Talk of a possible head-to-head comparison between Actelion’s pulmonary arterial hypertension drug Opsumit and Gilead’s Letairis caused enough of a stir that investors punished Actelion’s stock Tuesday. Bloomberg reports the talk triggered a 3.1% drop in Actelion’s share price, despite the very theoretical nature of the clinical trial.
Bloomberg notes that a trial has varied risks: a Gilead sweep would be bad news for Actelion, which staked its financial independence on Opsumit’s potential, whereas an Actelion win would maybe put a minor dent in a business that accounts for less than 5% of Gilead’s sales. Bloomberg also notes that any Gilead advantage would be short lived, because the Letairis patent expires in four years.
