Allergan Inc. (AGN)’s wrinkle treatment Botox, approved in the U.S. for preventing chronic migraines, provides only modest relief for patients with the headaches, an analysis of previous studies showed.
The study, published today in the Journal of the American Medical Association, found that Botox had no benefit for those with episodic migraines that occur less than 15 times a month, or chronic tension headaches that occur more than 15 times a month. The analysis also showed that Botox reduced chronic migraines and daily headaches by only about two per month.
Botox was approved in the U.S. in October 2010 for chronic migraines, those occurring more than 15 times a month lasting more than four hours each, even though results from studies on the drug’s benefit were mixed, the authors wrote. Today’s findings are the first to assess the available research to show which headaches the treatment helps and which it doesn’t, lead study author Jeffrey Jackson said.
“Botox does appear to have a benefit for people appearing to suffer from chronic migraines and chronic daily headaches,” said Jackson, a professor of medicine at the Medical College of Wisconsin in Milwaukee, in an April 20 telephone interview. “The benefit is only a reduction of two to three headaches a month and that’s in people who have a minimum of 15 headaches a month. So that’s not a large benefit. For people having headaches less than 14 days a month or anyone with a tension headache, it clearly doesn’t work.”
Robert Duarte, director of the Pain Center at the Cushing Neuroscience Institute at North Shore-LIJ Health System in Manhasset, New York, said today’s analysis included studies with different doses of Botox, many lower than the current U.S.- approved dose, which may be why the results show only a slight benefit.
“It still demonstrates that for chronic migraines this is the treatment of choice,” said Duarte, who wasn’t an author on today’s paper, in an April 23 telephone interview. “We have seen clinically that patients’ headaches have been significantly reduced. It is not a cure. It is maintenance therapy. This is the best treatment that we have to date.”
Researchers analyzed 27 studies that looked at Botox versus placebo and four studies that compared Botox to other migraine treatments. Among the trials studying Botox and placebo there were 5,313 total patients, including 1,938 that had episodic migraines, 1,544 who had chronic migraines, 616 who had chronic tension headaches and 1,115 who had chronic daily headaches.
The analysis found that Botox cut the number of chronic migraines per month to 17.2 from 19.5 and reduced chronic daily headaches to 15.4 from 17.5 on average.
$1.59 Billion in Sales
About 50 percent of Botox’s $1.59 billion in 2011 worldwide sales was for therapeutic uses, including chronic migraines, severe underarm sweating and urinary incontinence, according to the Irvine, California-based company’s annual report. Allergan doesn’t break out sales data specific to migraines, said Crystal Muilenburg, a company spokeswoman.
The two additional migraine-free days a month for sufferers using Botox in today’s analysis amounts to 24 days a year, but doesn’t tell the whole story, Muilenburg said. Botox also shortens migraine time in hours and decreases the severity of the headaches, company-funded studies have shown.
“These data reinforce the role Botox plays in the treatment of patients with chronic migraine,” Muilenburg said in a statement. “As the study authors note, their analysis of 27 randomized, placebo-controlled studies, five of which were classified as chronic migraine, suggests that Botox is associated with improvement in patients with chronic migraine.”
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