EPIX Pharmaceuticals, has initiated its Phase 2b right-heart catheter study of PRX-08066 in adult patients with chronic obstructive pulmonary disease and moderate-to-severe pulmonary hypertension.
PRX-08066 is a serotonin type 2B receptor (5-HT2B) antagonist that may represent a new mechanism of action for treating pulmonary hypertension without affecting systemic blood pressure, according to the Lexington, Mass.-based EPIX.
The company said that expression of the 5-HT2B receptor is increased in the pulmonary arteries of patients with pulmonary hypertension and blocking the 5-HT2B receptor may reduce or prevent the acute rise in pulmonary blood pressures which occurs when patients increase their activity.
The company said its single-arm, open-label, Phase 2b study will evaluate the mean pulmonary artery blood pressure change from baseline as measured directly by right-heart catheterization, and will also measure the change from baseline in the standard six-minute walk distance test after three months of treatment. Patients will be treated with 500 mg of PRX-08066 from the start of the trial followed by twice-daily dosing of 300 mg of PRX-08066 for three months.