BioWorld International Correspondent

LONDON - Vernalis plc announced positive results in the confirmatory Phase III study of its migraine treatment Frova in treating menstrual migraine, opening the door to a new drug application filing in the next few weeks and a $40 million milestone payment from its U.S. partner, Endo Pharmaceutical Holdings Inc.

If approved, Frova would become the first triptan registered in the U.S. for menstrual migraines, where 12 million women are affected. The drug already is approved for the treatment of acute migraine.

Apart from triggering a $40 million milestone payment from Chadds Ford, Pa.-based Endo, approval will mean Vernalis receives a higher royalty rate of 20 percent, rising to 30 percent depending on the level of sales.

Simon Sturge, CEO, said the positive results "are a further demonstration of Vernalis' ability to deliver on expectation."

Sturge told an analysts' meeting that the key distinguishing feature of Frova is its long half-life of 26 hours. That compares to two to six hours for other marketed triptans.

"That's why it is so good for treating migraines of long duration like menstrual migraines," he said. Typically, menstrual migraines are more severe, last longer and are less responsive to treatment than other types.

The trial involved women who had not responded to non-triptan or other triptan treatments. "In other words, they were difficult to treat, and some were so badly affected they were taking anti-convulsants, opiates and barbiturates," Sturge said.

The 427 patients were randomized to receive either placebo, or once or twice-daily dosing with Frova. Both Frova doses demonstrated efficacy in the primary endpoint of the number of migraine-free periods and achieved statistical significance in other measures of effectiveness, including the use of rescue medication. "The data are outstanding," Sturge said.

Not all 12 million U.S. sufferers of menstrual migraine are diagnosed, and some respond to other therapies, but there likely is a significant market. "This is a huge opportunity for Vernalis," Sturge said. "The fact the data are positive reduces the risk we don't get the $40 million [milestone payment] and gives us the potential of the drug - no matter how big you think the market is."

The trial results also open up a greater potential market in Europe. "For example, Frova is yet to get pricing approval in France and could get it on the back of these data, with France being the second largest market in Europe," Sturge said.

He added: "There is now security within the company. This gives us a strong platform on which to continue to build the business and build on news flow."

Guildford, UK-based Vernalis is expecting to announce progress with a number of other development programs this year, including two Parkinson's disease treatments, the completion of a Phase IIa stroke trial and an HSP90 program moving into the clinic.