Breakthrough in the treatment of migraines

Two landmark studies on an entirely new type of treatment for migraines have been just published in the New England Journal of Medicine.

One of the reports describes a phase 3 trial (final phase that can lead to the FDA approval), which was conducted by Teva Pharmaceuticals using a monoclonal antibody, fremanezumab to treat patients with chronic migraine (patients with 15 or more headache days each month). The study involved 1,130 patients who were divided into three groups: one group received monthly injections (subcutaneously, i.e. under the skin) of the active medicine, another group was given an injection of the real medicine every 3 months and placebo injections monthly in between, and the third group received placebo injections every month. Patients in both groups that received real shots did much better than those given placebo. They had fewer days with headaches, used less of the abortive migraine medications, and had a lower impact of migraines on their lives. The effect of the drug lasted 3 months, which suggests that one injection every three months will be sufficient. We also hope that patients will be able to inject themselves and not have to come to doctors’ offices every month. The side effects were mostly related to the injection itself – pain, swelling, and bruising.

The second study conducted by Amgen and Novartis utilized a similar drug, erenumab (it will have the brand name of Aimovig when it becomes available in the middle of next year) to prevent episodic migraines, that is migraines that occur on fewer than 15 headache days each month. A total of 955 patients participated in this study and they were also divided into three groups: those receiving either 70 or 140 mg of medicine and a group receiving placebo. Injections were given monthly to prevent migraine attacks. Both doses of the drug resulted in significantly fewer migraine attacks and improvement in physical impairment and everyday activities. Side effects were mostly due to the injection site reactions, just like with fremanezumab.

Both fremanezumab and erenumab belong to the family of CGRP monoclonal antibodies, drugs that block a neurotransmitter CGRP which is released during a migraine attack. Two additional companies, Eli Lilly and Alder are developing similar drugs, galcanezumab and eptinezumab, which are also expected to be approved next year. Eli Lilly’s drug is also being tested for the prevention of episodic cluster headaches.

I first wrote about the CGRP drugs in a blog post in 2007, more than 10 years ago. At that point CGRP was the target of research for over 10 years, so in total, it will have taken 20 years to bring these new drugs to the market. It was even longer with triptans, such as sumatriptan (Imitrex) – it took 30 years since the discovery of the potential role of serotonin to the approval of sumatriptan. The drug development process takes not only decades of time, but also billions of dollars, which explains why new drugs are so expensive, at least in the first few years. After years of being on the market, prices of drugs tend to go down and now 90 tablets of sumatriptan can be bought for $70 at Costco, while similar branded triptan drugs used to cost $40 for a single tablet.