FDA: Oral Treprostinil for PAH Rejected Again

Shelley Wood

March 25, 2013

The US Food and Drug Administration (FDA) has, for the second time, rejected the oral tablet version of a drug approved more than a decade ago for the treatment of pulmonary arterial hypertension (PAH). Treprostinil is already available as an injectable drug (Remodulin), and in an oral inhaled version (Tyvaso), made by the same company, United Therapeutics.

The company announced it had received a complete response letter from the FDA, declining to approve treprostinil diolamine extended-release tablets.

The agency had previously turned away the oral form of the drug back in October, following the release of a small company-sponsored trial, FREEDOM-C, showing that patients who took oral treprostinil on top of other PAH drugs had no improvement in their 6-minute-walk test, compared with PAH patients taking placebo.

Since then, however, another second small trial, FREEDOM-M, again funded by United Therapeutics, showed that 151 newly diagnosed PAH patients randomly assigned to treprostinil monotherapy over 12 weeks fared better on a 6-minute-walk test than 77 patients randomly assigned to placebo.

A press release issued today quotes company chair and CEO Martine Rothblatt saying, "We remain confident that oral treprostinil will play an important role in treating PAH, and we are committed to working collaboratively with the FDA to accomplish this goal in the most timely and appropriate manner."