Roughly 40% of the cost of 6 months of onabotulinumtoxinA for the treatment of chronic migraine is offset by resultant decreased use of emergency departments, urgent care facilities, and migraine-related hospitalizations, according to a prospective, real-world, cost-benefit study conducted in clinical practice.

“The associated savings offset a reasonable proportion of the cost of treatment for the entire group – nonresponders as well as responders – and there were a fair number of nonresponders because this was a severely affected group,” Dr. John F. Rothrock said at the European Headache and Migraine Trust International Congress.

Dr. John F. Rothrock

Moreover, the 40% figure undoubtedly underestimates the total savings by a considerable margin because it includes only migraine-related direct medical costs for emergency department and urgent care visits and hospitalizations. Additional savings would be expected as a result of reduced need for abortive medications and prophylactic therapies, as well as decreased work absenteeism, which is a “gigantic” indirect cost associated with chronic migraine, noted Dr. Rothrock, professor and chief of neurosciences at the University of Nevada, Reno.

Chronic migraine, defined as migraine headaches an average of at least 15 days per month, affects 1%-2% of U.S. adults. The costs, both economic and in terms of diminished quality of life, are enormous. Botox is the only Food and Drug Administration (FDA)-approved therapy for this common disorder.

But onabotulinumtoxinA (Botox) is also an expensive therapy, and that’s what prompted Dr. Rothrock to systematically study the treatment’s real-world economic impact.

He reported on 230 consecutive chronic migraine patients treated with Botox using the same protocol as in the two pivotal PREEMPT (Phase III Research Evaluating Migraine Prophylaxis Therapy) studies (Cephalalgia 2010;30:793-803 and 804-14) that led to FDA approval of an indication for Botox in treating chronic migraine: namely, injections at baseline, 3 months, and 6 months.

Nearly three-quarters of participants in Dr. Rothrock’s study were rated as having “very severe disability” using the MIDAS (Migraine Disability Assessment Score) system. The majority of patients had a median 36-month history of daily or near-daily headache. Subjects had tried a median of three appropriately dosed prophylactic agents before they received Botox. Thirty-seven percent of participants had symptomatic headache medication overuse.

Forty-eight percent of patients had a positive treatment response to Botox as defined by at least a 50% reduction in the number of headache days per month during month 6, compared with the month prior to starting treatment. In other words, they were successfully converted from chronic to episodic migraine.

The cost of a Botox treatment session, including the drug and reimbursement for the procedure, was estimated at $1,300. Costs for emergency department visits and other end points were based upon national averages.

The reduction in direct medical costs in the overall group during the 6 months after starting Botox was a mean $1,025, compared with the 6 months prior to beginning therapy. This was driven mainly by a mean 0.92 fewer emergency department visits and 0.39 fewer urgent care visits.

Asked when he typically resorts to Botox in patients with migraine, Dr. Rothrock replied that while many physicians reserve it for end-of-the-line therapy, as an advocate of evidence-based medicine, he disagrees with that approach.

“There’s clear evidence that Botox works. It’s the only FDA-approved treatment in the United States for chronic migraine, period,” said Dr. Rothrock, who is the editor-in-chief of the journal Headache.

“But I think if you look at the literature concerning topiramate you’ll find that topiramate owns a pretty good evidence base,” the neurologist continued. “My approach to the chronic migraine patient who’s topiramate naïve, which is a rare thing, is to try topiramate first. And if they tolerate it well, which is often a problem, and they respond well, then that’s great. I do that for cost reasons. It’s a lot cheaper than beginning Botox. But if they don’t respond to topiramate or they can’t tolerate it and they can’t then try zonisamide, a molecularly similar drug that has a middling-weak evidence base, then I’ll go straight to Botox. It’s my second-line therapy.”

Aside from topiramate, the myriad other drugs used off-label for prophylaxis of chronic migraine have virtually no supporting evidence for that application, Dr. Rothrock observed.

“And I would maintain that the longer the patient remains in chronic migraine, the tougher will be your job to get them out of chronic migraine. So we can fiddle around with verapamil, et cetera, for chronic migraine, but I really would urge you to consider putting Botox very close to the top of your treatment armamentarium,” he concluded.

The study was supported by a grant from Allergan. Dr. Rothrock reported serving as a consultant to the company