On the same day it announced a black box warning for Botox (Allergan, Inc) and similar drugs, the Food & Drug Administration (FDA) approved another botulinum toxin product for injection in the U.S. market. Like Botox and Botox Cosmetic, Dysport is made from botulinum toxin type A. It was approved by the FDA on Thursday, April 30th as both an anti-wrinkle treatment and for treating spasm of the neck muscles. The drug is to be distributed in the U.S. by Medicis Pharmaceutical Corp. of Scottsdale (the manufacturer of the popular soft tissue filler, Restylane) and its partner, France’s Ipsen SA. The cosmetic version of Dysport should be available in the U.S. within the next 30 to 60 days. The medical form should be available during the second half of the year. Some say the newer Reloxin may last longer and may cost less since more dilution can be done in the reconstitution process (whereby a certain volume injectable saline is mixed with the purified toxin prior to injection). Others say the two substances are not interchangeable since Dysport may have a tendency to disperse into surrounding muscles and affect their function in a different way than Botox. Regardless, physician training is of utmost importance prior to injection any patient with either Botox or Dysport.
The same day the FDA approved Dysport, it ordered the manufacturers of botulinum toxin injection products to add black box warnings - the agency’s strictest safety alert - to their labels regarding their risk of potentially life-threatening complication when the effects of the toxin spread far beyond the injection site. According to the FDA, such an occurrence can cause symptoms similar to those of botulism, including unexpected muscle weakness, hoarseness, trouble breathing, difficulty swallowing, double vision, blurred vision and drooping eyelids (levator ptosis). The agency said such symptoms have mostly been reported in children with cerebral palsy being treated with the products for muscle spasticity, an unapproved use of the drugs. Symptoms have also been reported in adults treated both for approved and unapproved uses.
The new warning label will apply to Dysport, as well as Allergan’s Botox and Botox Cosmetic and Solstice Neurosciences’ Myobloc. Botox Cosmetic is approved as a wrinkle treatment including injection into the muscles between the brows that cause brow depression called the corrugator supercilii and procerus. Myobloc and Botox are approved for the treatment of spasms of the neck muscles. Botox is also approved for the treatment of severe underarm sweating (primary axillary hyperhidrosis), crossed eyes (strabismus), and abnormal tics and twitches of the eyelids (blepharospasm). These are very effective products for all of the above indications, and 2.5 million injections of Botox were performed in the US in 2008, making it the most popular cosmetic treatment that year. I perform Botox injections many times per week, and find a high degree of patient satisfaction and loyalty associated with the treatment because it works so well for the treatment of dynamic glabellar wrinkles, forehead furrows (frontalis muscle) and crow's feet (lateral orbicularis oculi muscle).
I think it is important to note that the majority of problems in the past with Botox injections were caused in patients who had chronic underlying medical conditions who were injected with the drug for medical reasons such as cervical spasm or muscle contracture. A direct causal link often cannot be established in such cases. The drug Botox Cosmetic, used for wrinkles with superficial facial muscle contraction, is actually very safe, predictable, and has reproducible results when injected correctly. Dysport (called Reloxin in the U.S.) and Botox Cosmetic must, however, be injected by trained professionals with an intimate understanding of the 3-dimensional anatomy of the face, and patient safety is paramount with any injectable. Untrained injectors and injection of copycat or bootlegged, FDA-unapproved products are a major concern as well that have led to some of the negative press surrounding these products. Botox is a product that has been around for decades in the fields of opthalmology and neurology prior to making its debut in the arena of cosmetic procedures. I would be interested to know what the opinion is of the others--do you think Dysport, or Reloxin, will ever top the gigantic Botox market? Join the discussion with me on Medscape Blogs by WebMD.