The first of the four CGRP monoclonal antibodies developed for the prevention of migraines is expected to be approved by the FDA in the next 2-3 months. The other three should be approved within a year. All four will be given by an injection (three subcutaneously and one, intravenously).
Most people prefer tablets to injections and two companies are developing three drugs with the same mechanism of action as the monoclonal antibodies (blocking CGRP), but in a tablet form. The original CGRP drug in a tablet form was developed by Merck and it was very effective for the prevention and acute treatment of migraines, but a few patients developed liver side effects. The side effects were not serious, just abnormal blood tests, which returned to normal once the drug was stopped, but nevertheless Merck stopped the development of telcagepant in 2009. This led pharma companies to shift to the development of monoclonal antibodies, which bypass the liver, but can be given only by injection.
Allergan and Biohaven are two companies that are developing oral CGRP drugs in the hope that they can achieve good efficacy without the side effects. Allergan just released the results of the first phase 3 study of ubrogepant. The study included 1327 U.S. adult patients who were given placebo, ubrogepant 50 mg or 100 mg. They treated a single migraine attack of moderate to severe headache intensity. Both doses were significantly better than placebo in achieving pain freedom at 2 hours after the initial dose. Sensitivity to light, noise, and nausea also significantly improved with the drug, but not placebo. The side effect profile of ubrogepant was similar to placebo without serious liver problems.
Results of the second phase 3 trial are expected in the first half of 2018. Allergan plans to file these results with the FDA in 2019, after which the FDA has a year to review the data and will hopefully approve the drug.
