Did You Quit Your CGRP Preventative Too Soon?
Typically, it seems to be a good idea to try any new treatment for three months. But a new study from Italy is suggesting that some patients may be quitting certain treatments too soon.
In this case, we’re talking about CGRP inhibitors that are used as migraine preventatives.
The study was presented at last month’s annual American Headache Society meeting. The study followed patients who were taking anti-CGRP medication for 48 weeks (about 11 months). The overwhelming majority of patients did indeed respond to the medication within 12 weeks. But depending on the medication, between 7.6% and 15.5% responded in weeks 13-48, the median time of response for the “late responders” being 20 weeks, or about 4.5 months.
Studies like this, though preliminary, raise some interesting issues. Dr. Deborah Friedman (from the University of Texas Southwestern Medical Center), quoted in an article in Neurology Today, gives her response to some of the online chatter that’s been happening:
There are colleagues of mine who said anybody who would keep somebody on a medication that didn’t work longer than three months, it’s unethical. Well, I keep my patients on it for four to six months and that’s what we did with Botox, because I’ve seen people respond late.
Dr. Deborah Friedman
Unethical? Why unethical?
Think about it. Even if there are a few people who may respond late, your chances of responding to the medication do significantly drop after 12 weeks. So if every patient is now put on a trial of 20 weeks or more (some are suggesting 6 months to a year), the drug company selling the product certainly benefits. The insurance company may not be so sure. And most of the people taking the medication for those extra weeks will never benefit from it, and so are only dealing with any side effects with no benefit at all. That’s the cold number crunching.
But the fact remains that some patients may be missing out because they’re only trying the medication for 12 weeks.
All right then, is there a way we could identify those patients – the ones that will benefit eventually – thus improving the odds?
The study has perhaps started to point the way. The researchers did note some tendencies among the late responders:
- More likely to have a higher average body mass index
- Slightly less likely to have one-sided pain with allodynia (more on this below)
Of course, this works both ways. If you have one-sided pain with allodynia, you may be a little more likely to benefit from an anti-CGRP preventative. Because basically the late responders were simply a little more like the non-responders.
This is a long way from a way to identify which patients will respond late. But what the study does tell us is that we should be looking closer to find out how we can identify those patients – it shows us that there may be a way, eventually.
Right now, it’s probably best to have a good relationship with a specialist you trust, and let them help you decide if it’s worth it to try your medication (or other treatment) for longer. They know you best, and know your medical history.
To delve further into this topic, check out the article at Neurology Today by Thomas R. Collins: Late Migraine Responses Seen for Anti-CGRP Therapy
Also the National Headache Foundation has put out a video on the optimistic side, explaining this study:
You can read more about the history of this drug, along with more useful information, in the press release from Teva: