Nonlinear relationship between enteric-coated mycophenolate sodium dose and mycophenolic acid exposure in Han kidney transplantation recipients

The aim of the research was to investigate the pharmacokinetics (PK) of enteric-coated mycophenolate sodium (EC-MPS) by quantification of the active metabolite of mycophenolic acid (MPA) after multiple escalating oral doses in Han kidney transplant recipients. A total of 28 Han postoperative kidney transplant recipients were given a multiple-dose of 540, 720 or 900 mg of EC-MPS two times a day in combination with tacrolimus for 6 days. Blood specimens were collected at each time point from 0 to 12 h after EC-MPS administration. MPA plasma concentrations were measured by UPLC-UV. The relationship between the EC-MPS dose and its PK parameters was assessed. In the range from 540 to 900 mg,and AUCdid not increase with dose escalation. The AUC,,andfor the 540 720 and 900 mg doses were not significantly different, respectively (>0.05). AUCandwere increased less than proportionally with increasing EC-MPS dose levels. Inter-individual variability in AUC,andwere considerable. Nonlinear PK relationships were found from the doses of 540-900 mg of EC-MPS.

Study on Bioequivalence of Acetylcysteine Granules in Chinese Healthy Volunteers / 医药导报

Objective To establish an analytical method for assessing acetylcysteine in human plasma and study the relative bioavailability and bioequivalence of acetylcysteine granules in Chinese healthy volunteers. Methods In the randomized crossover study, 24 healthy male volunteers received a single oral dose of 0. 6 g test acetylcysteine granules, reference acetylcysteine granules or no medication. The plasma concentration of acetylcysteine was determined by LC-MS/MS. Pharmacokinetic parameters were calculated and bioequivalence of two preparations were evaluated by DAS3. 0 software. Results The main pharmacokinetic parameters of the test and reference preparations were as follows:AUC0→t was (8 547. 64± 2 860.04) and (8 783.07±4 042. 10) μg·h·L-1, respectively; AUC0→∞ was (9 481. 64±3 444. 76) and (9 540. 51± 4 239. 30) μg·h·L-1, respectively;Cmax was (1 994. 39±726. 42) and (2 090. 27±885. 46) μg·L-1, respectively;tmax was (1.18±0. 60) and (1. 13±0. 53) h, respectively; t1/2 was (8. 60±3. 76) and (7. 75±5. 01) h, respectively. The relative bioavailability F0→t and F0→∞ was ( 107. 0 ± 43. 3 )% and ( 106. 5 ± 40. 1 )%, respectively. Conclusion The results of statistical analysis indicate that the test and reference formulations are bioequivalent.