Europe's version of Botox, Dysport (Ibsen-Biotech Laboratories) is poised to officially cross the Atlantic, mainly into the offices of U.S. cosmetic surgeons, once Food and Drug Administration (FDA) approval is obtained by its U.S. marketer, Santa Barbara, Calif.-based Inamed.
From there, the product trademarked as Reloxin is likely to break into the U.S. market on the coattails of powerful filler partners marketed by Inamed. The company recently announced a likely merger with Medicis, and offers the entire spectrum of collagen and hyaluronic acid fillers that currently dominate the market.
This is the prediction of Joel L. Cohen, M.D., a Denver-based dermatologic surgeon who is presently a participant in one of the FDA Reloxin studies.
"It will be interesting to see what happens. It is a unique situation for a filler company - now likely two filler companies - to have a botulinum toxin product as well," Dr. Cohen tells Dermatology Times.
A little history...
The introduction and use of Dysport /Reloxin in Europe, he says, parallels that of Botox in the United States. Both are injectable forms of sterile, purified botulinum toxin that have been used for medical and cosmetic uses since the early 1990s. While both are made from Clostridium botulinum toxin Type A and have the same protein content, Reloxin's albumin content is lower.
"As both are Type A toxins, they literally have the same mechanism of action through SNAP-25," Dr. Cohen says.
This was not the case with an earlier potential Botox rival, Myobloc/Neurobloc (Solsice Neurosciences, Inc.). A type B botulinum toxin approved for neurological use in patients with cervical dystonia in 2000, Myobloc faded from the off-label cosmetic market after it was found to have a shorter duration of action, larger diffusion pattern and to cause greater pain on injection than Botox.
While Dr. Cohen emphasizes the similarities between Botox and Reloxin, he notes that physicians may find themselves scrambling for their calculators, thanks to differences that pertain to dosing.
"The Reloxin product simply comes from another source of botulinum type A toxin and it is tested with a different mice strain. Both (are) factors in accounting for the fact that the units are different than Botox. Some neurological studies done with high dosages have indicated a conversion ratio of about 3 units of Dysport/Reloxin to 1 unit of Botox. For example, a glabella that would require 20 to 25 units of Botox would need 50 to 75 units of Reloxin."
Physicians are accustomed to the Botox dosing regimen. Dr. Cohen notes that dosing differences for Reloxin will pose a learning curve for physicians, and a possible stumbling block for Reloxin.
"That's the huge factor in which Reloxin is going to have to play catch-up. We physicians for a while are still going to first consider what a patient would need in Botox units, then do the conversion factor math when we plan to use Reloxin," he asserts.
Botox vs. Reloxin: marketing advantages
Given that the products are so similar, Dr. Cohen discusses the marketing advantages of each in terms of how the competition is likely to heat up and play out.
"Botox is a wonderful and safe product which has developed enormous patient recognition and surely earned physician loyalty," he maintains.
It enjoys the "first to market" advantage, in the tradition of Kleenex and Xerox. Long after other toxins join the field, the public will think of all neurotoxins simply as "Botox."