Pozen Inc. could garner up to at least $160 million after entering a deal with GlaxoSmithKline plc surrounding a migraine treatment.

The Chapel Hill, N.C.-based firm has developed a combination drug technology called MT 400, which couples a marketed triptan with a long-acting, nonsteroidal, anti-inflammatory compound. Phase II studies have borne out MT 400's effectiveness, and the partners plan to further develop combinations of triptans (5-HT1B/1D agonists) with the NSAID.

"The product's benefits include a faster onset of action. Many more patients will respond because there are two real different mechanisms of action and we've significantly enhanced the time of response," John Plachetka, Pozen's chairman, president and CEO, told BioWorld Today. "We have taken a two-hour product and made it last 19 hours."

He added that the use of MT 400 produces no additional side effects to those seen with its components when used individually. Plachetka also noted that London-based GlaxoSmithKline, which houses operations in the Research Triangle Park area as well, was a logical partner given its introduction of the triptan class, with research dating to the 1970s.

"They pioneered this and really established themselves as the No. 1 migraine company in the world, both from a research base and also a commercial base," Plachetka said. "They have more strength and experience with migraine doctors than any other company, so you couldn't find a better partner."

GlaxoSmithKline's triptans include Imitrex (sumatriptan, sumatriptan succinate) and Amerge (naratriptan hydrochloride). Plachetka said he worked at Glaxo on the development of the injectable product Imitrex earlier in his career.

Pozen will receive an up-front fee and initial milestone payment of $25 million later this year, with potential milestones worth an additional $55 million over the next several years as development continues up to the point of regulatory filings and approvals. GlaxoSmithKline retains exclusive U.S. marketing and commercialization rights to any combination that uses one of its currently marketed triptans and the NSAID, for which it would pay sales performance milestones that could reach $80 million, as well as undisclosed royalties.

The companies expect to begin Phase III trials next year, with Imitrex as the triptan part of the combination.

Pozen, a 27-person company that reported a cash position of $46 million as of March 31, owns two U.S. patents related to the combination technology and was issued a notice of allowance for another.

Its stock (NASDAQ:POZN) surged on the news Thursday, gaining $2.33, or 30.3 percent, to close at $10.03.

GlaxoSmithKline also will provide formulation development and manufacturing, while Pozen will be responsible for all other clinical development. The company said such expenses would not impact its burn rate the rest of the year.

Phase II data from a trial involving 972 patients showed that MT 400, using a marketed triptan and an NSAID, provided a more than 50 percent improvement in sustained pain relief over triptan alone, with a similar side effect profile. The combination provided a 46 percent improvement, while monotherapy resulted in a 26 percent improvement and placebo patients improved by 17 percent.

During a conference call, Plachetka noted the therapeutic gain endpoint was 29 points higher for the combination therapy.

"When we went to the FDA at our end-of-Phase II conference, they were equally impressed with this benefit," he said, adding that the agency said Pozen could move into a Phase III program based on the findings.

But before beginning any more clinical work, Pozen will wait on clinical batches of material from its partner. And both will hash out trial protocol plans through a joint committee, though Plachetka said the program would most likely include more than one trial.

Clinical development of migraine products is nothing new for Pozen, which has two later-stage products that could operate in the same worldwide market.

Late last year the company filed a new drug application for MT 300, its injectable formulation of dihydroergotamine mesylate dosed through a prefilled syringe, for severe migraine sufferers. (See BioWorld Today, Dec. 18, 2002.)

And later this summer, Plachetka said Pozen expects to file for FDA approval of MT 100, an oral product designed to treat mild to moderate migraines. The company already has filed for approval in the UK.

While MT 300 is more of a niche product, Plachetka said MT 100 represents a "fantastic product opportunity." But Pozen has yet to find a partner for the product, in part because of carcinogenicity issues. A rat study is under way, and the company's FDA submission will be made on a rolling basis as clinical work is complete.

"Finding a partner for MT 100 has been hampered somewhat by the carcinogenicity data that is coming available in the next few months," he said. "As soon as those data are available, I think everyone's questions will be satisfied."

With MT 400 now partnered out, he said Pozen would shift more attention back to the other products. And, Plachetka said Pozen would introduce a nonmigraine product later this year.

"You're going to continue to see a lot of very positive news flow from Pozen," he added. "These are good products that will establish a lot of positive cash flow to fuel our growth."