Allergan's "Eye-popping" Migraine Botox Study: Freedom of Expression or Off-Label Promo Tool?

"A preliminary study suggests the same type of botulinum injection used for cosmetic purposes -- Botox -- may be associated with reduced frequency of migraine headaches that are described as crushing, vicelike or eye-popping (ocular), but not pain that is experienced as a buildup of pressure inside the head, according to a report in the February issue of Archives of Dermatology, one of the JAMA/Archives journals" (see press release here).

This caught my attention because (1) this study was supported in part by a grant from Allergan Inc., the company that markets Botox, (2) co-author Dr. Burstein serves as a consultant to Allergan Inc. and receives honoraria for lectures and grants for clinical and animal research, and (3) the authors admit how difficult it is to demonstrate that Botox is more effective than placebo for treatment of migraine headaches.

Regarding the latter point, the authors write: “The initial promise of a new prophylactic [preventive] therapy for migraines was met by the challenge of replication of these results,” as subsequent studies have failed to demonstrate botulinum was more effective than placebo.

Sounds like the end of the road for Botox as a treatment for migraine. But wait! The authors acknowledge that “researchers have searched for patient characteristics that may predict a favorable treatment response.” In other words, let's find some migraine patients for whom Botox works.

According to this study, Botox may be effective in the treatment of "imploding" or "eye-popping" headaches but NOT "exploding" headaches. Among all participants who responded to treatment, patients with exploding headaches experienced an average reduction in migraine frequency of 11.4 to 9.4 days per month (ie, not much improvement), whereas frequency in participants with imploding or ocular headaches reduced from an average of 7.1 days per month to 0.6 days per month.

“These preliminary data are intriguing, and our results provide support for the hypothesis that patients with migraine that is characterized by imploding and ocular headaches are more responsive to botulinum toxin type A than those with migraine characterized by exploding headaches,” the authors write. “Our findings invite consideration of using botulinum toxin type A injections to prevent migraine headaches and may promote the role of the dermatologist in the treatment of patients with migraine. However, well-controlled trials need to be conducted to confirm these findings.”

The article estimates that 28 million Americans suffer from migraine headaches. It does not specify how many suffer "imploding" vs "exploding" headaches. It does say that 10 of the 18 patients studied experienced the former type. From that, one might assume that 15-16 million Americans suffering from migraines could be helped by Botox -- AND smooth out those wrinkles at the same time!

I am sure that Allergan will be packaging reprints of this study to hand out to physicians even though Botox is not approved for the treatment of migraines. The Allergan reps may even use my faulty analysis to claim that there are 15-16 million potential migraine patients out there that dermatologists can tap into.

New FDA guidelines permit this kind of off-label promotion -- I mean "freedom of speech," also known as "freedom of expression" in Botox ads like the one on the left, which I modified to show how it might look after FDA approves Botox for "eye-popping" migraine relief.

Allergan is the the drug industry poster boy for off-label promotion; it is currently suing the FDA "seeking a ruling that would allow [it] to proactively share truthful and relevant information with the medical community to assist physicians in evaluating the risks and benefits of BOTOX" (see press release).