Gilead Sciences, a biopharmaceutical company, has started enrolling patients in a Phase II clinical trial of cicletanine hydrochloride, an oral agent in development for the treatment of pulmonary arterial hypertension.
The study is designed to compare the efficacy, safety and tolerability of cicletanine to placebo in patients with pulmonary arterial hypertension (PAH) and will enroll 160 patients at approximately 60 investigational sites worldwide.
The cicletanine Phase II study is a randomized, double-blind, placebo-controlled, multicenter, dose-ranging study designed to evaluate the safety, efficacy and tolerability of cicletanine for treatment of PAH (WHO Group 1). The primary efficacy endpoint is the change from baseline in six-minute walk distance after 12 weeks of treatment.
Secondary endpoints include time to clinical worsening of PAH during the 12-week placebo-controlled treatment period and change from baseline after 12 weeks in Borg dyspnea index, WHO functional class, SF-36A Health Survey physical functioning scale and various hemodynamic measures. Eligible patients include those not currently receiving treatment for PAH as well as those who are currently being treated with an approved endothelin receptor antagonist.
A total of 160 patients (40 per treatment arm) will be randomized (1:1:1:1) to receive either placebo, 150mg cicletanine administered once daily, 150mg cicletanine administered twice daily or 300mg administered once daily. Patients who complete the 12-week placebo-controlled period will be eligible for long-term treatment with cicletanine.
Seigo Izumo, senior vice president of cardiovascular therapeutics of Gilead, said: Preclinical and early clinical data suggest that cicletanine may offer an alternative oral treatment for PAH, potentially working through a mechanism of action that differs from existing therapies for this disease.