CPT: pharmacometrics & systems pharmacology
-
CPT Pharmacometrics Syst Pharmacol · Oct 2017
Randomized Controlled TrialPopulation Exposure-Response Modeling Supported Selection of Naloxegol Doses in Phase III Studies in Patients With Opioid-Induced Constipation.
Naloxegol is approved for the treatment of opioid-induced constipation (OIC) in adults with chronic noncancer pain. Population exposure-response models were developed using data from a phase II study comprising 185 adults with OIC. ⋯ The model predicted that 12.5, 25, and 37.5 mg doses would produce median response rates of 40%, 50%, and 60%, and dropout rates of 13.3%, 16.7%, and 23.3%, respectively. The large overlap of predicted difference of the response rate between placebo and the 25 or 37.5 mg doses suggested little utility of using a 37.5 mg dose in phase III studies.
-
CPT Pharmacometrics Syst Pharmacol · Jul 2017
Randomized Controlled Trial Multicenter StudyPopulation Modeling of Selexipag Pharmacokinetics and Clinical Response Parameters in Patients With Pulmonary Arterial Hypertension.
Selexipag (Uptravi) is an oral selective IP prostacyclin receptor agonist approved for the treatment of pulmonary arterial hypertension (PAH). The pivotal GRIPHON study was the largest clinical study ever conducted in PAH patients, providing long-term data from 1,156 patients. ⋯ Using log-linear regression models linking model-predicted steady-state exposure to pharmacodynamics (PD), exposure to selexipag and ACT-333679 showed some statistically significant, albeit not clinically relevant, effects on exercise capacity, laboratory values, and the occurrence of prostacyclin-related adverse events, but not on vital signs or adverse events denoting hemorrhage. Using suitable modeling techniques, the GRIPHON study yielded clinically relevant data with limited burden of pharmacokinetics (PK) blood sampling, demonstrating that PK/PD modeling enables firm conclusions even with sparse PK and PD sampling.