Pain Reduction in Adults with Limb Spasticity Following Treatment with IncobotulinumtoxinA: A Pooled Analysis

Abstract

Some studies have shown that incobotulinumtoxinA reduces spasticity-associated pain, but further evidence is needed. This exploratory analysis pooled pain-relief data from six Phase 2 or 3 studies of incobotulinumtoxinA (four placebo-controlled studies) for treating upper limb spasticity in adults. Spasticity-associated pain was assessed at baseline and 4 weeks post incobotulinumtoxinA injection using the disability assessment scale (DAS) for pain. Only data for patients with pain at baseline were analysed. Overall, 544 (incobotulinumtoxinA, N = 415; placebo, N = 129) of 937 patients (58.1%) experienced pain at baseline. At Week 4, a significantly greater proportion of incobotulinumtoxinA- (52.1%) than placebo-treated patients (28.7%; Chi-square p < 0.0001) showed a response (≥1-point improvement in DAS pain score). In logistic regression analysis, incobotulinumtoxinA-treated patients were 2.6 times more likely to achieve this endpoint than placebo-treated patients. A significant difference between incobotulinumtoxinA and placebo was observed regardless of baseline pain severity. Additionally, 27.1% of incobotulinumtoxinA- versus 12.4% of placebo-treated patients reported complete pain relief at Week 4 (p = 0.0006). Pain relief increased with multiple injection cycles. To achieve patient-centred care, pain relief may be considered a treatment goal in adults with spasticity-associated pain regardless of pain severity. This study contributes to understanding the benefits of incobotulinumtoxinA in treating limb spasticity-associated pain.

A practical guide to botulinum neurotoxin treatment of shoulder spasticity 2: Injection techniques, outcome measurement scales, and case studies

“…In a recent pooled analysis, repeated incobotulinumtoxinA injections were demonstrated to be effective in reducing UL pain associated with spasticity regardless of baseline pain severity and showed a cumulative effect over time with a greater effect on pain observed after multiple injection cycles ( 2 ). When BoNT-A is introduced early after the onset of spasticity, pain reduction is rapid, being observed after a single BoNT-A injection ( 29 ).…”

“…Botulinum neurotoxin type A (BoNT-A) is an established first-line treatment in focal, multifocal, and segmental spasticity to provide pain relief, to reduce involuntary movements, and to help restore both passive and active functions (1)(2)(3). Most pivotal trials with BoNT-A in the upper limb (UL) spasticity did not include the injection of shoulder muscles (4)(5)(6)(7)(8)(9), although a few recent trials reported the benefits of including shoulder muscles as possible injection targets (10,11).…”

A practical guide to botulinum neurotoxin treatment of shoulder spasticity 1: Anatomy, physiology, and goal setting

“…Spastic movement disorder, as defined by Pandyan et al (1) and herein termed "spasticity", consists of all positive symptoms of upper motor neuron syndrome (UMNS) -normally characterized by increased levels of involuntary motor activity, and including spasticity (a velocity-dependent increase in muscle tone) and spastic dystonia (1)(2)(3). Upper limb (UL) spasticity has been reported to affect as many as 43% of patients up to 12 months post-stroke (4,5) and may be associated with pain following stretching of the muscles and soft tissue involved, deformity, impairment and/or loss of limb function (6,7). This can negatively impact quality of life (QoL) due to the need to depend on others (8) as well as resulting in social isolation and depression (9)(10)(11).…”

“…Botulinum neurotoxin A (BoNT-A) is first-line treatment for focal, multifocal and segmental spasticity and provides pain relief for those with spasticity-associated pain, reduces involuntary movements in UMNS and helps to restore both passive and active function ( 7 , 12 , 13 ). Furthermore, treatment with BoNT-A has been shown to improve patient QoL and has a superior cost-utility ratio compared with conventional oral antispastic therapy in UL spasticity ( 14 ).…”

“…Most pivotal studies of BoNT-A to treat UL spasticity focused on injecting arm, wrist, hand and/or finger muscles and did not include shoulder muscles ( 15 – 20 ), with only two UL spasticity trials including the shoulder ( 21 , 22 ). Furthermore, shoulder muscles are seldom injected with BoNT A in the real-world management of UL spasticity ( 23 ) despite hemiplegic shoulder pain being the most common post-stroke pain disorder ( 24 ) and evidence supporting the possible reduction of this pain by shoulder muscle injection with BoNT-A ( 7 , 21 , 22 , 25 – 27 ). Shoulder spasticity can restrict the functional capacity of the UL, especially the ability of patients to reach for objects such as a light switch, or a doorknob.…”