Second complete response for United's oral treprostinil

FDA issued a complete response letter for a resubmitted NDA from United Therapeutics Corp. (NASDAQ:UTHR) for oral treprostinil to treat pulmonary arterial hypertension (PAH). The company declined to disclose details of the letter, but said the agency did not raise any new issues beyond what was in FDA's first complete response letter for the product. United Therapeutics said it plans to request a meeting with FDA to discuss the letter.

In the first complete response letter in October, FDA questioned the clinical importance of the six-minute walk distance (6MWD) improvement in one Phase III trial of oral treprostinil and the inability to demonstrate a statistically significant effect on 6MWD in two other Phase III trials, as well as the inability to demonstrate an improvement in time to clinical worsening in all three trials (see BioCentury Extra, Oct. 23, 2012). ...