Clinical Pharmacology & Therapeutics最新文献

This study was designed to assess the quantitative performance of endogenous drug-drug interaction (DDI) biomarkers (N1-methylnicotinamide (1-NMN), N1-methyladenosine (m¹A), and creatinine) for the organic cation transporters, OCT2 and MATE1/2K in the kidney. Ten healthy volunteers received cimetidine (400 and 800 mg, single dose) or dolutegravir (50 mg, twice a day) together with metformin (500 mg). Cimetidine and dolutegravir were considered to act mainly as MATE1/2K and OCT2 inhibitors, respectively. The renal clearance (CL_r) of metformin was decreased by 15.5% and 42.5% by cimetidine 400 and 800 mg, and by 26.8% and 56.9% by dolutegravir first and fifth doses, respectively. CL_r ratio (CL_rR) of 1-NMN were 0.93 and 0.64 for cimetidine 400 and 800 mg, and 0.87 and 0.47 for dolutegravir first and fifth doses, respectively. CL_rR of m¹A was less than that of 1-NMN: 1.0 and 0.80 for cimetidine 400 and 800 mg, and 0.77 and 0.71 for dolutegravir first and fifth doses, respectively. CL_r of creatinine was significantly decreased only by cimetidine 800 mg. Individual CL_rR of 1-NMN and m¹A showed a positive correlation with the corresponding CL_rR of metformin with r² of 0.58 and 0.55, respectively. When evaluated individually, m¹A showed a better correlation during cimetidine periods (r² 0.64) than 1-NMN (r² 0.36), but vice versa during dolutegravir periods (r² 1-NMN, 0.80; m¹A, 0.32). These results suggest that 1-NMN and m¹A might be more promising than creatinine as endogenous biomarkers for quantitatively assessing the DDI potential of investigational drugs for OCT2 and MATE1/2K based on their CL_rR change.

An over-the-counter product berberine (a major alkaloid in goldenseal) is a substrate of the uptake transporter OCT1 and the metabolizing enzyme CYP2D6. The two genes exhibit common functional polymorphisms. Approximately 9% of Europeans and white Americans are either poor CYP2D6 metabolizers or poor OCT1 transporters. In this study, we investigated the effects of OCT1 and CYP2D6 polymorphisms on berberine pharmacokinetics in humans. We confirmed in vitro that berberine is an OCT1 substrate (K_M of 7.0 μM, CL_int of 306 ± 29 μL/min/mg). Common OCT1 alleles *3 to *6 showed uptake reduced by at least 65% and Oct1/2 knockout mice showed 3.2-fold higher AUCs in liver perfusion experiments. However, in humans, poor OCT1 transporters did not show any differences in berberine pharmacokinetics compared with reference participants. In contrast, CYP2D6 polymorphisms significantly affected berberine metabolism, but exclusively in females. Females who were poor CYP2D6 metabolizers had an 80% lower M1-to-berberine ratio. General linear model analyses suggest strong synergistic, rather than additive, effects between female sex and CYP2D6 genotype. Overall, berberine displayed low oral bioavailability, yet females had a 2.8-fold higher AUC and a 3.6-fold higher C_max than males (P < 0.001). These effects were only partially attributable to the sex-CYP2D6 genotype interaction. In conclusion, despite berberine being an OCT1 substrate, OCT1 deficiency did not affect berberine pharmacokinetics in humans. In contrast, CYP2D6 emerges as a critical enzyme for berberine metabolism in females, but not in males, highlighting sex-specific differences. We suggest that factors beyond CYP2D6 metabolism are determining berberine's systemic exposure, especially in males (NCT05463003).

The association between direct-acting antiviral (DAA) treatment and hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) is currently unclear. Hence, we aim to assess the association between DAA treatment and mortality rate among Medicare beneficiaries with HCV-related HCC. This retrospective cohort study screened 19,813 adults in 2013-2019 Surveillance, Epidemiology, and End Results data linked with Medicare data. Patients with HCV-related HCC initiating DAA therapy after their first HCC diagnosis were compared with patients with HCV-related HCC who received no HCV treatment. After inverse probability treatment weighting, multivariable Cox proportional hazards models compared mortality rates between the groups. Subgroup and sensitivity analyses were based on HCC stage (early vs. advanced), type of HCC treatment (curative, palliative, none), and DAA treatment duration. In total 3,777 patients with HCV-related HCC were identified (mean age: 68.2 years, 75.2% male, 61.8% White), of whom 19% initiated DAA therapy. Crude incidence mortality rates were 17.9 and 90.7 deaths per 100 person-years in the DAA and HCV-untreated groups, respectively. Cox regression models indicated that DAA therapy was associated with decreased risk of all-cause mortality (adjusted hazard ratio, 0.33; 95% CI 0.31-0.36). Median survival time was 45.7 (95% CI 40.9-57.9) months in the DAA group and 7.7 (95% CI 7.3-8.2) months in the HCV-untreated group (P < 0.001). All subgroup and sensitivity analyses were consistent with the main analyses. DAA therapy was associated with survival benefits for patients with HCV-related HCC regardless of the stage or type of HCC treatment and should not be withheld from this population of Medicare beneficiaries.

Burosumab is approved for the treatment of hypophosphatemia in persistent tumor-induced osteomalacia. This work exemplifies a model-informed drug development approach that evaluated burosumab pharmacokinetics and pharmacokinetic/pharmacodynamics in the ultrarare tumor-induced osteomalacia population to support adult and pediatric dosing. Data from tumor-induced osteomalacia participants were combined with data from X-linked hypophosphatemia to understand pharmacokinetic and pharmacokinetic/pharmacodynamic characteristics and covariates specific to tumor-induced osteomalacia. Pharmacokinetic and pharmacokinetic/pharmacodynamic simulations were performed using final models to support dosing recommendations for adults and extrapolation to pediatric patients. Burosumab pharmacokinetics were described using a one-compartment model with first-order absorption and body weight as a significant covariate. Pharmacokinetic/pharmacodynamic relationships were described using a sigmoidal Emax model with significant covariates of baseline fibroblast growth factor 23 on baseline fasting serum phosphate and potency of burosumab response and tumor-induced osteomalacia disease state resulting in a steep slope of response; however, the covariates are not clinically meaningful. Simulations demonstrated that, in pediatric patients, starting doses of burosumab 0.3 and 0.4 mg/kg every 2 weeks at steady state would achieve normal serum phosphate levels in ≥ 30% of patients with relatively low risk of hyperphosphatemia (< 3%). In adults, burosumab 0.3 and 0.5 mg/kg every 4 weeks achieves similar percentages of responders and a relative low risk of hyperphosphatemia (< 7%). Serum phosphate titration-based burosumab dosing increased the probability of achieving normal serum phosphate levels. The models supported a model-informed drug development approach for global approvals of titration-based burosumab dosing, guided by monitoring fasting serum phosphate levels.

The IQ CPLG Organ Impairment WG conducted a survey to understand how various IQ member companies develop dosing recommendations for patients with renal impairment. Eighteen IQ member companies participated in the survey. The survey results were summarized by the working group in light of the regulatory renal impairment guidance documents as well as recent publications from the pharmaceutical industry and nephrology community. There were two important learnings from the survey: (i) pharmaceutical companies do not use a consistent methodology to assess renal function in their drug development programs. (ii) there has been significant improvement in predicting how kidney function affects drug pharmacokinetics (PK) and thus dose recommendations. Applying model-based methods such as population PK, physiologically-based PK (PBPK), and virtual controls has enabled earlier prediction of how kidney function influences PK, leading to the participation of more patients with impaired kidney function in Phase 2 and 3 trials.

Pompe disease is a rare glycogen storage disease caused by mutations in the enzyme acid α-glucosidase (GAA) resulting in pathological accumulation of glycogen in muscle tissues leading to progressive weakness and respiratory dysfunction. Enzyme replacement therapy (ERT) with GAA is currently the sole treatment option for patients with Pompe disease. ERT burdens patients with frequent intravenous infusions while insufficiently halting disease progression due to incomplete ERT skeletal muscle distribution. Glycogen synthase 1 (GYS1) has been proposed as a substrate reduction therapy (SRT) target for Pompe disease. Here, we report results from the first-in-human study of the orally available GYS1 inhibitor MZE001 in healthy subjects. In 88 participants, MZE001 was well-tolerated up to a single dose of 480 mg BID and multiple doses of 720 mg BID for 10 days. Noncompartmental analysis determined that the half-life and C_trough concentrations of MZE001 could provide efficacious exposures with once or twice daily oral dosing. Change from baseline of peripheral blood mononuclear cell (PBMC) glycogen, which correlated with muscle glycogen levels in preclinical models, was significantly reduced dose-dependently following 10 days of MZE001 treatment in healthy subjects. A muscle biopsy sub-study demonstrated that 10 days of MZE001 (480 mg BID) dosing safely and substantially lowered muscle glycogen stores in healthy adults. This correlated with the PBMC exposure response and supports the use of PBMC glycogen reduction as a surrogate for muscle response, and MZE001 potential for development as the first oral substrate reduction therapy for patients with Pompe disease.

Methadone has a high potential for risky drug-drug interactions that can lead to opioid overdose, yet evidence on the magnitude of this risk remains limited. Since methadone is transported via P-glycoprotein (P-gp), the use of statins that inhibit P-gp may elevate methadone plasma concentrations, potentially leading to opioid overdose. We explored this hypothesis by examining whether concomitant use of methadone and P-gp-inhibiting statins was associated with opioid overdose. Using Medicaid claims data from 2003 to 2020, we conducted a cohort study among new concomitant users of methadone and statins. We compared overdose rates among individuals exposed to P-gp-inhibiting statins (simvastatin, atorvastatin, or lovastatin) vs. those exposed to rosuvastatin (negative control), adjusting for baseline covariates. We identified 69,263 individuals newly exposed to methadone and a statin of interest; the overall incidence rate of opioid overdose was 26.0 per 1,000 person-years. Adjusted hazard ratios (HRs) for methadone + P-gp-inhibiting statins consistently showed no association, ranging from 0.76 (95% CI = 0.48-1.22) for atorvastatin to 0.78 (95% CI = 0.50-1.22) for simvastatin, compared with methadone + rosuvastatin. Similar results were observed in sensitivity analysis that treated all P-gp-inhibiting statins as a single exposure group, as well as analyses stratified by baseline diagnosis of opioid use disorder or overdose, the duration of baseline methadone use, and calendar year intervals. Our findings suggest that concomitant use of methadone with simvastatin, atorvastatin, or lovastatin is not associated with the risk of opioid overdose compared to concomitant use of methadone and rosuvastatin.

The International Coalition of Medicines Regulatory Authorities (ICMRA), comprising 38 global medicines regulatory authorities, collaborates on shared challenges, notably during the COVID-19 pandemic. This article focuses on the ICMRA COVID-19 Real-World Evidence (RWE) and Observational Studies Working Group. The Working Group aimed to address challenges related to RWE and observational studies during the pandemic, resulting in impactful studies and ICMRA statements on international collaboration for RWE and COVID-19 vaccine safety. Reflecting on 3 years of collaboration, the Working Group surveyed members for insights, and recommendations were formulated to enhance research preparedness, collaboration, and response to future public health emergencies. The lessons learned highlight the importance of global collaborations, governance structures for rapid decision-making, and effective utilization of existing networks. Recommendations include the establishment of an international governance structure, a "coalition of the willing" for swift research collaboration, dedicated sub-groups, periodic workshops, common protocols, joint timelines, and data model templates, leveraging existing infrastructure, and strengthening outreach for transparency and engagement. The Working Group envisions repurposing into an RWE strategic and operational entity, contributing to global public health emergency response mechanisms. In conclusion, the Working Group's success lies in effective communication, collaborative research, and leveraging existing infrastructure, with ongoing contributions to global emergency response mechanisms.

Sodium-glucose cotransporter 2 (SGLT2) inhibitors can cause a reversible decline in glomerular filtration rate (GFR), which may influence dosing recommendations for renally excreted medications. In practice, GFR is typically estimated by serum creatinine concentration, but creatinine may not be a reliable indicator of GFR decline in the setting of SGLT2 inhibitor use. Alternative filtration markers such as cystatin C, β-trace protein (BTP), and β2-microglobulin (B2M) may be more appropriate, but little is known about how these markers are affected by SGLT2 inhibitor use. Therefore, we determined creatinine, cystatin C, BTP, and B2M concentration in a crossover study of 35 people with type 2 diabetes receiving 12 weeks of dapagliflozin treatment or placebo. Estimated GFR (eGFR) based on creatinine (eGFRcre), cystatin C (eGFRcys), their combination (eGFRcomb), or a panel of all four markers (eGFRpanel) was compared with measured GFR (mGFR) based on plasma clearance of chromium-51 labeled ethylenediamine tetraacetic acid (⁵¹Cr-EDTA). Dapagliflozin treatment was associated with a significant decrease in mGFR (-9 mL/min/1.73 m², P < 0.001) but not a corresponding increase in concentration of any filtration marker. No eGFR equation accurately predicted change in mGFR between treatment periods, but eGFRcomb and eGFRpanel yielded the highest overall accuracy relative to mGFR across both treatment periods. These findings highlight the stability in performance gained by combining multiple filtration markers but suggest that eGFR in general is not an ideal metric for assessing short-term GFR decline in people initiating SGLT2 inhibitor therapy.