Actelion’s Lung Drug May Face Study Against Gilead Rival

Actelion Ltd.’s Opsumit may face a clinical trial comparing its effectiveness with Gilead Sciences Inc.’s lung drug Letairis, potentially threatening the treatment’s predicted dominance.

A so-called head-to-head study is “something we have to consider that might be an important next study for us,” Gilead Chief Operating Officer John Milligan said yesterday in an interview at Bloomberg News in New York. He said the Foster City, California-based company has no concrete plans yet for such a trial. Actelion shares fell 1.9 percent.

Actelion won approval in the U.S. and Europe last year for Opsumit as a treatment for pulmonary arterial hypertension, a rare and deadly lung disease, after a 742-patient trial showed that those who took the drug were 45 percent less likely to get sicker than those given a placebo. Actelion has said that a head-to-head trial comparing its product with Gilead’s Letairis would require more than 5,000 patients to show a statistically significant difference, making it impractical.

Head-to-head studies “can be very valuable, if you win,” Milligan said. “We have been willing to do head-to-head studies historically. If you don’t have the courage of your convictions that your drug is better than the other company’s drugs, then really, why are you developing it?”

Shares Decline

Actelion shares dropped to 88.30 Swiss francs in Zurich, giving the company a market value of 10.6 billion francs ($11.8 billion).

Gilead, the world’s biggest biotechnology company by market value, has more to gain and less to lose than Actelion from such a trial. A study that found Opsumit superior would cement the Allschwil, Switzerland-based company’s dominance in the area, while jeopardizing a drug that accounts for less than 5 percent of Gilead’s sales. The opposite result would undermine a product that analysts predict will account for almost half of Actelion’s revenue by 2017.

Still, the size and duration of a trial needed to show a difference between the two products may make it impractical for Gilead, given its patent on Letairis will expire by 2018, Guillaume Van Renterghem, an analyst at UBS AG in London, wrote in a note today.

“Although running such a study carries some theoretical risk to Opsumit, we believe it does not make financial sense for Gilead,” Van Renterghem wrote. “We believe they would be able to show, at best, a non-inferior efficacy, hence not providing them enough marketing argument to justify the cost of such a large trial.”

Roland Haefeli, a spokesman for Actelion, declined to comment.

Takeover Rebuff

Opsumit is designed as a successor for Tracleer, which accounted for almost 90 percent of Actelion’s sales last year and will start losing patent protection in November 2015. Tracleer has been ceding market share to Letairis since the U.S. Food and Drug Administration allowed Gilead to remove a reference to the risk of liver damage from the drug’s label in

2011. When the FDA approved Opsumit, it said the drug also won’t have to carry that warning.

Actelion’s co-founder and Chief Executive Officer Jean-Paul Clozel cited Opsumit’s sales potential as a reason for the company to stay independent when Amgen Inc. in 2010 considered making a takeover offer. He reiterated that position in 2011 when fighting off a hedge fund that sought seats on the board and urged Actelion to consider selling itself.

Drug’s Weaknesses

Gilead also wants to see what experience doctors and patients have with Opsumit, which would help design a study to uncover some of the drug’s weaknesses, Milligan said.

“I’ve heard anecdotally some good stories and some bad stories about Opsumit, but I don’t know where the truth lies yet,” Milligan said.

Pulmonary arterial hypertension is a deadly disease in which the arteries that carry blood from the heart to the lungs narrow, making the heart work harder and causing elevated blood pressure. That causes symptoms such as chest pain, dizziness and shortness of breath. There is no cure. The disease affects from 1 in 100,000 people to 1 in 1 million people, according to the American Lung Association.