Tosymra is a product that uses a novel way to deliver sumatriptan through the nasal passages. Unlike other nasal formulations of sumatriptan, Tosymra uses proprietary technology, Intravail, which enhances the absorption of sumatriptan through the nasal mucosa. This allows a dose of 10 mg to achieve similar blood level to that of a 4 mg injection of sumatriptan. Clinical trials have confirmed high efficacy of Tosymra in migraine patients.
Many migraine sufferers experience nausea, which makes oral medications ineffective they take too long to work. Sumatriptan injections can be very effective, but many patients are reluctant to use them and they tend to cause more side effects. Nasal delivery offers a good middle road – better and faster delivery than by mouth without the pain and side effects of an injection.
The regular liquid sumatriptan nasal spray (Imitrex NS) has been on the market for a couple of decades, but it has never become a popular product. This is partly due to the fact that it is not consistently or well absorbed. The spray contains 20 mg of sumatriptan delivered through a relatively large droplets of fluid. Some of it is drips out from the nose, while some is swallowed and gives an already nauseated migraine patient a bad taste in the mouth.
Another formulation of nasal sumatriptan was Onzetra, which delivered powdered sumatriptan through an ingenious device. It required the patient to blow the powder into the nose and it appeared to have good efficacy. However, it was somewhat cumbersome to use, very expensive (up to $100 a dose) and because of that it never caught on. Onzetra is no longer being sold.
I think that Tosymra is going to be a very useful addition to our lineup of abortive migraine drugs, provided it is reasonably priced and is covered by insurance companies.
