Patients with post-stroke spasticity (PSS) commonly experience pain in affected limbs, which may impact quality of life.
To assess onabotulinumtoxinA for pain in patients with PSS from the BOTOX® Economic Spasticity Trial, a multicenter, randomized, double-blind, placebo-controlled trial.
Patients with PSS (N=273) were randomized to 22- to 34-weeks double-blind treatment with onabotulinumtoxinA + standard care (SC) or placebo injection + SC and were eligible to receive open-label onabotulinumtoxinA up to 52 weeks. Assessments included change from baseline on the 11-point pain numeric rating scale, proportion of patients with baseline pain ≥4 achieving ≥30% and ≥50% improvement in pain, and pain interference with work at week 12, end of double-blind treatment, and week 52.
At baseline, most patients (74.3%) experienced pain and 47.4% had pain ≥4 (pain subgroup). Mean pain reduction from baseline at week 12 was significantly greater with onabotulinumtoxinA + SC (–0.77, 95% CI –1.14 to –0.40) than placebo + SC (–0.13, 95% CI –0.51 to 0.24; P < 0.05). Higher proportions of patients in the pain subgroup achieved ≥30% and ≥50% reductions in pain at week 12 with onabotulinumtoxinA + SC (53.7% and 37.0%, respectively) compared with placebo (28.8% and 18.6%, respectively;P<0.05). Reductions in pain were sustained through week 52. Compared with placebo + SC, onabotulinumtoxinA consistently reduced pain interference with work.
This is the first randomized, placebo-controlled trial demonstrating statistically significant and clinically meaningful reductions in pain and pain interference with work with onabotulinumtoxinA in patients with PSS.
Pain prevalence varies widely (10–70%) among post-stroke patients 1, 2, 3 and 4. Several mechanisms may contribute to this range (e.g., peripheral nerve damage, soft tissue trauma, central post-stroke pain, complex regional pain syndrome 5, 6, 7 and 8). Spasticity and pain are factors contributing to “learned non-use” of the affected limb and are often disabling, interfering with daily activities, sleep, walking, physiotherapy, leisure activities, and ultimately affecting patients’ quality of life 9, 10 and 11.
In randomized, double-blind, placebo-controlled trials, onabotulinumtoxinA has been shown to significantly reduce excess muscle tone and decrease disability among patients with upper-limb spasticity 12 and 13, and to further reduce spasms and improve gait in patients with lower-limb spasticity 14 and 15. OnabotulinumtoxinA is effective at reducing pain in patients with cervical dystonia and chronic migraine 16. Prospective open-label studies have shown that onabotulinumtoxinA can reduce pain in patients with post-stroke spasticity (PSS) 8, 17 and 18. However, the efficacy of onabotulinumtoxinA in reducing pain in patients with PSS has not been demonstrated in a large, randomized, placebo-controlled study.
The BOTOX® Economic Spasticity Trial (BEST) was a prospective clinical trial designed to compare the efficacy of onabotulinumtoxinA or placebo (in addition to standard care [SC]) in helping patients with PSS achieve their personal functional goals 19. Here we present results from BEST comparing the effectiveness of onabotulinumtoxinA + SC versus placebo + SC on pain.