Vernalis shares plunge on FDA rejection

The decision means a delay to a milestone payment Vernalis is due from US partner Endo Pharmaceuticals. The $40 million payment triggered by an approval would have gone some way to paying down the company's debt of $50 million to Endo.

The FDA has identified deficiencies and asked for additional information pertaining to Endo's supplemental new drug application (sNDA) for Frova (frovatriptan succinate) 2.5mg tablets in a “not approvable” letter, according to the company. Frova is already approved for the treatment of migraine with or without aura in adults where a clear diagnosis of migraine has been established.

While the FDA acknowledged that both pivotal efficacy trials that had been submitted as part of this sNDA met their primary endpoints in significantly improving the number of headache-free perimenstrual periods, it questioned whether the benefit demonstrated was clinically meaningful. The FDA also noted that even though serious vascular adverse events were not observed in this drug development program, an increased risk (compared to the approved acute use) could not be ruled out.

Simon Sturge, CEO of Vernalis, said: “We are surprised and disappointed by the FDA's response, as they had not engaged the companies in any dialogue during the extended review cycle as to FDA's interpretation of the data in the application.”

Vernalis said that it had already been evaluating a number of options for its overall operations, which it would now review in light of the FDA decision.