The two drugs treat migraines in different ways. Sumatriptan stimulates serotonin receptors, constricting blood vessels to provide migraine relief, while naproxen is a non-steroidal anti-inflammatory drug. In addition to their varying approaches to attacking migraines, the two drugs may be absorbed by the body at different rates when jointly administered. This sort of combination therapy is common in treating cancer, and it's a good idea.
A recent paper in the Journal of the American Medical Association (JAMA) presented results from two phase 3 studies of Trexima, which Pozen is developing in partnership with GlaxoSmithKline
For me, this study leaves a pretty big unanswered question: What is the benefit of a single pill combining two existing drugs, compared to just taking each drug separately?
I did some more digging and discovered a paper published in 2005, which found that the combination of the two drugs was superior to either given alone.
With clear benefits to Trexima, it will be interesting to see whether Pozen can get the FDA's thumbs-up. The company has a dubious track record at getting such combination drugs approved; it recently settled a shareholder lawsuit arising from previous failures to do so.
Both of these drugs are well-known, so approval is likely, though not assured. But I'm also wondering whether insurance companies will foot the bill for Trexima. At the end of the day, sales are all that matter. With naproxen already available as a cheap generic, and sumatriptan soon to follow, convincing patients to pay more for a single pill may be tough.
If Trexima's not approved, Pozen's stock will clearly tank. Any benefits stemming from the drug's successful approval are harder to gauge. The stock price could get a bump up, or it could slump as investors betting on approval sell to lock in gains. In the long term, Trexima's sales will drive Pozen's share price. I don't think the prognosis looks good for either one.