Dr David NicholsonDavid Nicholson, PhD
The FDA has approved the supplemental biologics license application (sBLA) for onabotulinumtoxinA (Botox) for treatment of pediatric patients, 2­–17 years of age, with upper limb spasticity, Allergan announced.

This therapy, the first neurotoxin treatment approved to treat pediatric patients with upper limb spasticity, is backed by data from 2 phase 3 studies that evaluated the safety and efficacy in more than 200 patients in this population. The trials included a 12-week, double-blind study (NCT01603602) and a 1-year open-label extension study (NCT01603615).

“Watching a child suffering with any degree of upper limb spasticity is very difficult.” David Nicholson, chief research and development officer, Allergan, said in a statement.1 “This FDA approval is special to all of us at Allergan because we can now provide children and their caregivers an advancement in pediatric care with Botox. This milestone underscores our constant focus on innovative and builds on our 30-years of research and development efforts with Botox since FDA approval of blepharospasm and strabismus in 1989. We also look forward to the FDA’s decision on pediatric lower limb spasticity and continuing to serve our patients globally.”

The approved recommended dose per treatment session is 3 Units per kilogram to 6 Units per kilogram divided among affected muscles of the limb, and the total dose should not exceed 6 units per kilogram body weight or 200 Units, whichever is lower, in a 3-month interval.2 Treatment with onabotulinumtoxinA in children 2­–17 years of age with upper limb spasticity is not meant to replace existing physical therapy or other rehabilitation that may be prescribed.

The placebo-controlled, double-blind study in children with upper limb spasticity included 235 patients who were randomized to one intramuscular injection of onabotulinumtoxinA 3 Units/kg or 6 Units/kg, or placebo. The active treatment groups demonstrated a significant reduction in Modified Ashworth Scale-Bohannon scores compared to placebo (onabotulinumtoxinA 6 units/kg, -1.87; onabotulinumtoxinA 3 units/kg, -1.92; P <.001). The improvement was significant at all assessments during the 12-week trial.2

The open-label study, which included 222 participants, focused on safety. The primary outcome included the percentage of patients reporting at least one adverse effect over the course of 60 weeks.

“Physicians have been using onabotulinumtoxinA to successfully treat spasticity for more than 25 years,” Heakyung Kim, MD, the A. David Gurewitsch Professor of Rehabilitation and Regenerative Medicine and Professor of Pediatrics at the Columbia University Medical Center, told NeurologyLive in an interview. “OnabotulinumtoxinA has been demonstrated to be safe to use in the pediatric population and has a high profile of efficacy. Treatments are minimally invasive, and the dosing of the medication is easy to understand. If spasticity management with onabotulinumtoxinA is started at an early age and conducted regularly, we can prevent unnecessary complications and promote improved function throughout growth. If intervention is begun later in life and injections are not done on a regular basis, we may see a decrease in efficacy of onabotulinumtoxinA injections due to a higher likelihood of pre-existing bony deformities or joint contractures that may eventually require orthopedic surgery.”

The FDA is also reviewing an additional supplemental biologics license application for use of onabotulinumtoxinA to treat pediatric patients with lower limb spasticity. A decision is expected in the fourth quarter of 2019.
REFERENCE
1.FDA Approves BOTOX® (onabotulinumtoxinA) for Pediatric Patients with Upper Limb Spasticity [news release]. Dublin: Allergan; June 21, 2019. https://www.prnewswire.com/news-releases/fda-approves-botox-onabotulinumtoxina-for-pediatric-patients-with-upper-limb-spasticity-300872470.html. Accessed June 21, 2019.
2.Botox [prescribing information]. Madison, NJ: Allergan; 2019. https://www.allergan.com/assets/pdf/botox_pi.pdf. Accessed June 21, 2019.