Promising Migraine Preventive Drugs Target CGRP
Positive findings from two phase II clinical trials of promising migraine preventive medications were announced today (here’s the full press release). If these drugs make it to market, they’ll be the first developed specifically for migraine prevention.
These drugs are the first to test monoclonal antibodies for migraine prevention and both target the protein calcitonin gene-related peptide (CGRP). If those words are gibberish to you, here’s a brief introduction to CGRP and its role in migraine from James at Headache and Migraine News. (I intend to write an explanation at some point, but don’t currently have the mental ability.)
The first study included 163 people who had five to 14 days of migraine attacks each month. They either received a single IV dose of the drug, called ALD403, or a placebo*. After 24 weeks, those who received the drug had an average of 5.6 fewer migraine days a month (a 66% reduction) than before receiving the dose and 16% were migraine-free after 12 weeks. Those who received the placebo had 4.6 fewer days per month (a 52% decrease) and none were migraine-free. Side effects were the same for both groups.
The second study included 217 people who had migraine from four to 14 days per month. For 12 weeks, participants received biweekly injections of the drug, LY2951742, or a placebo. After 12 weeks, those who received the drug had an average of 4.2 fewer migraine days a month (a 63% decrease), while those who received the placebo had 3 fewer migraine days a month (a 42% reduction). Participants who received the drug were more likely to have side effects than those who received the placebo. These side effects included pain at the injection site, upper respiratory tract infections and abdominal pain. Still, the drug was considered overall to be safe and well-tolerated.
Those are definitely good early results. More, larger studies are needed to confirm the findings.
Even more than the results, I’m struck by the positive, hopeful comments from two researchers involved in the studies, both highly regarded in the field:
“These results may potentially represent a new era in preventive therapy for migraine.” –Peter Goadsby, MD, PhD, UC San Francisco
“We’re cautiously optimistic that a new era of mechanism-based migraine prevention is beginning.” –David Dodick, MD, Mayo Clinic Arizona
While not effusive, these comments echo the optimistic, hopeful attitude I’ve heard countless headache specialists use when talking about CGRP drugs. I, too, am quite hopeful for these drugs.
*The placebo effect is way oversimplified as the power of positive thinking. The process is far more intricate that “you think it will work, so it does.” It’s another topic I’m planning a post on, but I don’t know when I’ll get to it. If you’re curious to learn more, Jerome Groopman’s book The Anatomy of Hope describes it well, and Placebo Effect Stronger Than We Thought? is a good article.