By Vrinda Manocha
(Reuters) - Biotechnology company United Therapeutics Corp said the oral version of its drug to treat hypertension was rejected for the second time by health regulators, sending its shares down as much as 7 percent in morning trade on the Nasdaq.
The drugmaker had resubmitted its marketing approval application last month, and an analyst said the fresh rejection was likely to necessitate new trials and a delay of about four years before the company tried again.
The drug, treprostinil diolamine, was first rejected by the Food and Drug Administration (FDA) in October after it had failed to show statistically significant results in patients taking a six-minute walk test during clinical studies.
The company would now probably conduct another late-stage trial for the drug as it had originally planned, Wedbush analyst Liana Moussatos told Reuters. After the first rejection, the company had said that it could take four years to conduct a new trial and make a new application, she said.
However, "they did some additional analysis and brought in some historical data and thought they would give it another shot," she added.
United Therapeutics already has a treprostinil injection named Remodulin and an orally inhaled version Tyvaso on the market to treat pulmonary arterial hypertension (PAH), a disease characterized by abnormally high blood pressure in the pulmonary artery that carries blood from the heart to the lungs.
The FDA's latest rejection letter did not contain any new issues, the company's vice president for business development, Martin Auster, told Reuters.
"Our infused and inhaled versions have only penetrated a fraction of the market," Auster said. "We believe an orally delivered offering would be preferred by patients and physicians."
Wedbush's Moussatos said United Therapeutics did not need oral treprostinil to maintain its growth. She had earlier projected $399 million in peak annual sales for the drug, but had not included the oral variant in her model.
Remodulin, the company's lead product, accounted for $458 million in revenue last year, about half of United Therapeutics's net revenue. The company also sells Adcirca, an oral tablet to treat PAH.
United Therapeutics' PAH drugs compete with Gilead Sciences Inc's Letairis, Pfizer's Revatio and Swiss biotechnology company Actelion Ltd's Tracleer and Veletri.
United Therapeutics shares, which have risen about 14 percent since the drug was first rejected last year, were down about 2 percent at $59.73 on the Nasdaq.
(Reporting By Vrinda Manocha in Bangalore; Editing by Sreejiraj Eluvangal)