Allergan needs REMS, source data documentation for Botox approval

Allergan receives a "complete response" letter from FDA for its Botox (botulinum toxin type A) sBLA for upper limb spasticity in post-stroke adults that identifies three items that Allergan must complete before the agency signs off on the new use. One of the items is a Risk Evaluation and Mitigation Strategy that FDA has put in place for all botulinum toxin products for all uses; Allergan's program should mimic the one that accompanied the approval of Ipsen/Medicis' Dysport. Allergan has already submitted a REMS, but the agency has not yet reviewed it. FDA also wants a safety update from clinical and non-clinical studies across all Botox indications. Further, the agency asked the company to independently verify underlying patient source documentation at study sites relating to one of the pivotal trials conducted in 1999, and provide an updated analysis; the firm estimates this will take 60 to 90 days. The final item in the action letter, regarding revisions to proposed labeling, contains a boon for Allergan. FDA "noted the focal nature of Botox treatments and the similarities of spasticity across conditions, and thus proposed revised labeling that would broaden the indication of use to upper limb spasticity regardless of cause," Allergan reports. The agency also requested a post-approval study in pediatric patients because of the frequency of upper limb spasticity in juvenile cerebral palsy patients. "Allergan hopes to discuss with the FDA a protocol that, if successful, would support an approval for the treatment of children suffering from spasticity," the firm adds