic mechanisms and drug-specific properties of HIF-PH inhibitors.

METHODS AND KEY FINDINGS

Gene expression analyses and mass spectrometry revealed that HIF-PH inhibitors (daprodustat, enarodustat, molidustat, and vadadustat) alter Epo gene expression levels in the kidney and liver in a drug-specific manner, with different pharmacokinetics in the plasma and urine after oral administration to mice. The drug specificity revealed the dominant contribution of EPO induction in the kidneys rather than in the liver to plasma EPO levels after HIF-PH inhibitor administration. We also found that several HIF-PH inhibitors directly induce duodenal gene expression related to iron intake, while these drugs indirectly suppress hepatic hepcidin expression to mobilize stored iron for hemoglobin synthesis through induction of the EPO-erythroferrone axis.

SIGNIFICANCE

Renal EPO induction is the major target of HIF-PH inhibitors for their therapeutic effects on erythropoiesis. Additionally, the drug-specific properties of HIF-PH inhibitors in EPO induction and iron metabolism have been shown in mice, providing useful information for selecting the proper HIF-PH inhibitor for each renal anemia patient.

Pharmacological insights on novel oral selective estrogen receptor degraders in breast cancer

The therapeutic landscape of estrogen receptor (ER)-positive breast cancer includes endocrine treatments with aromatase inhibitors (AIs), selective estrogen receptor modulators (SERMs), and selective estrogen receptor degraders (SERDs). Fulvestrant is the first approved SERD with proven efficacy and good tolerability in clinical practice. However, drug resistance, low receptor affinity, and parental administration stimulated the search for new oral SERDs opening a new therapeutic era in ER + breast cancer. Elacestrant is an orally bioavailable SERD that has been recently approved by the FDA for postmenopausal women with ER+, human epidermal growth factor receptor 2-negative (HER2-), estrogen receptor 1 (ESR1)-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy. Other molecules of the same class currently tested in clinical trials are amcenestrant, giredestrant, camizestrant, and imlunestrant. The current review article offers a detailed pharmacological perspective of this emerging drug class, which may help with their possible future clinical applications.

Understanding and Quantifying Network Robustness to Stochastic Inputs

A variety of biomedical systems are modeled by networks of deterministic differential equations with stochastic inputs. In some cases, the network output is remarkably constant despite a randomly fluctuating input. In the context of biochemistry and cell biology, chemical reaction networks and multistage processes with this property are called robust. Similarly, the notion of a forgiving drug in pharmacology is a medication that maintains therapeutic effect despite lapses in patient adherence to the prescribed regimen. What makes a network robust to stochastic noise? This question is challenging due to the many network parameters (size, topology, rate constants) and many types of noisy inputs. In this paper, we propose a summary statistic to describe the robustness of a network of linear differential equations (i.e. a first-order mass-action system). This statistic is the variance of a certain random walk passage time on the network. This statistic can be quickly computed on a modern computer, even for complex networks with thousands of nodes. Furthermore, we use this statistic to prove theorems about how certain network motifs increase robustness. Importantly, our analysis provides intuition for why a network is or is not robust to noise. We illustrate our results on thousands of randomly generated networks with a variety of stochastic inputs.

Twice-Daily Dolutegravir Based Antiretroviral Therapy with One Month of Daily Rifapentine and Isoniazid (1HP) for TB Prevention

BACKGROUND

One month of daily rifapentine + isoniazid (1HP) is an effective, ultrashort option for TB prevention in people with HIV (PWH). However, rifapentine may decrease antiretroviral drug concentrations and increase the risk of virologic failure. ACTG A5372 evaluated the effect of 1HP on the pharmacokinetics of twice daily dolutegravir.

METHODS

A5372 was a multicenter, pharmacokinetic study in PWH (≥18 years) already on dolutegravir-containing antiretroviral therapy with HIV RNA < 50 copies/mL. Participants received daily rifapentine/isoniazid (600mg/300mg) for 28 days as part of 1HP. Dolutegravir was increased to 50mg twice daily during 1HP and intensive pharmacokinetic sampling was performed on day 0 (before 1HP) and on the final day of 1HP treatment.

RESULTS

Thirty-two participants (41% female; 66% Black/African; median (Q1, Q3) age 42 (34, 49) years) were included in the pharmacokinetic analysis. Thirty-one of 32 had HIV RNA levels <50 copies/mL at the end of 1HP dosing. One participant had an HIV RNA of 160 copies/mL at day 28, with HIV RNA <50 copies/mL upon repeat testing on day 42. The median (Q1, Q3) dolutegravir trough concentration was 1751 ng/mL (1195, 2542) on day 0 vs. 1987ng/mL (1331, 2278) on day 28 (day 28:day 0 GMR 1.05, [90% CI 0.93-1.2]; p = 0.43). No serious adverse events were reported.

CONCLUSION

Dolutegravir trough concentrations with 50mg twice daily dosing during 1HP treatment were greater than those with standard dose dolutegravir once daily without 1HP. These pharmacokinetic, virologic, and safety data provide support for twice daily dolutegravir use in combination with 1HP for TB prevention.

Pharmacokinetics and pharmacodynamics of cyclodextrin-based oral drug delivery formulations for disease therapy

Oral drug administration has become the most common and preferred mode of disease treatment due to its good medication adherence and convenience. For orally administered drugs, the safety, efficacy, and targeting ability requirements have grown as disease treatment research advances. It is difficult to obtain prominent efficacy of traditional drugs simply via oral administration. Numerous studies have demonstrated that cyclodextrins (CDs) can improve the clinical applications of certain orally administered drugs by enhancing their water solubility and masking undesirable odors. Additionally, deeper studies have discovered that CDs can influence disease treatment by altering the drug pharmacokinetics (PK) or pharmacodynamics (PD). This review highlights recent research progress on the PK and PD effects of CD-based oral drug delivery in disease therapy. Firstly, the review describes the characteristics of current drug delivery modes in oral administration. Besides, we minutely summarized the different CD-containing drugs, focusing on the impact of CD-based alterations in PK or PD of orally administered drugs in treating diseases. Finally, we deeply discussed current challenges and future opportunities with regard to PK and PD of CD-based oral drug delivery formulations.

Dose selection for aztreonam-avibactam, including adjustments for renal impairment, for Phase IIa and Phase III evaluation

PURPOSE

A series of iterative population pharmacokinetic (PK) modeling and probability of target attainment (PTA) analyses based on emerging data supported dose selection for aztreonam-avibactam, an investigational combination antibiotic for serious Gram-negative bacterial infections.

METHODS

Two iterations of PK models built from avibactam data in infected patients and aztreonam data in healthy subjects with "patient-like" assumptions were used in joint PTA analyses (primary target: aztreonam 60% fT > 8 mg/L, avibactam 50% fT > 2.5 mg/L) exploring patient variability, infusion durations, and adjustments for moderate (estimated creatinine clearance [CrCL] > 30 to ≤ 50 mL/min) and severe renal impairment (> 15 to ≤ 30 mL/min). Achievement of > 90% joint PTA and the impact of differential renal clearance were considerations in dose selection.

RESULTS

Iteration 1 simulations for Phase I/IIa dose selection/modification demonstrated that 3-h and continuous infusions provide comparable PTA; avibactam dose drives joint PTA within clinically relevant exposure targets; and loading doses support more rapid joint target attainment. An aztreonam/avibactam 500/137 mg 30-min loading dose and 1500/410 mg 3-h maintenance infusions q6h were selected for further evaluation. Iteration 2 simulations using expanded PK models supported an alteration to the regimen (500/167 mg loading; 1500/500 mg q6h maintenance 3-h infusions for CrCL > 50 mL/min) and selection of doses for renal impairment for Phase IIa/III clinical studies.

CONCLUSION

A loading dose plus 3-h maintenance infusions of aztreonam-avibactam in a 3:1 fixed ratio q6h optimizes joint PTA. These analyses supported dose selection for the aztreonam-avibactam Phase III clinical program.

CLINICAL TRIAL REGISTRATION

NCT01689207; NCT02655419; NCT03329092; NCT03580044.

Pharmacodynamic evaluation of the etonogestrel contraceptive implant initiated midcycle with and without ulipristal acetate: An exploratory study

OBJECTIVE

To estimate the incidence of ovulation suppression within five days of etonogestrel 68 mg implant insertion in the presence of a dominant follicle with and without same-day ulipristal acetate.

STUDY DESIGN

This single site non-masked, exploratory randomized trial recruited people age 18-35 years with regular menstrual cycles, no pregnancy risk, and confirmed ovulatory function. We initiated transvaginal ultrasound examinations on menstrual day 7-9 and randomized participants 1:1 to etonogestrel implant alone or with concomitant ulipristal acetate 30 mg oral when a dominant follicle reached ≥14 mm in diameter. We completed daily sonography and serum hormone levels for up to seven days or transitioned to labs alone if sonographic follicular rupture occurred. We defined ovulation as follicular rupture followed by progesterone >3 ng/mL. We calculated point estimates, risk ratios and 95% confidence intervals for ovulation for each group. Ovulation suppression of ≥44% in either group (the follicular rupture suppression rate with oral levonorgestrel emergency contraception), would prompt future method testing.

RESULTS

From October 2020 to October 2022, we enrolled 40 people and 39 completed primary outcome assessments: 20 with etonogestrel implant alone (mean follicular size at randomization: 15.2 mm ± 0.9 mm) and 19 with etonogestrel implant + ulipristal acetate (mean follicular size at randomization: 15.4 mm ± 1.2 mm, p = 0.6). Ovulation suppression occurred in 13 (65%) of etonogestrel implant-alone participants (Risk ratio 0.6 (95% CI: 0.3, 1.1), p = 0.08) and seven (37%) of implant + ulipristal acetate participants.

CONCLUSIONS

Ovulation suppression of the etonogestrel implant alone exceeds threshold testing for future research while the implant + ulipristal acetate does not.

IMPLICATIONS

Data are lacking on midcycle ovulation suppression for the etonogestrel implant with and without oral ulipristal acetate. In this exploratory study, ovulation suppression occurred in 65% of implant participants and 37% of implant + ulipristal acetate participants. Ovulation suppression of the implant alone exceeds threshold testing for future emergency contraception research.

Population pharmacokinetics and pharmacodynamics of efmarodocokin alfa (IL-22Fc)

Efmarodocokin alfa (IL-22Fc) is a fusion protein of human IL-22 linked to the crystallizable fragment (Fc) of human IgG4. It has been tested in multiple indications including inflammatory bowel disease (IBD). The purposes of the present analyses were to describe the population pharmacokinetics (PK) of efmarodocokin alfa and perform pharmacodynamic (PD) analysis on the longitudinal changes of the PD biomarker REG3A after efmarodocokin alfa treatment as well as identify covariates that affect efmarodocokin alfa PK and REG3A PD. The data used for this analysis included 182 subjects treated with efmarodocokin alfa in two clinical studies. The population PK and PD analyses were conducted sequentially. Efmarodocokin alfa concentration-time data were analyzed using a nonlinear mixed-effects modeling approach, and an indirect response model was adopted to describe the REG3A PD data with efmarodocokin alfa serum concentration linked to the increase in REG3A. The analysis software used were NONMEM and R. A 3-compartment model with linear elimination best described the PK of efmarodocokin alfa. The estimated population-typical value for clearance (CL) was 1.12 L/day, and volume of central compartment was 6.15 L. Efmarodocokin alfa CL increased with higher baseline body weight, C-reactive protein, and CL was 27.6% higher in IBD patients compared to healthy subjects. The indirect response PD model adequately described the longitudinal changes of REG3A after efmarodocokin alfa treatment. A popPK and PD model for efmarodocokin alfa and REG3A was developed and covariates affecting the PK and PD were identified.

Ageing-related considerations for medication used in supportive care in cancer

Both randomized controlled trials (RCTs) and retrospective studies have shown that a comprehensive geriatric assessment (CGA) prior to a patient commencing systemic anti-cancer therapy (SACT) results in improved quality of life outcomes and is associated with a decreased risk of grade 3-5 toxicity; however, data are lacking in relation to adverse drug events (ADE) associated with supportive care medications. Supportive care medications are prescribed as prophylactic agents in a SACT regimen, for management of treatment related toxicity and for symptoms caused by the disease itself. While necessary, the commencement of SACT and supportive medications may cause, or exacerbate, a significant drug burden in older patients, some of whom may have existing comorbidities. For many medications, older adults are underrepresented in pharmacokinetic and pharmacodynamic modelling studies. In this article we will review ageing-related changes in pharmacokinetics and pharmacodynamics, as well as how these changes may impact supportive care medications. Additional considerations for prescribing these medications in older adults with cancer, such as polypharmacy, potentially inappropriate medications, drug-drug interactions, and anticholinergic burden, as well as ageing-related considerations and recommendations for supportive care medications commonly used in older adults with cancer are also reviewed.

Sialic Acid Mediated Endothelial and Hepatic Uptake: A Mechanism based Mathematic Model Elucidating the Complex Pharmacokinetics and Pharmacodynamics of Efmarodocokin Alfa, a Variably Glycosylated Fusion Protein

Sialic acid (SA) is crucial for protecting glycoproteins from clearance. Efmarodocokin alfa (IL-22Fc), a fusion protein agonist that links IL-22 to the crystallizable fragment (Fc) of human IgG4, contains 8 N-glycosylation sites and exhibits heterogeneous and variable terminal sialylation biodistribution. This presents a unique challenge for Pharmacokinetic (PK) and Pharmacodynamic (PD) analysis and cross-species translation. In this study, we sought to understand how varying SA levels and heterogeneous distribution contribute to IL-22Fc's complex PKPD properties. We initially used homogenous drug material with varying SA levels to examine PKPD in mice. Population PKPD analysis based on mouse data revealed that SA was a critical covariate simultaneously accounting for the substantial between subject variability (BSV) in clearance (CL), distribution clearance (CLd), and volume of distribution (Vd). In addition to the well-established mechanism by which SA inhibits ASGPR activity, we hypothesized a novel mechanism by which decrease in SA increases the drug uptake by endothelial cells. This decrease in SA, leading to more endothelial uptake, was supported by the neonatal Fc receptor (FcRn) dependent cell-based transcytosis assay. The population analysis also suggested in vivo EC50 (IL-22Fc stimulating Reg3β) was independent on SA, while the in-vitro assay indicated a contradictory finding of SA-in vitro potency relationship. We created a mechanism based mathematical (MBM) PKPD model incorporating the decrease in SA mediated endothelial and hepatic uptake, and successfully characterized the SA influence on IL-22Fc PK, as well as the increased PK exposure being responsible for increased PD. Thereby, the MBM model supported that SA has no direct impact on EC50, aligning with the population PKPD analysis. Subsequently, using the MBM PKPD model, we employed 5 subpopulation simulations to reconstitute the heterogeneity of drug material. The simulation accurately predicted the PKPD of heterogeneously and variably sialylated drug in mouse, monkey and human. The successful prospective validation confirmed the MBM's ability to predict IL-22Fc PK across variable SA levels, homogenous to heterogeneous material, and across species (R2=0.964 for clearance prediction). Our model prediction suggests an average of 1 mol/mol SA increase leads to a 50% increase in drug exposure. This underlines the significance of controlling sialic acid levels during lot-to-lot manufacturing.

Cistanche deserticola improves ovariectomized-induced osteoporosis mainly by regulating lipid metabolism: Insights from serum metabolomics using UPLC/Q-TOF-MS

ETHNOPHARMACOLOGICAL RELEVANCE

Cistanche deserticola (C. deserticola) is an edible and traditional medicine widely used in China, which has been confirmed to be effective in the treatment of postmenopausal osteoporosis (PMOP). Despite its proven efficacy, the exact role of C. deserticola in bone metabolism and its underlying mechanism has remained unclear.

AIM OF THE STUDY

In this research, we employed an in vivo model utilizing ovariectomized (OVX) rats to characterize the anti-osteoporotic activity and metabolic mechanism of the ethanol extract of C. deserticola (CHE).

MATERIALS AND METHODS

Fifty female Sprague-Dawley (SD) rats were randomly divided into five groups including sham operation group, model group, 0.1 g/kg estradiol valerate (EV) group as the positive control, low (0.6 g/kg) and high (1.2 g/kg) dosage CHE groups. Biochemical parameter analyses and histopathological experiments were conducted to assess the pharmacodynamic effects. Metabolomic analysis was conducted on serum samples to examine the metabolic profiles, identify potential biomarkers, and elucidate the metabolic pathways associated with CHE in OVX rats.

RESULTS

CHE treatment demonstrated significant anti-osteoporosis activity by regulating serum biochemical markers of bone turnover, improving cancellous bone structure, and reversing the decrease in bone mineral density. Furthermore, the clinical equivalent dose group (CHL) achieved superior overall outcomes. The main interventions of CHE on OVX rats involved the modulation of several key pathways, including steroid hormone biosynthesis, arachidonic acid metabolism, tyrosine and tryptophan metabolism, biotin metabolism, regulation of TRP channels by inflammatory mediators, primary bile acid biosynthesis, regulation of lipolysis in adipocytes, and bile secretion. 23 potential efficacy-related biomarkers within the metabolic network were identified. Among them, long-chain unsaturated fatty acids (eg. DHA and docosapentaenoic acid), steroid hormones, amino acids and carbohydrates were strongly correlated with bone resorption and formation markers. Additionally, it was observed four pathways (nucleotide, carbon, amino acid, and lipid metabolism) were implicated in the effects of CHE.

CONCLUSION

This study demonstrates that CHE improves bone loss in PMOP mainly through regulating lipid metabolism pathways, which provides an evidence base for CHE treatment of PMOP.

Ototoxic and nephrotoxic drugs in neonatal intensive care units: results of a Spanish and Italian survey

Neonates face heightened susceptibility to drug toxicity, often exposed to off-label medications with dosages extrapolated from adult or pediatric studies. Premature infants in Neonatal Intensive Care Units (NICUs) are particularly at risk due to underdeveloped pharmacokinetics and exposure to multiple drugs. The study aimed to survey commonly used medications with a higher risk of ototoxicity and nephrotoxicity in Spanish and Italian neonatal units. A prospective cross-sectional study was conducted in Italian and Spanish neonatal units using a web-based survey with 43 questions. A modified Delphi method involved experts refining the survey through online consensus. Ethical approval was obtained, and responses were collected from January to July 2023. The survey covered various aspects, including drug-related ototoxic and nephrotoxic management, hearing screening, and therapeutic drug monitoring. Responses from 131 participants (35.9% from Spain and 64.1% from Italy) revealed awareness of drug toxicity risks. Varied practices were observed in hearing screening protocols, and a high prevalence of ototoxic and nephrotoxic drug use, including aminoglycosides (100%), vancomycin (70.2%), loop diuretics (63.4%), and ibuprofen (62.6%). Discrepancies existed in guideline availability and adherence, with differences between Italy and Spain in therapeutic drug monitoring practices.

CONCLUSIONS

The study underscores the need for clinical guidelines and uniform practices in managing ototoxic and nephrotoxic drugs in neonatal units. Awareness is high, but inconsistencies in practices indicate a necessity for standardization, including the implementation of therapeutic drug monitoring and the involvement of clinical pharmacologists. Addressing these issues is crucial for optimizing neonatal care in Southern Europe.

WHAT IS KNOWN

• Neonates in intensive care face a high risk of nephrotoxicity and ototoxicity from drugs like aminoglycosides, vancomycin, loop diuretics, and ibuprofen. • Therapeutic drug monitoring is key for managing these risks, optimizing dosing for efficacy and minimizing side effects.

WHAT IS NEW

• NICUs in Spain and Italy show high drug toxicity awareness but differ in ototoxic/nephrotoxic drug management. • Urgent need for standard guidelines and practices to address nephrotoxic risks from aminoglycosides, vancomycin, loop diuretics, and ibuprofen.

Synergistic mechanism of stir-baked curcumae radix with vinegar in dysmenorrhea rats based on UPLC-Q-TOF/MS metabolomics

Curcumae Radix (i.e. Huangsiyujin: HSYJ), a well-known traditional Chinese medicine (TCM), has been widely used in clinical practice for many years to treat depression and primary dysmenorrhea. Modern pharmacological researches have demonstrated its anti-inflammatory, antidepressant, and dysmenorrhea relief effects. According to the processing theory of TCM, it is believed that stir-baked HSYJ with vinegar may enhance the ability to disperse stagnant hepatoqi and alleviate pain. However, whether the vinegar concoction of HSYJ can enhance the therapeutic effect on the Qi stagnation due to liver depression (LDQS) type of dysmenorrhea and what its mechanism has not been well explained. Based on the processing drugs theory of "stir-baked with vinegar into liver", a metabolomic approach was used to investigate the therapeutic effect and mechanism of stir-baked HSYJ with vinegar to enhance the treatment of dysmenorrhea in rats. By establishing a rat model of dysmenorrhea of the "LDQS" type, observation of hemorheology, uterine pathological sections, COX-2 and OTR protein expression and other indicators; analysis of urinary metabolic changes in rats by UPLC-Q-TOF-MS technique, to compare the differential biomarkers and metabolic pathways in the treatment of dysmenorrhea due to "liver stagnation and qi stagnation" before and after stir-baked HSYJ with vinegar. Stir-baked HSYJ with vinegar significantly inhibited the writhing response of rats, improved hemorheology, repaired damaged diseased uterus and inhibited high expression of COX-2 and OTR proteins in uterus; 68 differential metabolites were screened from the urine of rats, compared with the raw HSYJ, the levels of 14 metabolites were significantly changed in stir-baked HSYJ with vinegar, involving the pathways of phenylalanine, tyrosine and tryptophan metabolism, cysteine and methionine metabolism, aspartate and glutamate metabolism. The potentiating effect of stir-baked HSYJ with vinegar may be related to the regulation of multiple amino acid metabolic pathways.

Pharmacokinetics and pharmacodynamics of antibacterial peptide NZX in Staphylococcus aureus mastitis mouse model

Staphylococcus aureus is associated with dairy mastitis, which causes serious economic losses to dairy farming industry. Antibacterial peptide NZX showed good antibacterial activity against S. aureus. This study aimed to evaluate pharmacokinetics and pharmacodynamics of NZX against S. aureus-induced mouse mastitis. NZX exhibited potent in vitro antibacterial activity against the test S. aureus strains (minimal inhibitory concentration (MIC): 0.23-0.46 μM), low mutant prevention concentration (MPC: 1.18-3.68 μM), and a long post antibiotic effect (PAE: 2.20-8.84 h), which was superior to those of lincomycin and ceftiofur. Antibacterial mechanisms showed that NZX could penetrate the cell membrane, resulting in obvious cell membrane perforation and morphological changes, and bind to intracellular DNA. Furthermore, NZX had a good stability in milk environment (retention rate: 85.36%, 24 h) than that in mammary homogenate (47.90%, 24 h). In mouse mastitis model, NZX (25-400 μg/gland) could significantly reduce the bacterial load of mammary tissue in a dose-dependent manner. In addition, NZX (100 μg/gland) could relieve the inflammatory symptoms of mammary tissue, and significantly decreased its pathological scores. The concentration-time curve of NZX (100 μg/gland) in the mammary tissue was plotted and the corresponding pharmacokinetic parameters were obtained by non-compartment model calculation. Those parameters of Tmax, T1/2, Cmax and AUC were 0.5 h, 35.11 h, 32.49 μg/g and 391 μg·h/g, respectively. Therefore, these results suggest that NZX could act as a promising candidate for treating dairy mastitis disease caused by S. aureus. KEY POINTS: • NZX could kill S. aureus by dual mechanism involved in membrane and DNA disruption • NZX could relieve S. aureus-induced mouse mastitis • Pharmacokinetic parameters of NZX in mouse mammary gland were obtained.

Synergistic effects and molecular mechanisms of DL-3-n-butylphthalide combined with dual antiplatelet therapy in acute ischemic stroke

DL-3-n-butylphthalide (NBP) is isolated from the seeds of Apium graveolens L., and has been recently used as a neuroprotective agent for acute ischemic stroke. The present study aimed to determine the efficacy and safety of the combined use of dual antiplatelet therapy (DAPT) and NBP for treating of acute ischemic stroke in rats and to explore the synergistic mechanism of this treatment strategy in rat middle cerebral artery occlusion models. The efficacy of DAPT combined with NBP was evaluated by determining neurological deficits, infarction status, and histological changes. Changes in body weight, blood glucose level, blood count, and serum biochemical parameters were detected to evaluate the safety. To explore the synergistic pharmacological mechanism, the mRNA expression and protein levels of key proteins in the pyroptosis-inflammatory pathway, and the pyroptosis ratio of microglias were examined. Compared with the administration of NBP or DAPT alone, combination of them significantly improved neurological deficits, reduced infarct area, and repaired tissue injury and inflammation after cerebral ischemia. No hepatorenal toxicity was observed. The mRNA expression and protein levels of key proteins in the pyroptosis-inflammation pathway, and the pyroptosis ratio of microglias were significantly downregulated in the combined administration group than in the monotherapy group. We demonstrated that the combined use of NBP and DAPT exhibits better efficacy and high safety and plays a synergistic role by inhibiting the pyroptosis-inflammation pathway in the brain tissues, particularly in microglial cells.

Development of a target concentration intervention to individualize paroxysmal nocturnal hemoglobinuria treatment with pegcetacoplan

Pegcetacoplan (Aspaveli®/Empaveli™) is a factor C3 inhibitor that is approved for the treatment of paroxysmal nocturnal hemoglobinuria. An individualized dosing strategy might be useful to improve patient-friendliness and cost-effectiveness of this very expensive drug. Therefore, the aim of this study was to develop an individualized treatment regimen for pegcetacoplan based on the pharmacokinetic-pharmacodynamic data of the manufacturer. We conducted a clinical trial simulation with the approved dosing regimen of 1080 mg twice-weekly and a target concentration intervention-based dosing regimen in patients with and without prior eculizumab use. For eculizumab-naïve patients, the target concentration intervention-based dosing regimen resulted in a comparable fraction of patients with LDH normalization (LDH < 226 U/L) and hemoglobulin normalization (> 12 g/dL) compared to the approved regimen (LDH 50.2% and 50.0% respectively and hemoglobulin 45.6% and 44.4%). A modest dose reduction of ~ 5% was possible with target concentration intervention-based dosing. An intensified dosing interval was necessary in 2.3% of the patients however an interval prolongation was possible in 28.2% of the patients. Similar results were obtained for patients prior treated with eculizumab. In this study we show the potential of an individualized dosing regimen of pegcetacoplan with can improve patient friendliness in approximately 30% of the patients and improve therapy in approximately 2% of the patients at slightly reduced costs.

Recommendations for the safe use of direct oral anticoagulants in patients with cirrhosis based on a systematic review of pharmacokinetic, pharmacodynamic and safety data

PURPOSE

The popularity of direct oral anticoagulants (DOACs) is increasing among patients with cirrhosis. Cirrhosis has a major impact on the pharmacokinetics of drugs, potentially increasing adverse events. Safe use of drugs in cirrhosis requires a diligent risk-benefit analysis. The aim of this study is to develop practice recommendations for safe use of DOACs in cirrhosis based on a systematic review of pharmacokinetic, pharmacodynamic and safety data.

METHODS

We conducted a systematic literature search to identify studies on pharmacokinetics, pharmacodynamics and safety of DOACs in cirrhosis. Data were collected and presented in summary tables by severity of cirrhosis using the Child-Turcotte-Pugh (CTP) classification. A multidisciplinary expert panel evaluated the results and classified the DOACs according to safety.

RESULTS

Fifty four studies were included. All DOACs were classified as 'no additional risks known' for CTP A. For CTP B, apixaban, dabigatran and edoxaban were classified as 'no additional risks known'. Apixaban and edoxaban showed fewer adverse events in patients with cirrhosis, while dabigatran may be less impacted by severity of cirrhosis based on its pharmacokinetic profile. Rivaroxaban was classified as 'unsafe' in CTP B and C based on significant pharmacokinetic alterations. Due to lack of data, apixaban, dabigatran and edoxaban were classified as 'unknown' for CTP C.

CONCLUSION

DOACs can be used in patients with CTP A cirrhosis, and apixaban, dabigatran and edoxaban can also be used in CTP B. It is recommended to avoid rivaroxaban in CTP B and C. There is insufficient evidence to support safe use of other DOACs in CTP C cirrhosis.

A Randomized, Open-Label Study Conducted to Evaluate the Bioequivalence of Pegfilgrastim-cbqv On-Body Injector Versus Prefilled Syringe in Healthy Male Participants

INTRODUCTION

To help prevent febrile neutropenia, pegfilgrastim-cbqv (UDENYCA®; Coherus BioSciences), a pegfilgrastim (NEULASTA®; Amgen) biosimilar, is administered 24-96 h after myelosuppressive chemotherapy. Delivery of pegfilgrastim-cbqv using an on-body injector (OBI) provides an alternative method of administration, affording options in drug delivery. This study aimed to establish pharmacokinetic (PK) and pharmacodynamic (PD) bioequivalence and assess the safety of pegfilgrastim-cbqv administered using an OBI compared with a prefilled syringe (PFS).

METHODS

In this open-label, two-period crossover study, healthy adult male participants (N = 189) were randomly assigned 1:1 to receive pegfilgrastim-cbqv 6 mg subcutaneously using an OBI (n = 92) or a PFS (n = 95) in period 1 and then an injection via the other method in period 2. Primary PK end points were area under the concentration-time curve from time 0 to infinity, area under the concentration-time curve from time 0 to the last quantifiable concentration, and maximum plasma concentration. Secondary PD end points, safety, immunogenicity, and tolerability were also assessed.

RESULTS

The 90% confidence intervals (CIs) of the geometric mean ratios for the PK and PD end points fell within the predetermined range (80-125%), indicating PK and PD bioequivalence between pegfilgrastim-cbqv OBI and pegfilgrastim-cbqv PFS. Treatment-emergent adverse events (TEAEs) occurred in 87.8% and 75.8% of participants in the OBI and PFS groups, respectively. Most TEAEs were musculoskeletal effects. The most common OBI-related TEAE was injection site erythema (31.7%), which was mild, transient, and self-limiting. The incidence of treatment-emergent antidrug antibodies (ADAs) was similar between the OBI and PFS. ADAs had no apparent impact on PK, PD, or safety. Neutralizing antibodies were not detected in any participant.

CONCLUSIONS

Results of the study showed PK and PD bioequivalence of pegfilgrastim-cbqv administered using OBI compared with PFS. OBI and PFS administration had similar safety, tolerability, and immunogenicity profiles. No unexpected safety signals were identified. Graphical Abstract available for this article.

Advanced Model-based Approach to Evaluate Human Plasma, Cerebrospinal Fluid, and Neuronal mTORC1 Activation Biomarkers After NV-5138 Administration in Healthy Volunteers

PURPOSE

NV-5138 ([S]-2-amino-5,5-difluoro-4,4-dimethylpentanoic acid) is an orally bioavailable, small-molecule activator of the mechanistic target of rapamycin complex 1 (mTORC1) pathway in development for treatment-resistant depression. The authors established a model to describe the relationship between plasma and cerebrospinal fluid (CSF) concentrations of NV-5138 and between CSF concentrations and potential biomarkers thought to be associated with mTORC1 activity (ie, orotic acid, N-acetylmethionine, and N-formylmethionine).

METHODS

Data were collected from a randomized, double-blind, placebo-controlled, tolerability, and pharmacokinetic (PK) parameter study of 5 ascending (400, 800, 1600, 2400, and 3000 mg), once-daily oral doses of NV-5138 in healthy subjects. NV-5138 plasma PK parameter samples were collected at 15 time points over 24 hours on days 1 and 7, and at pre dose on days 2-6 for all doses. NV-5138 CSF PK parameter and CSF biomarker samples were collected on days 1 and 7 at pre dose and 4, 8, and 12 hours post dose for all doses except 3000 mg. A model-based approach was used to develop and validate a model that describes the relationship between NV-5138 in CSF and biomarker concentrations.

FINDINGS

Twenty-four of the 42 enrolled subjects had simultaneous plasma and CSF measurements of NV-5138 and CSF biomarker concentrations and were included in the PK parameter and pharmacodynamic (PD) analyses. A 2-compartment plasma and CSF PK parameter, with indirect PD effects, model was developed and validated. NV-5138 plasma concentrations were positively correlated with those in CSF, although CSF concentrations lagged slightly behind those in plasma, as indicated by a counterclockwise hysteresis effect. Similarly, the relationship between the PD measures of mTORC1 activation and NV-5138 was also characterized by counterclockwise hysteresis, when the increase in CSF biomarker concentrations lagged behind those of NV-5138, consistent with a signaling intermediary/cascade, such as mTORC1. Maximal biomarker activation was achieved at NV-5138 CSF concentrations of approximately 3 µg/mL, which were associated with daily doses of 1600 mg NV-5138. The safety profile analysis (n = 42) found that most of the reported adverse events were mild in severity, with no severe, serious, unusual, or unexpected adverse events or any dissociative effects; 2 subjects (400-mg cohort) discontinued due to adverse events that were judged to be unrelated to study medication.

IMPLICATIONS

The model will be used for designing future efficacy and tolerability studies. Consecutive daily doses of NV-5138 were well tolerated in this healthy volunteer study.

Protective effect of Inonotus obliquus polysaccharide on mice infected with Neospora caninum

The study aimed to explore the protective effects of Inonotus obliquus polysaccharide (IOP) on Neospora caninum (N. caninum) infection. Our data showed that the survival rate of the mice was the highest and the survival time was the longest when the IOP was 2 mg/10 g. In agreement with these observations, IOP alleviated the pathological damage in the various organs and tissues of the mice. Compared with that in the Neosporidium infection model group, the content of N. caninum in the heart, liver, spleen, lung, kidney and brain, determined through HE staining, was significantly lower. In addition, IOP inhibited the levels of immunoglobulin G1 (IgG1) and immunoglobulin G2 (IgG2a) from the 21st to 42nd day of the administration group, whereas the levels of interleukin-12 (IL-12) and serum tumor necrosis factor alpha (TNF-α) were down-regulated at 7 d - 42 d. The production of CD4+ T lymphocytes was promoted, the number of CD8+ T lymphocytes were significantly lower and the CD4+/CD8+ ratio was significantly elevated. Furthermore, IOP effectively balanced the levels of hormones including gonadotropin-releasing hormone (GnRH), luteotropic hormone (LH) and testosterone (T) in male mice, and progesterone (PROG), estradiol (E2) and prolactin (PRL) in female mice. These findings demonstrate that IOP exerts protective effects against pathological damage caused by N. caninum infection in mice, and improve the immune function of the organism and regulate the secretion balance of sex hormones.

Cefepime pharmacokinetics in adult extracorporeal membrane oxygenation patients

BACKGROUND

The impact of extracorporeal membrane oxygenation (ECMO) on the pharmacokinetics/dynamics (PK/PD) of beta-lactam antibiotics have not been well studied in general, but cefepime specifically has the least amount of data. We aimed to investigate whether ECMO alters the PK of cefepime in adult intensive care unit (ICU) patients.

METHODS

This single-center, retrospective case-control study evaluated cefepime therapeutic drug monitoring (TDM) results from ECMO patients that were matched 1:1 with TDM results in non-ECMO patients for drug regimen and renal function. The primary outcome was the difference in PK/PD of cefepime in ECMO compared with non-ECMO ICU patients. Secondary outcomes included hospital length of stay, treatment failure, superinfection, bacterial resistance, and survival to discharge.

RESULTS

Eighty-two patients were included with 44 matched cefepime concentrations in each group. ECMO patients had higher free maximum concentrations (fCmax) (p = 0.003), lower free minimum concentration (fCmin)/1x minimum inhibitory concentration (MIC) ratios (p = 0.040), and lower attainment of free Cmin/4x MIC (p = 0.010). There were no differences between the groups for free Cmin, time above 1xMIC or 4x MIC, and pharmacokinetic parameters (ke, half-life, and Vd). Of those who survived to discharge, hospital length of stay was longer in the ECMO group (p < 0.001). Patients on ECMO were more likely to experience treatment failure (p = 0.036). The incidence of bacterial resistance, superinfection, or survival were similar among the groups.

CONCLUSION

These data suggest that more aggressive empiric dosing may be warranted in patients on ECMO. Therapeutic drug monitoring and future prospective studies would provide more evidence to guide decision making regarding dose adjustments.

In silico study of combination thrombolytic therapy with alteplase and mutant pro-urokinase for fibrinolysis in ischemic stroke

The synergistic advantage of combining tissue plasminogen activator (tPA) with pro-urokinase (proUK) for thrombolysis has been demonstrated in several in vitro experiments, and a single site proUK mutant (m-proUK) has been developed for better stability in plasma. Based on these studies, combination thrombolytic therapy with intravenous tPA and m-proUK has been suggested as a promising treatment for patients with ischemic stroke. This paper evaluates the efficacy and safety of the dual therapy by computational simulations of pharmacokinetics and pharmacodynamics coupled with a local fibrinolysis model. Seven dose regimens are simulated and compared with the standard intravenous tPA monotherapy. Our simulation results provide more insights into the complementary reaction mechanisms of tPA and m-proUK during clot lysis and demonstrate that the dual therapy can achieve a similar recanalization time (about 50 min) to tPA monotherapy, while keeping the circulating fibrinogen level within a normal range. Specifically, our results show that for all dual therapies with a 5 mg tPA bolus, the plasma concentration of fibrinogen remains stable at around 7.5 μM after a slow depletion over 50 min, whereas a rapid depletion of circulating fibrinogen (to 5 μM) is observed with the standard tPA therapy, indicating the potential advantage of dual therapy in reducing the risk of intracranial hemorrhage. Through simulations of varying dose combinations, it has been found that increasing tPA bolus can significantly affect fibrinogen level but only moderately improves recanalization time. Conversely, m-proUK doses and infusion duration exhibit a mild impact on fibrinogen level but significantly affect recanalization time. Therefore, future optimization of dose regimen should focus on limiting the tPA bolus while adjusting m-proUK dosage and infusion rate. Such adjustments could potentially maximize the therapeutic advantages of this combination therapy for ischemic stroke treatment.

A first-in-human phase I study of TAS-117, an allosteric AKT inhibitor, in patients with advanced solid tumors

PURPOSE

TAS-117 is a highly potent and selective, oral, allosteric pan-AKT inhibitor under development for advanced/metastatic solid tumors. The safety, clinical pharmacology, pharmacogenomics and efficacy were investigated.

METHODS

This phase I, open-label, non-randomized, dose-escalating, first-in-human study enrolled patients with advanced/metastatic solid tumors and comprised three phases (dose escalation phase [DEP], regimen modification phase [RMP], and safety assessment phase [SAP]). The SAP dose and regimen were determined in the DEP and RMP. Once-daily and intermittent dosing (4 days on/3 days off, 21-day cycles) were investigated. The primary endpoints were dose-limiting toxicities (DLTs) in Cycle 1 of the DEP and RMP and incidences of adverse events (AEs) and adverse drug reactions (ADRs) in the SAP. Secondary endpoints included pharmacokinetics, pharmacodynamics, pharmacogenomics, and antitumor activity.

RESULTS

Of 66 enrolled patients, 65 received TAS-117 (DEP, n = 12; RMP, n = 10; SAP, n = 43). No DLTs were reported with 24-mg/day intermittent dosing, which was selected as a recommended dose in SAP. In the SAP, 98.5% of patients experienced both AEs and ADRs (grade ≥ 3, 67.7% and 60.0%, respectively). In the dose range tested (8 to 32 mg/day), TAS-117 pharmacokinetics were dose proportional, and pharmacodynamic analysis showed a reduction of phosphorylated PRAS40, a direct substrate of AKT. Four patients in the SAP had confirmed partial response.

CONCLUSION

Oral doses of TAS-117 once daily up to 16 mg/day and intermittent dosing of 24 mg/day were well tolerated. TAS-117 pharmacokinetics were dose proportional at the doses evaluated. Antitumor activity may occur through AKT inhibition.

TRIAL REGISTRATION

jRCT2080222728 (January 29, 2015).

Brivaracetam exposure-response predictions in pediatric patients from age 1 month: Extrapolation of levetiracetam adult-pediatric scaling to brivaracetam

BACKGROUND

An adult population pharmacokinetic/pharmacodynamic (PK/PD) model for the antiseizure medication (ASM) brivaracetam (BRV) was previously extended to children aged 4-16 years by using a pediatric BRV population PK model. Effects were scaled using information from a combined adult-pediatric PK/PD model of a related ASM, levetiracetam (LEV).

OBJECTIVE

To scale an existing adult population PK/PD model for BRV to children aged 1 month to < 4 years using information from a combined adult-pediatric PK/PD model for LEV, and to predict the effective dose of BRV in children aged 1 month to < 4 years using the adult BRV PK/PD model modified for the basal seizure rate in children.

MATERIAL AND METHODS

An existing adult population PK/PD model for BRV was scaled to children aged from 1 month to < 4 years using information from a combined adult-pediatric PK/PD model for LEV, an ASM binding to the same target protein as BRV. An existing adult-pediatric PK/PD model for LEV was extended using data from UCB study N01009 (NCT00175890) to include children as young as 1 month of age. The BRV population PK model was updated with data up to 180 days after first administration from BRV pediatric studies N01263 (NCT00422422) and N01266 (NCT01364597). PK and PD simulations for BRV were performed for a range of mg/kg doses to predict BRV effect in pediatric participants, and to provide dosing recommendations.

RESULTS

The extended adult-pediatric LEV PK/PD model was able to describe the adult and pediatric data using the same PD model parameters in adults and children and supported the extension of the adult BRV PK/PD model to pediatric patients aged 1 month to < 4 years. Simulations predicted exposures similar to adults receiving BRV 100 mg twice daily (b.i.d.), when using 3 mg/kg b.i.d. for weight < 10 kg, 2.5 mg/kg b.i.d. for weight ≥ 10 kg and < 20 kg, and 2 mg/kg b.i.d. for weight ≥ 20 kg in children aged 1 month to < 4 years. PK/PD simulations show that maximum BRV response is expected to occur with 2-3 mg/kg b.i.d. dosing of BRV in children aged 1 month to < 4 years, with an effective dose of 1 mg/kg b.i.d. for some participants.

CONCLUSION

Development of an adult-pediatric BRV PK/PD model allowed characterization of the exposure-response relationship of BRV in children aged 1 to < 4 years, providing a maximal dose allowance based on weight.

Effect of remifentanil on three effect-site concentrations of propofol and their relationship during electroencephalography at loss of response, at maximum alpha power, and at onset of burst suppression: a prospective randomized trial

PURPOSE

The effect-site concentration (Ce) at loss of response (Ce-LOR) to propofol closely correlates both with Ce as electroencephalographic alpha power becomes highest (Ce-alpha) and with Ce at onset of burst suppression (BS) (Ce-OBS), when no opioids are administered. Co-administration of opioids dose-dependently decreases Ce-LOR. We investigated the influence of remifentanil on the relationship between these three Ces.

METHODS

After receiving approval from our local ethical committee, with written informed consent, we enrolled 90 participants (ASA-PS I or II) who were scheduled for elective surgery. Participants were randomly assigned to three groups: constant remifentanil Ce 0 ng/ml (Remi_0); 1 ng/mL (Remi_1); and 2 ng/mL (Remi_2). We recorded both raw EEG and EEG-derived parameters on a computer. After reaching remifentanil equilibrium, we administered propofol using a target-controlled infusion pump such that propofol Ce increased to about 0.3 μg/mL/min. After determining Ce-LOR, we administered 0.6 mg/kg of rocuronium and started mask ventilation. The study protocol ended after observation of BS.

RESULTS

Three participants were excluded. Ce-LOR in each group (Remi_0, Remi_1, Remi_2) was 2.00 ± 0.58 μg/mL, 1.43 ± 0.49 μg/mL, and 1.37 ± 0.42 μg/mL. Ce-alpha was 2.91 ± 0.63 μg/mL, 2.30 ± 0.41 μg/mL, and 2.12 ± 0.39 μg/mL. Ce-OBS was 3.80 ± 0.69 μg/mL, 3.25 ± 0.68 μg/mL, and 2.90 ± 0.57 μg/mL. In three other instances, Ce was decreased by remifentanil. Generalized linear model analysis revealed that remifentanil had no influence on the relationship between the three Ces.

CONCLUSION

During propofol anesthesia, even low concentrations of remifentanil shifted concentration-related electroencephalographic changes.

Prolonged versus intermittent β-lactam infusion in sepsis: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The two latest studies on prolonged versus intermittent use of β-lactam antibiotics in patients with sepsis did not reach consistent conclusions, further contributing to the controversy surrounding the effectiveness of the prolonged β-lactam antibiotics infusion strategy. We conducted a systemic review and meta-analysis to evaluate the efficacy and safety of prolonged and intermittent β-lactam infusion in adult patients with sepsis.

METHODS

We systematically searched PubMed, EMBASE, and Cochrane Library databases for original randomized controlled trials comparing prolonged and intermittent β-lactam infusion in sepsis patients. A random-effects model was used to evaluate mortality, clinical success, microbiological success, and adverse events. We also conducted subgroup analyses to explore the impact of various factors on the mortality rates. Relative risk (RR) and corresponding 95% confidence intervals (CIs) were used to calculate the overall effect sizes for dichotomous outcomes. This meta-analysis was registered in PROSPERO (CRD42023463905).

RESULTS

We assessed 15 studies involving 2130 patients. In our comprehensive assessment, we found a significant reduction in all-cause mortality (RR, 0.83; 95% CI 0.72-0.97; P = 0.02) and a notable improvement in clinical success (RR, 1.16; 95% CI 1.03-1.31; P = 0.02) in the prolonged infusion group compared to the intermittent infusion group, whereas microbiological success did not yield statistically significant results (RR, 1.10; 95% CI 0.98-1.23; P = 0.11). No significant differences in adverse events were observed between the two groups (RR, 0.91; 95% CI 0.64-1.29; P = 0.60). Additionally, remarkable conclusions were drawn from subgroup analyses including studies with sample sizes exceeding 20 individuals per group (RR, 0.84; 95%CI 0.72-0.98; P = 0.03), research conducted post-2010 (RR, 0.84; 95%CI 0.72-0.98; P = 0.03), cases involving infections predominantly caused by Gram-negative bacteria (RR, 0.81; 95%CI 0.68-0.96; P = 0.02), as well as the administration of a loading dose (RR, 0.84; 95% CI 0.72-0.97; P = 0.02) and the use of penicillin (RR, 0.61; 95% CI 0.38-0.98; P = 0.04).

CONCLUSIONS

Compared to intermittent infusion, prolonged infusion of β-lactam antibiotics significantly decreases all-cause mortality among patients with sepsis and enhances clinical success without increasing adverse events.

Total alditols from Cistanche deserticola attenuate functional constipation by regulating bile acid metabolism

HEADINGS ETHNOPHARMACOLOGICAL RELEVANCE

Functional constipation (FC), characterized by chronic constipation, significantly impacts physiological function and induces psychological stress in patients. However, current clinical treatment options for FC are currently limited. Cistanche deserticola, a traditional Chinese medicine that promotes intestinal moisture and bowel relaxation, contains cistanche total alditol extract (CTAE) as its primary active extract. However, the production of CTAE, its overall efficacy, and potential mechanisms for treating FC have yet to been investigated.

AIM OF THE STUDY

This study aimed to reveal the overall efficacy and potential mechanism of action of CTAE in rats with FC using a combination of stable preparation, pharmacodynamics, non-targeted metabolomics, bile acid metabolomics, and western blotting.

MATERIALS AND METHODS

Fourteen batches of CTAE underwent quality testing. A rat model of FC was developed using diphenoxylate tablets. The comprehensive pharmacodynamic effects of CTAE on FC were evaluated using fecal characteristics (wet weight, dry weight, and water content), intestinal transmission (colonic EMG amplitude, colonic EMG frequency, propulsion length, and propulsion rate), serum and colon biochemical indicators, distribution of interstitial cells of Cajal (ICC), and pathological examination. Non-targeted metabolomics was performed to assess the changes in endogenous metabolite profiles induced by CTAE. Bile acid metabolomics and western blotting analyses were employed to validate the potential mechanisms of action of CTAE.

RESULTS

CTAE, with a total content of betaine, mannitol, D-fructose, glucose, and sucrose of (75.67 ± 3.73) %, significantly enhanced intestinal transit, regulated neurotransmitters, increased the expression of c-kit in ICC, and alleviated intestinal inflammation in rats with FC. Non-targeted metabolomics revealed that CTAE significantly alleviated FC-induced metabolic disorders, mainly the biosynthesis of primary bile acids. Targeted metabolomic analysis confirmed that CTAE regulated FC-induced bile acid disorders. Western-blotting results confirmed that CTAE increased the expression of CYP8B1, FGF15, TGR5, and FXR, thereby modulating bile acid synthesis and enterohepatic circulation.

CONCLUSION

CTAE demonstrates significant therapeutic effects on FC, primarily through the regulation of bile acid synthesis and enterohepatic circulation. These findings provide a promising foundation for the development and clinical application of novel CATE-based drugs.

Modeling population pharmacokinetics of morniflumate in healthy Korean men: extending pharmacometrics analysis to niflumic acid, its major active metabolite

This study aimed to quantify and explain inter-subject variability in morniflumate pharmacokinetics and identify effective covariates through population pharmacokinetics modeling. Models were constructed using bioequivalence pharmacokinetics results from healthy Korean males and individual physiological and biochemical parameters. Additionally, we incorporated previously reported pharmacokinetics results of niflumic acid, a major active metabolite of morniflumate, to extend the established population pharmacokinetics model and predict niflumic acid pharmacokinetics. Moreover, we used quantitative reports of leukotriene B4 (LTB4) synthesis inhibition in response to niflumic acid exposure to predict drug efficacy using Sigmoid Emax model. Population pharmacokinetics profiles of morniflumate were described using a multi-absorption (5-sequential) two-compartment model, and analysis of inter-individual variability suggested that volume of distribution in peripheral compartment was correlated with body mass index (BMI). Model simulation results showed that individuals with lower BMI had higher plasma concentrations of morniflumate and niflumic acid, resulting in increased and sustained inhibition of LTB4 synthesis. Under steady-state conditions, average plasma concentrations of morniflumate and niflumic acid were 2.66-2.68 times higher in group with a BMI of 17.36 kg/m2 compared to the group with a BMI of 28.41 kg/m2. Additionally, inhibition of LTB4 synthesis was 1.02 times higher in group with a BMI of 17.36 kg/m2 compared to group with a BMI of 28.41 kg/m2, and the fluctuation was significantly reduced from 6.06 to 0.01%. These findings suggest that the concentration of active metabolite in plasma following morniflumate exposure was lower in the obese group compared to the normal group, thus potentially reducing the drug's efficacy.

Challenges of pediatric pharmacotherapy: A narrative review of pharmacokinetics, pharmacodynamics, and pharmacogenetics

PURPOSE

Personalized pharmacotherapy, including for the pediatric population, provides optimal treatment and has emerged as a major trend owing to advanced drug therapeutics and diversified drug selection. However, it is essential to understand the growth and developmental characteristics of this population to provide appropriate drug therapy. In recent years, clinical pharmacogenetics has accumulated knowledge in pediatric pharmacotherapy, and guidelines from professional organizations, such as the Clinical Pharmacogenetics Implementation Consortium, can be consulted to determine the efficacy of specific drugs and the risk of adverse effects. However, the existence of a large knowledge gap hinders the use of these findings in clinical practice.

METHODS

We provide a narrative review of the knowledge gaps in pharmacokinetics (PK) and pharmacodynamics (PD) in the pediatric population, focusing on the differences from the perspective of growth and developmental characteristics. In addition, we explored PK/PD in relation to pediatric clinical pharmacogenetics.

RESULTS

The lack of direct and indirect biomarkers for more accurate assessment of the effects of drug administration limits the current knowledge of PD. In addition, incorporating pharmacogenetic insights as pivotal covariates is indispensable in this comprehensive synthesis for precision therapy; therefore, we have provided recommendations regarding the current status and challenges of personalized pediatric pharmacotherapy. The integration of clinical pharmacogenetics with the health care system and institution of educational programs for health care providers is necessary for its safe and effective implementation. A comprehensive understanding of the physiological and genetic complexities of the pediatric population will facilitate the development of effective and personalized pharmacotherapeutic strategies.

Expression, Purification, and Biological Evaluation of XTEN-GCSF in a Neutropenic Rat Model

Granulocyte colony-stimulating factor (GCSF) stimulates the proliferation of neutrophils but it has low serum half-life. Therefore, the present study was done to investigate the effect of XTENylation on biological activity, pharmacokinetics, and pharmacodynamics of GCSF in a neutropenic rat model. XTEN tag was genetically fused to the N-terminal region of GCSF-encoding gene fragment and subcloned into pET28a expression vector. The cytoplasmic expressed recombinant protein was characterized through intrinsic fluorescence spectroscopy (IFS), dynamic light scattering (DLS), and size exclusion chromatography (SEC). In vitro biological activity of the XTEN-GCSF protein was evaluated on NFS60 cell line. Hematopoietic properties and pharmacokinetics were also investigated in a neutropenic rat model. An approximately 140 kDa recombinant protein was detected on SDS-PAGE. Dynamic light scattering and size exclusion chromatography confirmed the increase in hydrodynamic diameter of GCSF molecule after XTENylation. GCSF derivatives showed efficacy in proliferation of NFS60 cell line among which the XTEN-GCSF represented the lowest EC50 value (100.6 pg/ml). Pharmacokinetic studies on neutropenic rats revealed that XTEN polymer could significantly increase protein serum half-life in comparison with the commercially available GCSF molecules. PEGylated and XTENylated GCSF proteins were more effective in stimulation of neutrophils compared to the GCSF molecule alone. XTENylation of GCSF represented promising results in in vitro and in vivo studies. This approach can be a potential alternative to PEGylation strategies for increasing serum half-life of protein.

Inhibition of Receptor-Interacting Protein Kinase 1 in Chronic Plaque Psoriasis: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Study

INTRODUCTION

Receptor-interacting protein kinase 1 (RIPK1), a key mediator of inflammation through necroptosis and proinflammatory cytokine production, may play a role in the pathogenesis of immune-mediated inflammatory diseases such as chronic plaque psoriasis. An experimental medicine study of RIPK1 inhibition with GSK2982772 immediate-release formulation at doses up to 60 mg three times daily in mild to moderate plaque psoriasis indicated that efficacy may be improved with higher trough concentrations of GSK2982772.

METHODS

This multicenter, randomized, double-blind, placebo-controlled, repeat-dose study (NCT04316585) assessed the efficacy, safety, pharmacokinetics, and pharmacodynamics of 960 mg GSK2982772 (once-daily modified-release formulation) in patients with moderate to severe plaque psoriasis. Twenty-nine patients were randomized 2:1 to GSK2982772 (N = 19) or placebo (N = 10) for 12 weeks.

RESULTS

GSK2982772 was well tolerated with trough concentrations greater than tenfold higher than the previous phase 1 study with immediate release. Despite near complete RIPK1 target engagement in blood and modest reduction in circulating inflammatory cytokines, the proportion of patients achieving 75% improvement from baseline in Psoriasis Area Severity Index score at week 12 was similar between GSK2982772 and placebo (posterior median 1.8% vs 4.9%, respectively), with an estimated median treatment difference of - 2.3%. This analysis incorporated historical placebo data through the use of an informative prior distribution on the placebo arm. Week 4 changes in skin biopsy gene expression suggested sufficient local drug exposure to elicit a pharmacodynamic response.

CONCLUSION

Administration of the RIPK1 inhibitor GSK2982772 to patients with moderate to severe plaque psoriasis did not translate into meaningful clinical improvements.

Pharmacogenomics of Preeclampsia therapies: Current evidence and future challenges for clinical implementation

Preeclampsia is a pregnancy-specific disorder, and it is a leading cause of maternal and perinatal morbidity and mortality. The application of pharmacogenetics to antihypertensive agents and dose selection in women with preeclampsia is still in its infancy. No current prescribing guidelines from the clinical pharmacogenetics implementation consortium (CPIC) exist for preeclampsia. Although more studies on pharmacogenomics are underway, there is some evidence for the pharmacogenomics of preeclampsia therapies, considering both the pharmacokinetic (PK) and pharmacodynamic (PD) properties of drugs used in preeclampsia. It has been revealed that the CYP2D6*10 variant is significantly higher in women with preeclampsia who are non-responsive to labetalol compared to those who are in the responsive group. Various genetic variants of PD targets, i.e., NOS3, MMP9, MMP2, TIMP1, TIMP3, VEGF, and NAMPT, have been investigated to assess the responsiveness of antihypertensive therapies in preeclampsia management, and they indicated that certain genetic variants of MMP9, TIMP1, and NAMPT are more frequently observed in those who are non-responsive to anti-hypertensive therapies compared to those who are responsive. Further, gene-gene interactions have revealed that NAMPT, TIMP1, and MMP2 genotypes are associated with an increased risk of preeclampsia, and they are more frequently observed in the non-responsive subgroup of women with preeclampsia. The current evidence is not rigorous enough for clinical implementation; however, an institutional or regional-based retrospective analysis of audited data may help close the knowledge gap during the transitional period from a traditional approach (a "one-size-fits-all" strategy) to the pharmacogenomics of preeclampsia therapies.

Mechanism of DaiTongXiao in the treatment of gouty arthritis through the NLRP3 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

DaiTongXiao (DTX) is a traditional Chinese Dai folk formulation utilized for gouty arthritis treatment, with substantial evidence supporting its anti-inflammatory properties. The NLRP3 inflammasome disorder is tightly linked to the development of many inflammatory diseases.

AIM OF THE STUDY

To elucidate the therapeutic efficacy of DTX in gouty arthritis and reveal its potential underlying mechanism.

MATERIALS AND METHODS

The primary active constituents in DTX were determined through ultraviolet spectrophotometry and gas chromatography. Rats underwent induction with monosodium urate (MSU), followed by treatment of J774A.1 cells with adenosine triphosphate (ATP) activation and lipopolysaccharide (LPS) induction and the subsequent culture in Dulbecco's modified Eagle's medium. The degree of foot joint swelling in rats was assessed, and ankle joints were evaluated through H&E staining. Enzyme-linked immunosorbent assay was performed to measure the levels of interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α in both serum and cells. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to determine the relative mRNA expression levels of NLRP3, ASC, Caspase-1, and NF-κB in J774A.1 macrophages. The expression of NLRP3, ASC, Caspase-1, and NF-κB was examined by western blotting.

RESULTS

DTX could alleviate MSU-induced joint swelling in rats, as evidenced by a reduction in joint inflammation. Moreover, DTX effectively enhanced the survival rate of J774A.1 cells following LPS induction and ATP activation. Furthermore, DTX significantly reduced IL-1β, IL-6, IL-8, and TNF-α levels in both cell culture medium and rat serum. RT-PCR results revealed that DTX notably downregulated the mRNA expression levels of NLRP3, ASC, Caspase-1, and NF-κB in J774A.1 cells. Additionally, DTX downregulated NLRP3, ASC, NF-κB, and Caspase-1 expression in the joint tissue.

CONCLUSIONS

DTX exerts a significant anti-gouty arthritis effect, with its mechanism being tightly linked to the NLRP3 inflammatory signaling pathway. This pathway may be modulated by inhibiting IL-1β differentiation and maturation by downregulating NLRP3, ASC, Caspase-1, and NF-κB protein expression. This, in turn, leads to a reduction in the release of IL-6, IL-8, and TNF-α, ultimately impeding gouty arthritis progression.

Safety, pharmacokinetics and pharmacodynamics of HWH486 capsules in healthy adults: A randomized, double-blind, placebo-controlled, phase I dose-escalation study

OBJECTIVES

HWH486 inhibits Bruton's tyrosine kinase and therefore shows promise as a treatment against rheumatoid arthritis and chronic spontaneous urticaria. This phase I trial assessed tolerability, safety, pharmacokinetics and pharmacodynamics of a single oral dose of HWH486 capsules in healthy adults.

METHODS

A single-center, randomized, double-blind, placebo-controlled, dose-escalation study from 10 to 800 mg was conducted in 96 healthy Chinese adults, of whom 80 received HWH486 and 16 received placebo.

RESULTS

A total of 96 subjects were enrolled, and all completed the study. In the HWH486 group, mean Tmax ranged from 1.03 to 2.00 h, and mean T1/2 ranged from 0.85 to 8.67 h across the dose range from 10 to 800 mg. Mean Cmax increased linearly with dose, while mean AUC0-t increased non-linearly. Occupancy of Bruton's tyrosine kinase peaked within 0.50-4.00 h after administration across the dose groups, and the delay until peak occupancy decreased with increasing dose. Twenty-five subjects (31.25 %) in the HWH486 group experienced 35 treatment-emergent adverse events, while four subjects (25.00 %) in the placebo group experienced eight such events.

CONCLUSIONS

HWH486 is well tolerated and safe in healthy adults, in whom it can strongly bind Bruton's tyrosine kinase. These findings justify clinical studies of HWH486 efficacy against autoimmune diseases.

A novel, small-volume subcutaneous furosemide formulation delivered by an abdominal patch infusor device in patients with heart failure: results of two phase I studies

AIMS

Subcutaneous (SC) furosemide has potential advantages over intravenous (IV) furosemide by enabling self-administration or administration by a lay caregiver, such as facilitating early discharge, preventing hospitalizations, and in palliative care. A high-concentration, pH-neutral furosemide formulation has been developed for SC administration via a small patch infusor pump. We aimed to compare the bioavailability, pharmacokinetic (PK), and pharmacodynamic (PD) profiles of a new SC furosemide formulation with conventional IV furosemide and describe the first use of a bespoke mini-pump to administer this formulation.

METHODS AND RESULTS

A novel pH-neutral formulation of SC furosemide containing 80 mg furosemide in ∼2.7 mL (infused over 5 h) was investigated. The first study was a PK/PD study of SC furosemide compared with 80 mg IV furosemide administered as a bolus in ambulatory patients with heart failure (HF). The primary outcome was absolute bioavailability of SC compared with IV furosemide. The second study investigated the same SC furosemide preparation delivered by a patch infusor in patients hospitalized with HF. Primary outcome measures were treatment-emergent adverse events, infusion site pain, device performance, and PK measurements.The absolute bioavailability of SC furosemide in comparison to IV furosemide was 112%, resulting in equivalent diuresis and natriuresis. When SC furosemide was administered via the patch pump, there were no treatment-emergent adverse events and 95% of participants reported no/minor discomfort at the infusion site.

CONCLUSION

The novel preparation of SC furosemide had similar bioavailability to IV furosemide. Administration via a patch pump was feasible and well tolerated.

Prospective study to characterize adalimumab exposure in pediatric patients with rheumatic diseases

BACKGROUND

In pediatric rheumatic diseases (PRD), adalimumab is dosed using fixed weight-based bands irrespective of methotrexate co-treatment, disease activity (DA) or other factors that might influence adalimumab pharmacokinetics (PK). In rheumatoid arthritis (RA) adalimumab exposure between 2-8 mg/L is associated with clinical response. PRD data on adalimumab is scarce. Therefore, this study aimed to analyze adalimumab PK and its variability in PRD treated with/without methotrexate.

METHODS

A two-center prospective study in PRD patients aged 2-18 years treated with adalimumab and methotrexate (GA-M) or adalimumab alone (GA) for ≥ 12 weeks was performed. Adalimumab concentrations were collected 1-9 (maximum concentration; Cmax), and 10-14 days (minimum concentration; Cmin) during ≥ 12 weeks following adalimumab start. Concentrations were analyzed with enzyme-linked immunosorbent assay (lower limit of quantification: 0.5 mg/L). Log-normalized Cmin were compared between GA-M and GA using a standard t-test.

RESULTS

Twenty-eight patients (14 per group), diagnosed with juvenile idiopathic arthritis (71.4%), non-infectious uveitis (25%) or chronic recurrent multifocal osteomyelitis (3.6%) completed the study. GA-M included more females (71.4%; GA 35.7%, p = 0.13). At first study visit, children in GA-M had a slightly longer exposure to adalimumab (17.8 months [IQR 9.6, 21.6]) compared to GA (15.8 months [IQR 8.5, 30.8], p = 0.8). Adalimumab dosing was similar between both groups (median dose 40 mg every 14 days) and observed DA was low. Children in GA-M had a 27% higher median overall exposure compared to GA, although median Cmin adalimumab values were statistically not different (p = 0.3). Cmin values ≥ 8 mg/L (upper limit RA) were more frequently observed in GA-M versus GA (79% versus 64%). Overall, a wide range of Cmin values was observed in PRD (0.5 to 26 mg/L).

CONCLUSION

This study revealed a high heterogeneity in adalimumab exposure in PRD. Adalimumab exposure tended to be higher with methotrexate co-treatment compared to adalimumab monotherapy although differences were not statistically significant. Most children showed adalimumab exposure exceeding those reported for RA with clinical response, particularly with methotrexate co-treatment. This highlights the need of further investigations to establish model-based personalized treatment strategies in PRD to avoid under- and overexposure.

TRIAL REGISTRATION

NCT04042792 , registered 02.08.2019.

Pharmacokinetics and pharmacodynamics of perfluoropropane after intra-venous bolus injection of perflutren lipid microsphere injection (DEFINITY®) in healthy Chinese volunteers

BACKGROUND AND OBJECTIVE

Definity is an ultrasound contrast agent consisting of phospholipids-encapsulated perfluoropropane (PFP), also known as perflutren, microspheres, which is initially designed to enhance echocardiographic ultrasound images. With no pharmacologic action, Definity can increase the backscatter of ultrasound resulting enhanced ultrasound signals. The objective of this study was to determine the pharmacokinetics (PKs), Pharmacodynamics (PDs) and safety of Definity in healthy male and female Chinese volunteers.

METHODS

A simple GC-MS method was developed and applied to simultaneously quantify PFP both in human whole blood and in expired air using Perfluorobutane (PFB) as internal standard. Meanwhile, the blood microbubble Doppler intensities were continuously monitored as companion PDs by a Doppler ultrasonography system using a non-imaging method.

RESULTS

After intravenous infusion of 10 µL/kg of PFP within 30 seconds, the mean AUClast of the pharmacokinetic analysis set was 0.000653 (uL/mL)*min, the average AUC∞ was 0.001051 (uL/mL)*min. The main coefficient of variation of parameters were within 30%. In this trial, the blood drug concentration of female subjects was lower than that of males. Female Cmax, AUClast and AUC∞ were lower than males', Tmax and t1/2 was close to males', Vss and CL were slightly higher than males'. The concentration of PFP in the expired air of the subject reached the maximum value 1-2 min after administration and the PFP accumulation curve in the expired air began to become flat at 9.5-11 min after administration. The PFP in the expired air at the last sampling point of most subjects was still measurable. The results of the analysis showed that female subjects had slightly more and faster PFP excretion via the lungs than males. The change of blood drug concentration in this trial was related to the change process of Doppler signal intensity. The trend of the two was close, but the peak time of blood drug concentration was slightly delayed compared with the peak time of the Doppler signal intensity. The results showed that female tmax-pd, t10 was earlier than male, and women have lower AUCpd than men.

CONCLUSION

The pharmacokinetics and pharmacodynamics of Definity in blood and expired air were systematically evaluated for the first time in this study. The PK/PD analysis results of this trial showed that the change of blood concentration was related to the change process of Doppler signal intensity, the trend of the two was close and expired air are the main excretion pathways of Definity. Definity was well tolerated by all subjects in the trial.

TRIAL REGISTRATION

This study was registered on 08 December 2017 at the Chinese Clinical Trial Registry (CTR20171087).

Clinical pharmacokinetics and pharmacodynamics of ivosidenib in Chinese patients with relapsed or refractory IDH1-mutated acute myeloid leukemia

PURPOSE

This study aimed to assess the pharmacokinetics (PK) and pharmacodynamics (PD) of ivosidenib in Chinese patients with relapsed or refractory acute myeloid leukemia (R/R AML) carrying the mIDH1 mutation.

METHODS

A bridging study (NCT04176393) was conducted involving 29 Chinese patients who received a daily dose of ivosidenib 500 mg in 28-day cycles. Plasma concentrations of ivosidenib and D-2-hydroxyglutarate (2-HG) were measured before and after treatment. Non-compartmental analysis (NCA) was employed to evaluate the PK, and an established population pharmacokinetic (popPK) model developed from non-Chinese patients was externally validated.

RESULTS

The findings revealed comparable PD effects of ivosidenib in Chinese patients with mIDH1 R/R AML. After adjusting for concomitant drug effects, PK characteristics were similar between Chinese and non-Chinese patients. Furthermore, the popPK model offered additional insights into the possible causes of the apparent ethnic difference in PK exposure.

CONCLUSION

The study indicates that ivosidenib can be used effectively in Chinese patients, and the observed ethnic differences in PK exposure can be explained by concomitant drug effects. The popPK model contributes to a better understanding and optimization of personalized dosing in Chinese patients with mIDH1 R/R AML.

Vincristine-based nanoformulations: a preclinical and clinical studies overview

Vincristine (VCR) is a chemotherapeutic agent obtained from natural alkaloid plant source Catharanthus roseus. VCR has been significantly useful in treatments of lung cancer, lymphocyte-based leukaemia, glioblastomas and acute myeloid leukaemia. VCR attaches to tubulin fibrils and prevents filament polymerization that permanently led to mitosis inhibition in cancer cells. Clinically, VCR is administered to patients in multidrug combination to reduce adverse drug effects and potential blockage of bone marrow inhibition due to prescribed monotherapy. However, VCR possesses low cancer tissue affinity and at higher dose often led to irreversible neurotoxicity. Conventional VCR injectables are successfully used in clinics, but lack of controlled release, non-specific biodistribution and consequent off-target side effects are still major challenges. Currently, nanotechnological drug delivery systems are being explored for improvement of VCR pharmacokinetic profile and tumour-specific targeting. Various nanomedicine formulations such as liposomes, lipid nanoparticles, and polymeric nanocarriers of VCR have been studied under various in vitro and in vivo models. In this review, we have summarised the chemotherapeutic role of VCR, evaluated the mechanism of action, pharmacokinetics and challenges associated with VCR delivery. Moreover, application of VCR in nanomedicine and effect on anticancer efficacy in preclinical and clinical setting are also being discussed.

[Translated article] Pharmacokinetics of eculizumab in adult and pediatric patients with atypical hemolytic uremic syndrome and C3 glomerulopathy

OBJECTIVE

The objective of the study was to analyze and describe the concentrations of eculizumab and the complement blockade in patients with atypical hemolytic uremic syndrome (aHUS) and C3 glomerulopathy, and to define a therapeutic margin where there is a high probability of achieving therapeutic efficacy.

METHODS

Observational, ambispective, and multicenter study that included adult and pediatric patients diagnosed with aHUS and C3 glomerulopathy from September 2020 to October 2022 in 5 hospitals in Spain. Eculizumab was administered at the doses recommended by the data sheet according to the European Medicines Agency (EMA). Pre- and post-dose concentrations of eculizumab were determined, as well as blockade of the classical complement pathway (CH50). Sociodemographic and clinical data were collected, and pharmacokinetic parameters were calculated. To establish the cut-off point for eculizumab concentrations that predicted complement blockade, Receiver Operating Characteristic (ROC) curve analysis was performed. Lastly, the Kruskal-Wallis test was used to contrast the differences in different parameters according to eculizumab concentrations.

RESULTS

Twenty-five patients were included, 19 adults (76.0%) and 6 pediatrics (24.0%), with median ages of 43.4 (interquartile range (IQR) 35.7-48.8) and 10.1 (IQR 9.6-11.3) years, respectively. Of these, 22 (88.0%) patients were diagnosed with aHUS and 3 (12.0%) with C3 glomerulopathy. A total of 111 eculizumab concentrations were determined. Mean pre- and post-dose concentration values detected during the maintenance phase were 243.8 (SD 240.6) μg/mL and 747.4 (standard deviation (SD) 444.3) μg/mL, respectively. Increased complement blockade was observed at higher pre-dose concentrations (P = .002) and decreased serum creatinine at both higher pre- and post-dose concentrations (P = .001 and P = .017, respectively). Using ROC curves, it was determined that a pre-dose concentration >149.0 μg/mL was optimal to achieve complement blockade, with an AUC of 0.87 (0.78-0.95). Finally, high inter-individual (48.9% variation coefficient (CV)) with low intra-individual variabilities (11.9% CV) in eculizumab clearance were observed.

CONCLUSIONS

The present study reports supratherapeutic concentrations of eculizumab in patients with aHUS, and defines higher concentrations than those described in the data sheet to achieve blockade, thus encouraging the personalization of treatment with eculizumab.

Early assessment of the pharmacokinetic and pharmacodynamic effects following acetylsalicylic acid loading: toward a definition for acute therapeutic response

Despite decades of investigations, the optimal assessment of the "therapeutic response" to early after loading dose of acetylsalicylic acid (ASA) remains unclear. Limited information is available on the relation between pharmacodynamic (PD) and pharmacokinetic (PK) measurements assessed immediately after ASA administration. Serial PD and PK analyses were performed immediately after a single 162 or 650 mg dose of chewed and swallowed ASA in ten healthy adults. ASA response was defined as > 95% inhibition of serum thromboxane (Tx)B2, < 550 aspirin reaction units (ARU) by VerifyNow Aspirin (VN) test, and ≤ 20% arachidonic acid (AA)-induced platelet aggregation (PA). Correlation analyses between PK and PD measurements and receiver operating characteristic (ROC) curve analyses were performed. ASA response measured by VN test and AA-induced PA was achieved within 30 min of ASA administration. A correlation was observed between ARU and AA-induced maximum PA (r = 0.69, p < 0.001), serum TxB2 (r = 0.74 and p < 0.001), and serum TxB2 inhibition (r = 0.79, p < 0.001). In ROC curve analyses, ≤ 558 ARU and ≤ 7% AA-induced PA were associated with > 95% inhibition of TxB2. 686 ng/ml plasma ASA cut-off point was associated with > 95% inhibition of serum TxB2, ≤ 7% 1 mM AA-induced PA, and ≤ 585 ARU. A modest ~ 50% inhibition of TxB2 inhibition was associated with marked inhibition of 1 mM AA-induced platelet aggregation by LTA. Our analyses demonstrated important relationships between pharmacodynamic, and pharmacokinetic parameters measured immediately following oral ASA and cutoff values for ARU and AA-induced PA that is associated with > 95% inhibition of serum TxB2.

Pharmacokinetics of eculizumab in adult and pediatric patients with atypical hemolytic uremic syndrome and C3 glomerulopathy

OBJECTIVE

The objective of the study was to analyze and describe the concentrations of eculizumab and the complement blockade in patients with atypical hemolytic uremic syndrome (aHUS) and C3 glomerulopathy, and to define a therapeutic margin where there is a high probability of achieving therapeutic efficacy.

METHODS

Observational, ambispective and multicenter study that included adult and pediatric patients diagnosed with aHUS and C3 glomerulopathy from September 2020 to October 2022 in five hospitals in Spain. Eculizumab was administered at the doses recommended by the data sheet according to the European Medicines Agency (EMA). Pre-dose and post-dose concentrations of eculizumab were determined, as well as blockade of the classical complement pathway (CH50). Sociodemographic and clinical data were collected, and pharmacokinetic parameters were calculated. To establish the cut-off point for eculizumab concentrations that predicted complement blockade, Receiver Operating Characteristic (ROC) curve analysis was performed. Lastly, the Kruskal-Wallis test was used to contrast the differences in different parameters according to eculizumab concentrations.

RESULTS

Twenty-five patients were included, 19 adults (76.0%) and 6 pediatrics (24.0%), with median ages of 43.4 (IQR 35.7-48.8) and 10.1 (IQR 9.6-11.3) years, respectively. Of these, 22 (88.0%) patients were diagnosed with aHUS and 3 (12.0%) with C3 glomerulopathy. A total of 111 eculizumab concentrations were determined. Mean pre-dose and post-dose concentration values detected during the maintenance phase were 243.8 (SD 240.6) μg/mL and 747.4 (SD 444.3) μg/mL, respectively. Increased complement blockade was observed at higher pre-dose concentrations (p=0.002) and decreased serum creatinine at both higher pre- and post-dose concentrations (p=0.001 and p=0.017, respectively). Using ROC curves, it was determined that a pre-dose concentration >149.0 μg/mL was optimal to achieve complement blockade, with an AUC of 0.87 (0.78-0.95). Finally, high inter-individual (48.9% CV) with low intra-individual variabilities (11.9% CV) in eculizumab clearance were observed.

CONCLUSIONS

The present study reports supratherapeutic concentrations of eculizumab in patients with aHUS, and defines higher concentrations than those described in the data sheet to achieve blockade, thus encouraging the personalization of treatment with eculizumab.

Preparation, in vitro and in vivo evaluation of a novel mitiglinide microemulsions

This study aimed to prepare an o/w mitiglinide microemulsion (MTGME) to improve the drug solubility and bioavailability. The formulation of o/w MTGME was optimized by the solubility study of drug, pseudo-ternary phase diagram and Box-Behnken design successively. MTGME was characterized by dynamic laser light scattering (DLS), zeta potential and transmission electron microscopy (TEM), moreover, the storage stability, pharmacodynamics and pharmacokinetics were investigated. The optimal prescription for MTGME consisted of Maisine 35-1 (oil), Cremophor EL (surfactant) and propylene glycol (PG, cosurfactant). MTGME with a spherical dimension of 58.1 ± 5.86 nm was stable when stored at 4 °C for 3 months. The blood glucose levers (BGL) of diabetic mice were uniformly and significantly decreased by intragastric (i.g.) administration of 1-4 mg/kg MTGME, in which BGL (i.g. 4 mg/kg MTGME) was reduced by 69% during 24 h. The pharmacokinetics study of MTGME (i.g., 20 mg/kg) in Wistar rats showed higher plasma drug concentration (Cmax, 2.9 folds), larger area under curve (AUC, 4.6 folds) and oral bioavailability than those of MTG suspensions. Generally, the MTGME (o/w) showed good effect on controlling hyperglycemia. Therefore, microemulsion can be used as an effective oral drug delivery system to improve the bioavailability of MTG.

In vivo efficacy and PK/PD analyses of zifanocycline (KBP-7072), an aminomethylcycline antibiotic, against Acinetobacter baumannii in a neutropenic murine thigh infection model

INTRODUCTION

Zifanocycline (KBP-7072) is a novel aminomethylcycline antibiotic with a broad spectrum of antibacterial activity. This study determined the pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of zifanocycline in mice and the optimal PK/PD index for efficacy against Acinetobacter baumannii in a neutropenic murine thigh infection model.

METHODS

Zifanocycline PK properties were characterized in plasma after single-dose subcutaneous injection in healthy mice at doses of 1, 4, 16, 64, and 256 mg/kg. PK/PD analyses were performed with zifanocycline against 8 clinical A. baumannii isolates in a neutropenic murine thigh infection model.

RESULTS

Plasma total and free drug Cmax, AUC0-inf, and AUC0-24 increased with dose, where Cmax of total drug was 0.12-25.2 mg/L, AUC0-inf was 1.13-234 h*mg/L, AUC0-24 was 1.09-225 h*mg/L, and free drug Cmax was 0.03-5.68 mg/L, AUC0-inf was 0.25-52.6 h*mg/L, and AUC0-24 was 0.25-50.5 h*mg/L. MICs of zifanocycline against A. baumannii ranged from 0.06 to 0.5 mg/L, with significant activity against all 8 strains. Average daily doses of zifanocycline to achieve a static, 1-log10 kill, and 2-log10 kill effect were projected to be 6.92, 9.63, and 13.22 mg/kg, and the mean fAUC/MIC ratios were 6.91, 9.10, and 12.60, respectively. AUC/MIC was the optimal PK/PD index of zifanocycline against A. baumannii.

CONCLUSION

The in vivo efficacy results and PK/PD analyses support the design of optimal dosing regimens in clinical studies and assist with determining clinical breakpoints for zifanocycline.

Therapeutic drug monitoring of glycopeptide antimicrobials: An overview of liquid chromatography-tandem mass spectrometry methods

Therapeutic drug monitoring (TDM) is a critical clinical tool used to optimize the safety and effectiveness of drugs by measuring their concentration in biological fluids. These fluids are primarily plasma or blood. TDM, together with real-time dosage adjustment, contributes highly to the successful management of glycopeptide antimicrobial therapies. Understanding pharmacokinetic/pharmacodynamic (PK/PD) properties is vital for optimizing antimicrobial therapies, as the efficacy of these therapies depends on both the exposure of the patient to the drug (PK) and pharmacodynamic (PD) parameters such as the in vitro estimated minimum drug concentration that inhibits bacterial growth (MIC). Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) is widely recognized as the gold standard for measuring small molecules, such as antibiotics. This review provides a comprehensive overview of LC-MS/MS methods available for TDM of glycopeptide antibiotics, including vancomycin, teicoplanin, dalbavancin, oritavancin, and telavancin.