Masanao Isono

The Pharmacokinetics of Beraprost Sodium Following Single Oral Administration to Subjects With Impaired Kidney Function

The purpose of the present study was to evaluate the pharmacokinetics of beraprost sodium (BPS) and its active enantiomer, BPS‐314d, in Japanese subjects with impaired kidney function. The plasma and urine concentrations of BPS and BPS‐314d were measured following the single oral administration of 120 μg of BPS as the sustained‐release tablet, TRK‐100STP, under fasting conditions to 18 subjects with impaired kidney function (stage 2, 3, and 4 chronic kidney disease [CKD] as categorized by the estimated glomerular filtration rate) and to 6 age‐, body weight‐, and gender‐matched subjects with normal kidney function (stage 1 CKD). The Cmax values (mean ± SD) of BPS in stage 1, 2, 3, and 4 CKD, respectively, were 84.9 ± 22.9, 119.8 ± 36.4, 190.6 ± 137.3, and 240.2 ± 110.5 pg/mL; its AUC0‐48h were 978 ± 226, 1252 ± 427, 1862 ± 964, and 1766 ± 806 pg·h/mL, respectively, and its cumulative urinary excretion rates were 0.704 ± 0.351%, 0.638 ± 0.292%, 0.485 ± 0.294%, and 0.159 ± 0.136%. The Cmax values of BPS‐314d were 22.4 ± 6.4, 30.8 ± 8.5, 46.7 ± 30.6, and 54.4 ± 25.2 pg/mL, its AUC0‐48h were 155 ± 56, 226 ± 67, 341 ± 176, and 329 ± 143 pg·h/mL, and its cumulative urinary excretion rates were 0.428 ± 0.242%, 0.349 ± 0.179%, 0.356 ± 0.270%, and 0.096 ± 0.099%, respectively. Adverse events were reported in 2 subjects with stage 2 CKD and 1 subject with stage 4 CKD. The Cmax and AUC0‐48h of BPS and BPS‐314d were higher based on the severity of impaired kidney function. No relationship was observed between the incidence of adverse events and the severity, and tolerability was confirmed. We consider that dose adjustment is not necessary, but BPS is more carefully treated in patients with impaired kidney function.

A multinational phase IIb/III trial of beraprost sodium, an orally active prostacyclin analogue, in patients with primary glomerular disease or nephrosclerosis (CASSIOPEIR trial), rationale and study design.

BackgroundChronic kidney disease (CKD) is public health concern even in Asian countries. TRK-100STP, a sustained release tablet of an orally-active prostacyclin analogue, beraprost sodium, is suggested to suppress worsening of some parameters of renal filtration function, containing in slope of 1/serum creatinine (1/SCr) vs. time in a phase II clinical trial.Methods/designWe describe the design of the phase IIb/III trial of TRK-100STP, CASSIOPEIR (CRF Asian Study with Oral PGI2 derivative for Evaluating Improvement of Renal function) conducted in approximately 160 centers in China, Hong Kong, Japan, Malaysia, Republic of Korea, Taiwan, and Thailand. A total of 750 patients (n = 250 per group) with primary glomerular disease or nephrosclerosis were planned to be enrolled. Patients were randomized into one of three treatment groups in a double-bind, placebo-controlled manner: TRK-100STP 60 μg b.i.d.; TRK-100STP 120 μg b.i.d.; or placebo. The treatment period is planned to last 2 to 4 years. The primary efficacy endpoint is the renal composite endpoint including doubling of SCr and ESRD (dialysis induction, renal transplantation, or increase in SCr to ≥6.0 mg/dL).DiscussionThis trial targeting CKD patients is designed to (a) demonstrate the superiority of TRK-100STP over placebo using renal composite endpoints, (b) determine the recommended clinical dose, and (c) assess the safety of TRK-100STP in this population and setting.Trial registrationClinicalTrials.gov Identifier: NCT01090037.