« Back

Allergan's Botox approved for upper limb spasticity

Wednesday, March 10 2010 | Comments

---

What's This? The Food and Drug Administration approved Allergan Inc.'s Botox (onabotulinumtoxinA) for the treatment of increased muscle stiffness in the elbow, wrist and fingers in adults with upper limb spasticity.

The firm's Biologics License Application was originally submitted for this indication in the poststroke setting, but in a complete response letter the FDA sent to Allergan last May, it suggested the company broaden the indication beyond just upper limb spasticity in adults after a stroke to upper limb spasticity regardless of underlying cause.

In addition to stroke, upper limb spasticity can be observed after a traumatic brain injury or in patients with multiple sclerosis, among other conditions, according to the FDA.

Allergan cited three double-blind studies that support the use of Botox for the treatment of upper limb spasticity. One included 126 individuals who had experienced a stroke six or more months before the start of the study. All subjects had increased levels of wrist and finger flexor tone. They were randomized to receive Botox at a dose ranging from 200 U to 240 U or placebo for 12 weeks. Treatment with Botox led to a statistically significant reduction in both wrist flexor and finger flexor muscle tone at six weeks, a primary endpoint measure.

A similar trial included 91 patients, all of whom had experienced a stroke six or more weeks before study entry and had increased elbow flexor and wrist flexor tone. Treatment with placebo or Botox at doses ranging from 90 U to 360 U lasted 24 weeks. These results showed that the individuals treated with 360 U of Botox had a statistically significant reduction in wrist flexor tone at the six-week primary endpoint as compared with those who received placebo.

Another study using this same Botox dosing range (90 U to 360 U) among 88 patients who had experienced a stroke at least six weeks before study entry and had increased elbow flexor as well as increased wrist and/or finger flexor tone demonstrated decreased muscle tone and statistically significant decreases in wrist flexor tone, finger flexor tone and elbow flexor tone with 360 U of Botox at four weeks relative to treatment with placebo.

The FDA noted that Botox has a boxed warning indicating that the toxin's effects could spread from the injection site to other regions of the body, causing symptoms similar to those of botulism.

Other U.S. indications of Botox include the treatment of the eye conditions blepharospasm and strabismus, abnormal head position and neck pain associated with cervical dystonia and severe primary axillary hyperhidrosis (excess underarm sweating). Botox Cosmetic is indicated for temporary improvement in the appearance of moderate to severe facial glabellar lines.

Print  |  E-mail