Phase II clinical trials of a series of drugs that target calcitonin gene-related peptide (CGRP) have brought another round of promising results, which were presented at the American Headache Society’s scientific meeting in June. Four drugs are currently in development and three reported results at the AHS meeting. Those three drugs have all successfully reduced the number of migraine attacks in study participants—and one began working in only a week. These drugs "clearly work for a substantial proportion of people," Peter Goadsby, M.D., one of the researchers working on drug development, said. "About half of patients will get 50 percent response, and a fifth will get 100 percent response."

These drugs work by attaching to a protein, called CGRP, that helps the brain and immune system to communicate with each other and transmits pain signals during migraine attacks. When CGRP is released by nerves, it causes inflammation in the nervous system. Triptans also work on CGRP, but they are acute treatment for a migraine attack already in progress, while the new drugs aim to prevent the attack from occurring in the first place.

Results presented at the AHS meeting, identified by the experimental name for each drug:

• TEV48125: More than half the patients experienced a 50% or greater reduction in migraine frequency. Many experienced a reduction in frequency after only one week.
• AMG 334: Reduced the number of migraine days by 50% in about half of patients after 12 weeks.
• LY48125: showed the drug prevented migraine attacks more effectively than a placebo.

Instead of a daily pill, the drugs are delivered by injection once a month. It is still uncertain whether patients will be able to administer the drugs themselves or if they’ll need to go to their doctors office for the injection.

Thus far, the drugs appear to be safe with few side effects. If these drugs come to market, they will be the first preventive drugs ever developed for migraine. 

REFERENCES

American Headache Society press release. Migraine Community Sees Promise in New Class of Drugs; Optimistic for Relief for Millions of Sufferers. June 17, 2015. Retrieved on July 17, 2015 from https://bit.ly/3X7psFf

American Migraine Foundation (2015). Once-a-Month Injections for Migraine? Retrieved on July 17, 2015 from http://www.americanmigrainefoundation.org/resources-and-links/once-a-month-injections-for-migraine/

WebMD (2015). New Drugs May Prevent Migraines Before They Start. Retrieved on July 17, 2015 from http://www.webmd.com/migraines-headaches/news/20150618/new-drugs-might-prevent-migraines-before-they-start