Could Results for Revance's Novel Botulinum Toxin Make a Biosimilar Botox Less Appealing?

Drug maker Revance Therapeutics has announced positive results from its SAKURA clinical program for its daxibotulinumtoxinA, a novel botulinum toxin type A that it hopes will compete with brand-name Botox, or onabotulinumtoxinA.

According to Revance, a pooled analysis of the SAKURA 1 and 2 pivotal studies and the SAKURA 3 open-label safety study, which investigated the proposed drug in aesthetic indications, showed that, between patients who received prior botulinum toxin treatment and new patients, the magnitude and duration of clinical efficacy were similar, as was the safety profile.

“I think it is quite interesting to note the results from the pooled analyses, as they illustrate that previous…treatment may not be a factor in the clinical efficacy or duration of effect of [daxibotulinumtoxinA],” said Joel L. Cohen, MD, who presented the results at the American Society for Dermatologic Surgery 2019 Annual Meeting in Chicago, Illinois. “These data give me confidence that [daxibotulinumtoxinA] will be an appropriate, effective, and predictable treatment option for patients who may switch…as well as those that are new to neuromodulators.”

Other data presented at the meeting showed that response rates and duration of effect were highly consistent from treatment cycle to treatment cycle, and that no new safety concerns arose with the novel product.

Results for daxibotulinumtoxinA come as the future of a proposed biosimilar onabotulinumtoxinA, also developed by Revance, is in question. In August of this year, in a filing with the US Securities and Exchange Commission, Revance said that it had amended its agreement with Mylan, giving Mylan extra time to decide whether to continue to develop and eventually commercialize the proposed biosimilar.

Mylan now has until April 2020, or 30 days from the date on which Revance supplies certain deliverables, to notify Revance of its decision on whether to forge ahead with a biosimilar. Mylan previously agreed to pay Revance $5 million, incremental to a previously agreed upfront payment of $25 million, contingent payments of up to $100 million, and sales milestones payments of up to $225 million plus royalties.

A potential benefit of developing a biosimilar of onabotulinumtoxinA is that it is approved for therapeutic indications (including incontinence due to neurological conditions, prophylaxis of headache in patients with migraine, upper limb spasticity, cervical dystonia, and strabismus) in addition to its aesthetic uses, and a biosimilar could potentially gain such indications through extrapolation.

However, Revance has indicated that it could seek therapeutic indications for its novel daxibotulinumtoxinA as well; the company is currently enrolling patients in clinical programs in upper limb spasticity and plantar fasciitis, and that it is also investigating the product’s use in migraine.