FDA Approves Botox for Pediatric Patients with Upper Limb Spasticity

A PPM Brief

Allergan (Dublin, Ireland) announced¹ FDA approval of botulinum toxin-A (Botox) for the treatment of pediatric patients (ages 2 to 17 years) with upper limb spasticity. Due to brain and spine damage, spasticity results in muscle tightness and stiffness in the upper and lower limbs. Common causes of spasticity in children include cerebral palsy, traumatic brain injury, multiple sclerosis, and stroke.

FDA granted approval after two Phase 3 safety and efficacy studies: a 12-week, double-blind study and a one-year open-label extension study:

• The placebo-controlled, double-blind study in children with upper limb spasticity included 235 patients who were randomized to one intramuscular injection of Botox 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 (Botox 6 units/kg, - 1.87; Botox 3 units/kg, - 1.92; P < 0.001). The improvement was significant at all assessments during the 12-week trial.²
• The open-label study of 222 participants focused Botox’s safety, with the primary outcome being the percentage of patients reporting at least one adverse effect over the course of 60 weeks.³

FDA is also reviewing an additional sBLA for the use of Botox to treat pediatric patients with lower limb spasticity. (Source: 123RF)

The recommended dose of Botox for pediatric patients is 3 units/kg to 6 units/kg divided among the affected muscles of the upper limb; total dosage should not exceed 8 units/kg body weight or 300 units (whichever is lower) in a 3-month interval. Botox treatment should not be used to replace existing physical therapy or other rehabilitation that may have been previously prescribed, noted the company’s press release.

“Pediatric upper limb spasticity is a significant concern and can negatively impact a child's development and quality of life,” said Mark Gormley, Jr., MD, pediatric rehabilitation medicine specialist at the Gillette Children's Specialty Healthcare Hospital in St. Paul, MN, in the company press release. “Because spasticity is particularly debilitating to growing children, it requires ongoing care. Botox has a well-established safety and efficacy profile and I believe it will be an important treatment option in helping successfully manage upper limb spasticity in children and adolescents.”

Allergan was previously granted a six-month Priority Review by FDA for Botox; the drug is also being reviewed as a supplemental biologic application for use in pediatric patients with lower limb spasticity, with a decision expected in Q4 2019.