A promising new migraine drug from Merck is shelved

Merck discontinued the development of telcagepant, a promising new drug which represents a new class of migraine drugs, so-called CGRP antagonists. These drugs appear to be as effective as sumatriptan (Imitrex) and other triptans in aborting a migraine attack, but do not carry an increased risk of strokes and heart attacks which can occur, albeit very rarely, with triptans. Telcagepant was also tested as a daily preventive drug for migraines and in those trials some patients developed minor liver abnormalities. At first, Merck continued to pursue the development of telcagepant for abortive treatment, but recently decided that the risk of not getting it approved by the FDA because of the liver problems was to high. This again demonstrates that part of the reason why new drugs are so expensive – for every one that makes it to the market there are many that after an investment of hundreds of millions of dollars do not. It is likely that Merck and other companies will continue to do research to find a CGRP antagonist without serious side effects.