Arena Pharmaceuticals passed the first test of its drug development comeback strategy by delivering positive results from a mid-stage study targeting pulmonary arterial hypertension (PAH), a rare and debilitating disease caused by high blood pressure in the arteries that connect the heart to the lungs.
In the study of 61 PAH patients already on standard background therapy, Arena’s experimental drug ralinepag reduced pulmonary vascular pressure by 30 percent compared to a placebo. The difference was statistically significant, achieving the primary endpoint of the study. Pulmonary vascular pressure measures the pressure inside the arteries connecting the lungs with the heart.
Investors were hoping to see a 20 percent to 25 percent placebo-adjusted decrease in pulmonary vascular resistance as positive and clinically meaningful evidence of the drug’s activity in PAH. Arena hit that threshold and more.