Four companies are testing new drugs that may dramatically reduce the frequency of headaches for people with chronic migraines.

Relief may soon be on the way for people who have chronic migraine headaches.

Similar drugs aimed at preventing the painful headaches are being tested by four pharmaceutical companies, and their early results are promising.

The results are being presented this week at the American Headache Society’s annual meeting in Washington, D.C.

The potential of these new compounds is enormous and gives us real hope that effective specific treatments for migraine may be on the near horizon,” said Dr. Peter J. Goadsby, Ph.D., the chief of the University of California, San Francisco, Headache Center. “The development of CGRP antibodies offers the simple, yet elegant and long awaited option for migraine patients to finally be treated with migraine preventives; it’s a truly landmark development.”

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The four pharmaceutical companies are researching a new class of drugs called calcitonin gene-related peptide (CGRP) monoclonal antibodies. Monoclonal antibodies are so-called “biologic” drugs.

The new drugs work by bringing down levels of CGRP, which transmits pain.

Teva Pharmaceuticals’ experimental drug reportedly reduced the number of headache hours per week for chronic migraine sufferers after a week of use. More than half of the participants saw their headache frequency drop by at least half, the researchers said. In Amgen’s trials, more than half of participants reportedly cut the number of “migraine days” by half after 12 weeks.

Alder Biopharmaceuticals and Lilly researchers also reported successful human trials of new drugs targeting CGRP.

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More than 36 million people in the United States get migraines, according to the Headache Society.

About 4 million have chronic migraines, which means they have more than 15 migraine days a month.

The last breakthrough in migraine treatment was triptans, which were released in 1991. Triptans treat, rather than prevent, migraine attacks.

Goadsby said participants in the trials are being allowed to use both Triptans and the experimental drugs. One to reduce headaches and one to treat them when they occur. So far, he said, no problems have arisen.

“This development is a transformative moment in migraine treatment,” said Goadsby. “There’s no question that we need something better. In fact, for prevention we really need something designed specifically for migraines.”

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