OnabotulinumtoxinA (Botox ®) may provide pain relief for patients with post-stroke spasticity, according to research published in the Journal of Pain Symptom Management.
The Botox® Economic Spasticity Trial (BEST) “is a unique study that evaluated the efficacy of onabotulinumtoxinA in a setting that reflects usual clinical practice within a controlled trial,” wrote Jörg Wissel, MD, of the Department of Neurology at Vivantes Klinikum Spandau in Berlin, Germany, and colleagues. “To our knowledge, [it] is the first randomized, placebo-controlled trial to demonstrate that onabotulinumtoxinA effectively reduces pain in post-stroke spasticity (PSS).”
To analyze the effects of onabotulinumtoxinA on pain, the researchers recruited 273 participants with PSS ages 18 to 85 years and randomized them to 22- to 34-weeks double-blind treatment with onabotulinumtoxinA plus standard care (SC) or placebo injection plus SC. Participants were eligible to receive open-label onabotulinumtoxinA up to 52 weeks. At baseline, 74.3% of participants experienced pain, and 47.4% experienced pain that was ≥4 on the 11-point pain numeric rating scale.
At week 12, participants in the onabotulinumtoxinA + SC group had significantly greater reductions in pain (–0.77, 95% CI –1.14 to –0.40) than the placebo group (–0.13, 95% CI –0.51 to 0.24; P < 0.05).
There were also higher proportions of participants receiving onabotulinumtoxinA who achieved ≥30% and ≥50% reductions in pain at week 12 (53.7% and 37.0%, respectively) compared with those who achieved ≥30% and ≥50% reductions in pain at week 12 in the placebo group (28.8% and 18.6%, respectively; P<0.05). The reductions in pain were also sustained through week 52.
“Compared with placebo + SC, onabotulinumtoxinA consistently reduced pain interference with work,” the researchers wrote. “When combined with the improvement in muscle tone, onabotulinumtoxinA may have the potential to improve the lives of affected patients with PSS by reducing pain.”
The researchers noted that future studies should aim to confirm onabotulinumtoxinA’s effectiveness in treating pain syndromes in patients with PSS.
Funding for the study was provided by Allergan plc. See full study for author disclosures.
Wissel J, Ganapathy V, Ward AB, et al. OnabotulinumtoxinA Improves Pain in Patients with Post-Stroke Spasticity: Findings from a Randomized, Double-Blind, Placebo-Controlled Trial. J Pain Symptom Manage. 2016; doi:10.1016/j.jpainsymman.2016.01.007.