Experimental Drug May Fight Migraine

MK-0974 could aid patients not helped by other medicines.

By Randy Dotinga
HealthDay Reporter
Thursday, June 7, 2007; 12:00 AM

Copyright © 2007 ScoutNews, LLC. All rights reserved.

THURSDAY, June 7 (HealthDay News) - A new drug to rescue migraine patients who aren't helped by standard medications shows promise, early findings suggest.

Doctors caution that the newly released findings, from an ongoing research project funded by a drug company, aren't the final word on the experimental medication, called MK-0974. But the initial results provide some reason for hope, said the study's co-author, Dr. Alan Rapoport, a neurologist at the University of California at Los Angeles.

At issue are the estimated 28 million Americans who suffer from migraine headaches. Doctors successfully treat many of them with ordinary painkillers and other approaches such as biofeedback; others receive newer drugs known as triptans that relieve swelling in the brain.

But for some migraine patients, the pain is inescapable no matter what drug they take. Certain patients can't take triptans because they constrict blood vessels -- a no-no for those with heart conditions.

Unlike triptans, MK-0974 is part of a new class of drugs known as calcitonin gene-related peptide (CGRP) receptor antagonists. These agents block a brain chemical that helps send pain signals.

The researchers were scheduled to release the findings of the phase II study Thursday at the annual meeting of the American Headache Society in Chicago.

Drugs typically go through three phases of testing, with the second phase devoted to figuring out the most effective dosage level. A phase III trial -- designed to actually tell doctors how well the drug actually works -- is now in progress for MK-0974.

In the new research funded by Merck, the manufacturer of the drug, 68 percent of those who took a 300 mg. dose reported pain relief two hours later. That rate was almost identical to the 70 percent of people who took a triptan called rizatriptan. Of those who took a placebo, 46 percent reported relief.

After 24 hours, almost 40 percent of those who took the new drug reported being free of pain, compared to 18 percent of those who took the triptan and 11 percent of those who took the placebo.