A Parallel Design Study to Assess the Bioequivalence of Generic and Branded Hydroxychloroquine Sulfate Tablets in Healthy Volunteers

Predicting Hydroxychloroquine Clearance in Healthy and Diseased Populations Using a Physiologically Based Pharmacokinetic Approach

Hydroxychloroquine (HCQ), a congener of chloroquine, is widely used in prophylaxis and the treatment of malaria, and also as a cure for rheumatoid arthritis, systemic lupus erythematosus, and various other diseases. Physiologically based pharmacokinetic modeling (PBPK) has attracted great interest in the past few years in predicting drug pharmacokinetics (PK). This study focuses on predicting the PK of HCQ in the healthy population and extrapolating it to the diseased populations, i.e., liver cirrhosis and chronic kidney disease (CKD), utilizing a systematically built whole-body PBPK model. The time vs. concentration profiles and drug-related parameters were obtained from the literature after a laborious search and in turn were integrated into PK-Sim software for designing healthy intravenous, oral, and diseased models. The model's evaluation was performed using observed-to-predicted ratios (Robs/Rpre) and visual predictive checks within a 2-fold error range. The healthy model was then extrapolated to liver cirrhosis and CKD populations after incorporating various disease-specific pathophysiological changes. Box-whisker plots showed an increase in AUC_0-t in liver cirrhosis, whereas a decrease in AUC_0-t was seen in the CKD population. These model predictions may assist clinicians in adjusting the administered HCQ doses in patients with different degrees of hepatic and renal impairment.

Pharmacokinetics, Bioequivalence, and Safety of 2 Formulations of Hydroxychloroquine Tablets in Healthy Chinese Volunteers Under Fasting and Fed Conditions

The purpose of this trial was to evaluate the pharmacokinetics (PK), bioequivalence (BE), and safety of 2 preparations of hydroxychloroquine (200-mg tablet) under fasting and fed conditions. A total of 180 subjects (fasting condition: n = 80; fed condition: n = 100) were randomly enrolled in this randomized, open, single-dose, single-cycle parallel phase Ⅰ clinical study. Under the 2 conditions, the subjects were randomly administered the test (T) or reference (R) tablet, both at a dose of 200 mg (1 tablet). Liquid chromatography-tandem mass spectrometry was used to determine the concentration of hydroxychloroquine in healthy subjects after oral administration of the T or R preparation to evaluate the PK characteristics. In this trial, the T and R preparations of hydroxychloroquine were bioequivalent under both conditions within the range of 80%-125%. No serious adverse events (SAEs) were found in the safety assessments for either condition, and all adverse events (AEs) were mild, except for 2 moderate AEs in the fed condition, indicating good safety.

Pharmacokinetics and Safety of Dapoxetine Hydrochloride in Healthy Chinese Men: Impact of Dose and High-Fat Meal

Dapoxetine is the first oral medication specifically developed for the on-demand treatment of premature ejaculation. The pharmacokinetics and safety of 30 mg (n = 40) and 60 mg (n = 38) dapoxetine in healthy Chinese under fasted and fed states were assessed in 2 studies. Both studies are random, single-center, 2-period, open-label, 2-way crossover designs. Plasma concentration of dapoxetine was determined by high-performance liquid chromatography-tandem mass spectrometry, and the pharmacokinetic parameters were calculated using noncompartmental analysis. Dapoxetine was quickly absorbed and reached maximum concentration 1 to 3 hours after oral administration. Elimination was biphasic, and the plasma concentration decreased to 3% to 7% of maximum concentration by 24 hours while half-life was 15 to 18 hours. Meantime, high-fat meals slightly increased its exposure. Both doses of dapoxetine were well tolerated. The adverse events in the high-dose group under fasted and fed states were 37.9% and 19.0%, respectively.