WASHINGTON (Reuters Health) Dec 27 - Allergan announced on Wednesday that the US Food and Drug Administration (FDA) has approved Botox (botulinum toxin type A) Purified Neurotoxin Complex for the treatment of cervical dystonia in adults.
Patients with cervical dystonia experience involuntary muscle contractions that force the head and neck into abnormal and sometimes painful positions. "Botox decreases the severity of abnormal head position and neck pain associated with this condition by blocking the release of the neurotransmitter acetylcholine from the peripheral nerve terminal to the muscle," Irvine, California-based Allergan explained.
To support the new indication, Allergan conducted a phase III trial involving 170 patients with a mean duration of cervical dystonia of 11 years. The patients who received Botox injections "showed significantly greater improvements than placebo subjects in decreasing the severity of abnormal head position and neck pain," Allergan said.
Allergan noted that the American Academy of Neurology has endorsed the use of Botox for the treatment of cervical dystonia.
Botox is approved in 40 other countries as a cervical dystonia therapy. The drug previously received FDA approval for the treatment of strabismus (crossed eyes) and blepharospasm (uncontrollable blinking), Allergan spokesperson Christine Cassiano told Reuters Health. Allergan has marketed the product in the US for more than 10 years.
Last year, Botox generated $176 million in sales, which represents a 40% increase in sales from the previous year. For the first 9 months of this year, Botox sales increased by 42% compared with the same period last year to $173 million.
Because Botox is already on the market for other indications and has probably been used off-label for the treatment of cervical dystonia, Cassiano said, "I don't know how much of an impact [the new FDA approval] will have" in terms of distribution and sales.
But she added, "Anytime we get FDA approval that's certainly a positive because it allows us to support physicians" using Botox to treat cervical dystonia.
Allergan is currently studying Botox's potential for treating brow furrow and neurological conditions, such as cerebral palsy, Cassiano said. She added that the company "anticipates filing for brow furrow relatively soon with FDA."
Allergan is also studying the drug's use in treating migraine headaches. Botox has been used for several years for reducing facial wrinkles.
Botox will compete with Elan's Myobloc (botulinum toxin type B), which received FDA approval earlier this month for treatment of cervical dystonia.
In a research note issued on Wednesday, Credit Suisse First Boston analyst David Maris said, "after discussions with opinion leaders in the filed, we anticipate physicians will favor treatment with Botox, as compared to Myobloc, due to concerns of potential antibody development and clinical resistance which has arisen as a concern due to Myobloc's protein load which, according to our physician contacts, is several times that of Botox."
Allergan shares rose
3-1/16 to 99 in late morning trade on the New York Stock Exchange on Wednesday.
Shares in Dublin, Ireland-based Elan slipped 9/16 to 47-7/16.
2000 Reuters Ltd.