FDA extends action date for inhaled Treprostinil (Tyvaso) NDA by three months

United Therapeutics Corporation has announced that the U.S. Food and Drug Administration (FDA) will require additional time to complete its review of the New Drug Application (NDA) for Tyvaso (inhaled treprostinil).

In a notice received today, the FDA extended the Prescription Drug User Fee Act (PDUFA) date from April 30, 2009, to July 30, 2009. United Therapeutics previously disclosed the likelihood of this delay in a press release dated March 16, 2009.

The three-month extension was triggered by United Therapeutics' April 2009 submission to the FDA of the results of a human factors study, which was considered a major amendment to the NDA. In March 2009, the FDA notified United Therapeutics that it required human factors testing to validate the instructions for use of the Optineb(R) nebulizer in order to complete its evaluation of the Tyvaso NDA. "We look forward to working with the FDA as it completes its review of our human factors study submission," said Roger Jeffs, Ph.D., United Therapeutics' President and Chief Operating Officer. "We made every effort to conduct and submit the study as quickly as possible."

"We are most appreciative of the FDA's input as we work toward our goal of bringing Tyvaso to market," said Martine Rothblatt, Ph.D., United Therapeutics' Chairman and Chief Executive Officer. "This news will provide considerable hope to the thousands of pulmonary hypertension patients struggling with existing treatments."