Evidence-based review of safety and efficacy in cerebral palsy

Safety and Real-World Dosing of OnabotulinumtoxinA for the Treatment of Adult Spasticity: Post Hoc Analysis of the Adult Spasticity International Registry Study

OBJECTIVE

The aim of the study is to evaluate the safety of onabotulinumtoxinA treatment for spasticity across dose ranges in real-world practice.

DESIGN

Adult Spasticity International Registry was a multicenter, prospective, observational study (NCT01930786) of onabotulinumtoxinA treatment for adult spasticity over 2 yrs. Adverse events, serious adverse events, treatment-related adverse events, and serious treatment-related adverse events were sorted into five categories (≤200, 201-400, 401-600, 601-800, ≥801 U) based on cumulative dose per session.

RESULTS

In 3103 treatment sessions ( T ), 730 patients received ≥1 dose of onabotulinumtoxinA. Dose categories included the following: ≤200 U ( n = 312, T = 811), 201-400 U ( n = 446, T = 1366), 401-600 U ( n = 244, T = 716), 601-800 U ( n = 69, T = 149), and ≥801 U ( n = 29, T = 61). Of these patients, 261 reported 827 adverse events, 94 reported 195 serious adverse events, 20 reported 23 treatment-related adverse events, and 2 patients treated with 201-400 U onabotulinumtoxinA reported 3 serious treatment-related adverse events. Treatment-related adverse events reported included ≤200 U (8/811, 0.9%), 201-400 U (7/1366, 0.5%), 401-600 U (6/716, 0.8%), 601-800 U (1/149, 0.7%), and ≥801 U (1/61, 1.6%).

CONCLUSIONS

In this post hoc analysis, most treatment sessions were performed with 201-400 U onabotulinumtoxinA. Patients treated with 201-400 U onabotulinumtoxinA had an adverse event profile consistent with onabotulinumtoxinA package inserts globally (e.g., United States, European Union, United Kingdom, Canada). No new safety signals were identified.

[Multilevel botulinum toxin treatment in severe spastic forms of cerebral palsy (GMFCS IV-V)]

OBJECTIVE

To evaluate the most typical target muscles and dosages for the first and repeated botulinum toxin A (BTA) injections in cerebral palsy (CP) patients with severe motor deficit - GMFCS IV-V.

MATERIAL AND METHODS

A retrospective analysis of 677 protocols of the first and repeated Abobotulinumtoxin A (AboA) injections in 333 patients with CP GMFCS IV and V, aged 1 to 18 years, was carried out.

RESULTS

Ninety-seven percent of patients received multilevel injections. In the lower extremities the most typical target muscles were: m.gracilis - 221 (66.4%) patients, hip adductors - 164 (49.2%), medial hamstring - 144 (43.2%). In the upper extremities the most typical muscles were: m.pronator teres - 237 (71.2%) patients, m.biceps brachii+m.brachialis - 197 (59.2%). The total dosages of AboA and dosages for every target muscle were calculated. Several patients required high dosages (more than 30 U/kg of AboA). Higher dosages per kg were used in younger children and for repeated injections. The age-related evolution of spastic patterns was described. Adverse events were observed in 36 cases (5.3% of all injections).

CONCLUSION

The majority of patients with GMFCS IV-V required multilevel BTA injections in high dosages, especially in young age. Described selection of target muscles and dosages of AboA could be taken into account as a practical experience and reference for the BTA therapy in GMFCS IV-V patients.

Long-Term Observational Results from the ASPIRE Study: OnabotulinumtoxinA Treatment for Adult Lower Limb Spasticity

INTRODUCTION

OnabotulinumtoxinA treatment for spasticity varies according to numerous factors and is individualized to meet treatment goals.

OBJECTIVE

To explore real-world onabotulinumtoxinA utilization and effectiveness in patients with lower limb spasticity from the Adult Spasticity International Registry (ASPIRE) study.

DESIGN

Two-year, multicenter, prospective, observational registry (NCT01930786).

SETTING

Fifty-four international clinical sites.

PATIENTS

Adults (naïve or non-naïve to botulinum toxin[s] treatment for spasticity, across multiple etiologies) with lower limb spasticity related to upper motor neuron syndrome.

INTERVENTIONS

OnabotulinumtoxinA administered at the clinician's discretion.

MAIN OUTCOME MEASURES

OnabotulinumtoxinA treatment utilization, clinician- and patient-reported satisfaction.

RESULTS

In ASPIRE, 530 patients received ≥1 onabotulinumtoxinA treatment for lower limb spasticity (mean age, 52 years; stroke, 49.4%; multiple sclerosis, 20.4%). Equinovarus foot was treated most often (80.9% of patients), followed by flexed knee (26.0%), stiff extended knee (22.5%), and flexed toes (22.3%). OnabotulinumtoxinA doses ranged between 10 and 1100 U across all presentations. Electromyography (EMG) was most commonly used for injection localization (≥41.1% of treatment sessions). Despite low patient response on the satisfaction questionnaire, clinicians (94.6% of treatment sessions) and patients (84.5%) reported satisfaction/extreme satisfaction that treatment helped manage spasticity, and clinicians (98.3%) and patients (91.6%) would probably/definitely continue onabotulinumtoxinA treatment. These data should be interpreted with care. Twenty-one adverse events (AEs) in 18 patients (3.4%) were considered treatment-related. Sixty-seven patients (12.6%) reported 138 serious AEs; 3 serious AEs in two patients (0.4%) were considered treatment-related. No new safety signals were identified.

CONCLUSIONS

ASPIRE provides long-term observational data on the treatment of lower limb spasticity with onabotulinumtoxinA. Real-world data from this primary analysis can help to guide the clinical use of onabotulinumtoxinA to improve spasticity management.

Efficacy of Repeat AbobotulinumtoxinA (Dysport®) Injections in Improving Gait in Children with Spastic Cerebral Palsy

Purpose: This secondary analysis of a randomized, double-blind study plus open-label extension (NCT01249417/NCT01251380) evaluated the efficacy of abobotulinumtoxinA versus placebo in improving gait pattern in children with dynamic equinus due to cerebral palsy (CP) as assessed by the observational gait scale (OGS). Methods: Ambulatory children with CP (N = 241, aged 2-17) and dynamic equinus were randomized to treatment with abobotulinumtoxinA (10 or 15U/kg/leg) or placebo injected into the gastrocsoleus. All children received abobotulinumtoxinA in the open-label phase. Results: In the double-blind phase, abobotulinumtoxinA significantly improved OGS total scores versus placebo at Week 4 (treatment effect vs. placebo: 10U/kg/leg: 1.5 [0.7, 2.3], p = .0003; 15U/kg/leg: 1.1 [0.3, 1.9], p = .01). In the open-label phase, treatment with abobotulinumtoxinA continued to improve the OGS score at the same magnitude as seen in the double-blind study. Conclusion: Repeat treatment with abobotulinumtoxinA improved gait in children with dynamic equinus.

Individualized OnabotulinumtoxinA Treatment for Upper Limb Spasticity Resulted in High Clinician- and Patient-Reported Satisfaction: Long-Term Observational Results from the ASPIRE Study

Introduction

OnabotulinumtoxinA treatment for spasticity is dependent on numerous factors and varies according to selected treatment goals.

Objective

To examine real‐world onabotulinumtoxinA treatment utilization and effectiveness in patients with upper limb spasticity over 2 years from the Adult Spasticity International Registry (ASPIRE) study.

Design

Multicenter, prospective, observational registry (NCT01930786).

Setting

Fifty‐four international clinical sites in North America, Europe, and Asia.

Patients

Adults (naïve or non‐naïve to botulinum toxins for spasticity) with upper limb focal spasticity related to upper motor neuron syndrome across multiple etiologies.

Interventions

OnabotulinumtoxinA administered at clinician's discretion.

Main Outcome Measures

OnabotulinumtoxinA utilization, clinician and patient satisfaction.

Results

Four hundred eighty‐four patients received ≥1 treatment of onabotulinumtoxinA for upper limb spasticity. Patients were on average 55.1 years old, 50.8% male, predominantly Caucasian (72.3%), and 38.6% were naïve to botulinum toxins. Stroke was the most frequently reported underlying etiology (74.0%). Most patients (81.2%) had moderate to severe spasticity at baseline. The most commonly treated upper limb clinical presentation was clenched fist (79.1% of patients). Across all presentations, onabotulinumtoxinA doses ranged between 5‐600U. Electromyography (EMG) was most often utilized to localize muscles (≥57.0% of treatment sessions). Clinicians (92.9% of treatment sessions) and patients (85.7%) reported being extremely satisfied/satisfied that treatment helped manage spasticity, and clinicians (98.6%) and patients (92.2%) would definitely/probably continue onabotulinumtoxinA treatment. One hundred seventy‐nine patients (37.0%) reported 563 adverse events (AEs); 15 AEs in 14 patients (2.9%) were considered treatment related. Sixty‐nine patients (14.3%) reported 137 serious AEs; 3 serious AEs in 2 patients (0.4%) were considered treatment related. No new safety signals were identified.

Conclusions

ASPIRE captured the real‐world individualized nature of onabotulinumtoxinA utilization for upper limb spasticity over 2 years, with consistently high clinician‐ and patient‐reported satisfaction. Data in this primary analysis will guide clinical use of onabotulinumtoxinA, as well as provide insights to improve educational programs on spasticity management.

Cerebral palsy and bruxism: Effects of botulinum toxin injections-A randomized controlled trial

Objective

Cerebral palsy (CP) includes disturbances in muscular control caused by perinatal brain injury. Masticatory muscle involvement hampers functions such as chewing and talking. Bruxism and temporomandibular disorders are overrepresented. Neuromuscular blocks with botulinum toxin type A (BTX‐A) may alleviate problems due to muscular hyperactivity. The aim was to evaluate masticatory muscle BTX‐A injections in subjects with CP and bruxism.

Methods

A prospective, parallel, randomized, placebo‐controlled, and double‐blind trial in 12 patients with CP was performed. End points were alterations in objective and subjective oral capacities after two BTX‐A or corresponding placebo injections. Matched, healthy references were also evaluated.

Results

The reference group demonstrated stronger and more efficient oral functions compared with the CP group. Subjective and objective oral capacities appeared to vary considerably between CP patients and also over time in this patient group and were poorly correlated. No significant effect of BTX‐A compared with placebo on outcome variables was observed at group level, but continued treatment with BTX‐A was requested by the majority of the patients.

Conclusion

The evidence is unable to support the use of BTX‐A for the treatment of affected masticatory muscles in CP, but the findings are inconclusive in certain respects. Larger, more homogeneous groups of CP patients need to be evaluated in future trials.

Muscle volume alterations after first botulinum neurotoxin A treatment in children with cerebral palsy: a 6-month prospective cohort study

AIM

This study aimed to track alterations in muscle volume for 6 months in children with cerebral palsy (CP) after the first exposure to botulinum neurotoxin A (BoNT-A), a commonly used focal spasticity treatment.

METHOD

Eleven ambulant children (eight males, three females) with spastic CP, mean age 8 years 10 months (SD 3y 1mo) participated. Participants received injections to the affected gastrocnemius. The muscle volume of the gastrocnemius, soleus, tibialis anterior, and hamstrings was measured using magnetic resonance imaging. Muscle volume was normalized to bone length, and changes analysed relative to baseline. Assessments were conducted 1 week before, and 4 weeks, 13 weeks, and 25 weeks after BoNT-A treatment.

RESULTS

All children demonstrated positive clinical and functional gains. Muscle volume of the injected gastrocnemius was found to be significantly reduced at 4 weeks (-5.9%), 13 weeks (-9.4%), and 25 weeks (-6.8%). Significant increases in normalized soleus muscle volume were identified at each follow-up, while hamstrings showed significant increase at 4 weeks only.

INTERPRETATION

Absolute and normalized muscle volume of the injected muscle reduces after first BoNT-A exposure, and does not return to baseline volume by 25 weeks. Hypertrophy is seen in the soleus up to 25 weeks; the volume of the plantar flexor compartment is stable.

WHAT THIS PAPER ADDS

Muscle atrophy after first botulinum neurotoxin A (BoNT-A) exposure in children with cerebral palsy is noted. Mild BoNT-A-induced muscle atrophy is still apparent 6 months after BoNT-A exposure. Hypertrophy is evident in soleus after gastrocnemius BoNT-A exposure. Total plantarflexor volume is unchanged.

[Efficacy and safety of botulinum toxin type A (IncobotulinumtoxinA) in the treatment of patients with cerebral palsy]

AIM

To assess the safety and clinical and neurophysiological efficacy of xeomin in children with spastic equinus and equinovarus foot deformity in cerebral palsy.

MATERIAL AND METHODS

Sixty-four patients with spastic forms of cerebral palsy (levels I-IV on the GMFCS) were enrolled into this multi-center open-label comparative randomized trial. The patients were administered xeomin or botox once, each drug being administered to 32 patients. Efficacy was evaluated based on clinical characteristics (the modified Ashworth scale, goniometry) and electromyography data. The subjects were observed for 3 months (90±7 days) after injections. The incidence, severity and intensity of adverse events (AE) was also determined.

RESULTS

Treatment with xeomin according to the suggested protocol has proven its high clinical efficacy. The efficacy was demonstrated by significant, stable and long-term decrease in the gastrocnemius muscle tone: in the xeomin group, the score on the modified Ashworth scale decreased from 2.6±0.49 points at baseline to 1.8±0.54 points (р<0.000001, paired t-test; р<0.000004, Wilcoxon test). In the botox group, this score decreased from 2.4±0.56 points to 1.6±0.45 points (р<0.000001, paired t-test; р<0.000002, Wilcoxon test). The increased range of ankle joint movements at passive and voluntary feet extension. In the xeomin group, the significant proportion of patients (45.1%) moved to the group of lower spasticity defined as less than two score points on the modified Ashworth scale. The clinical data fully matched the changes in electromyography parameters, which were characterized by the lower amplitude and area of the target muscle (lateral and medial gastrocnemius heads) M-responses. AE developed in three patients (9.4%) administered xeomin and in two patients (6.3%) administered botox. The AE recorded in the study are described in the recommendations on the use of xeomin and botox. In three cases (50.0%), AE intensity was determined as mild, in the remaining three cases (50.0%) as moderate.

CONCLUSION

The results have shown the safety and efficacy of xeomin in the treatment of gastrocnemius spasticity in pediatric patients with cerebral palsy. These data are confirmed by the lack of significant differences in any clinical or electromyography parameters with the results in the reference group administered botox.

Effects of ultrasound-guided botulinum toxin type-A injections with a specific approach in spastic cerebral palsy

The aim of this study was to detect effects of ultrasound-guided botulinum toxin type-A (US-guided BoNT-A) injections prepared according to lower extremity innervation zones on spasticity and motor function in 3-16 years children with diplegic and hemiplegic spastic cerebral palsy. This study included 25 patients between 3 and 16 years of age who admitted to our clinic in 2017, were being followed in our clinic with a diagnosis of cerebral palsy, had BoNT-A injections due to lower extremity spasticity. The US-guided BoNT-A injections were administered into the spastic muscles using a specific approach according to innervation zones of muscle. Modified Ashworth Scale (MAS) and Gross Motor Functional Classification System (GMFCS) were assessed at the baseline, and 4 and 12 weeks after the BoNT-A injections. Minimum and maximum ages of the patients were 45 and 192 months, and gender distribution was 8 females and 17 males. Significant decreases in the MAS scores of the knee and ankle tones were measured 4 and 12 weeks after the BoNT-A injection when compared to the baseline scores (p < 0.025). Hip muscle tonus only decreased 12 weeks after the injection (p < 0.025). In parallel with a reduction in spasticity GMFCS improved from 3 to 2 in the 4th and 12th weeks. US-guided BoNT-A injections with Euro-musculus approach is a practical and effective method to perform injections into proper points of proper muscles in children with spastic cerebral palsy.

Severity of cerebral palsy and likelihood of adverse events after botulinum toxin A injections

AIM

To determine the incidence of common adverse events after botulinum toxin A (BoNT-A) injections in children with cerebral palsy (CP) and to identify whether the severity of CP influences the incidence of adverse events.

METHOD

This was an observational study of patients attending a BoNT-A clinic at a tertiary paediatric hospital (2010-2014). Data examined included procedural adverse events at the time of injection and at follow-up. Systemic adverse events were defined as lower respiratory tract illnesses, generalized weakness, dysphagia, and death. Severity of CP was categorized by the Gross Motor Function Classification System (GMFCS). The relationships between GMFCS and adverse events were analysed using negative binomial regression models.

RESULTS

In total, 591 children underwent 2219 injection episodes. Adverse events were reported during the procedure (130 [6%] injection episodes) and at follow-up (492 [22%] injection episodes). There were significantly increased rates of systemic adverse events in injection episodes involving children in GMFCS level IV (incidence rate ratio [IRR] 3.92 [95% confidence interval] 1.45-10.57]) and GMFCS level V (IRR 7.37 [95% confidence interval 2.90-18.73]; p<0.001).

INTERPRETATION

Adverse events after BoNT-A injections are common but mostly mild and self-limiting. Children in GMFCS levels IV and V are at increased risk of systemic adverse events. The relationship between CP severity and BoNT-A adverse events is complex and further research is required to better understand this relationship.

WHAT THIS PAPER ADDS

Adverse events reported at the time of botulinum toxin A injection occurred in 6% of injection episodes. Adverse events were reported at follow-up in 22% of injection episodes. Children in Gross Motor Function Classification System (GMFCS) levels IV and V have increased rates of systemic adverse events. Children in GMFCS levels IV and V report less local weakness and pain.

AbobotulinumtoxinA (Dysport®) Improves Function According to Goal Attainment in Children With Dynamic Equinus Due to Cerebral Palsy

This secondary analysis of a large (n = 241), randomized, double-blind study evaluated the efficacy of 2 doses of abobotulinumtoxinA + standard of care (SOC) versus placebo + SOC in enabling children with dynamic equinus due to cerebral palsy to achieve their functional goals using Goal Attainment Scaling. Most parents/caregivers selected goals targeting aspects of gait improvement as most relevant. Mean (95% confidence interval) Goal Attainment Scaling T scores at week 4 were higher for both abobotulinumtoxinA groups versus placebo (treatment difference vs placebo: 10 U/kg/leg: 5.32 [2.31, 8.32], P = .0006, and 15 U/kg/leg 4.65 [1.59, 7.71], P = .0031). Superiority of both abobotulinumtoxinA doses versus placebo was maintained at week 12. Best goal attainment T scores were higher in the abobotulinumtoxinA groups versus placebo for the common goals of improved walking pattern, decreased falling, decreased tripping, and improved endurance. These findings demonstrate that single injections of abobotulinumtoxinA (10 and 15 U/kg/leg) significantly improved the ability of pediatric cerebral palsy patients to achieve their functional goals.

Sharpening Host Defenses during Infection: Proteases Cut to the Chase

The human immune system consists of an intricate network of tightly controlled pathways, where proteases are essential instigators and executioners at multiple levels. Invading microbial pathogens also encode proteases that have evolved to manipulate and dysregulate host proteins, including host proteases during the course of disease. The identification of pathogen proteases as well as their substrates and mechanisms of action have empowered significant developments in therapeutics for infectious diseases. Yet for many pathogens, there remains a great deal to be discovered. Recently, proteomic techniques have been developed that can identify proteolytically processed proteins across the proteome. These “degradomics” approaches can identify human substrates of microbial proteases during infection in vivo and expose the molecular-level changes that occur in the human proteome during infection as an operational network to develop hypotheses for further research as well as new therapeutics. This Perspective Article reviews how proteases are utilized during infection by both the human host and invading bacterial pathogens, including archetypal virulence-associated microbial proteases, such as the Clostridia spp. botulinum and tetanus neurotoxins. We highlight the potential knowledge that degradomics studies of host–pathogen interactions would uncover, as well as how degradomics has been successfully applied in similar contexts, including use with a viral protease. We review how microbial proteases have been targeted in current therapeutic approaches and how microbial proteases have shaped and even contributed to human therapeutics beyond infectious disease. Finally, we discuss how, moving forward, degradomics research can greatly contribute to our understanding of how microbial pathogens cause disease in vivo and lead to the identification of novel substrates in vivo, and the development of improved therapeutics to counter these pathogens.

Report of a workshop on research gaps in the treatment of cerebral palsy

Cerebral palsy (CP) is heterogeneous in etiology and manifestations, making research into relevant therapies difficult and limiting the generalizability of the results. We report here on the NIH CP symposium, where stakeholders from academic, clinical, regulatory, and advocacy backgrounds discussed the major challenges and needs for moving forward with clinical research in CP, and outlined priorities and action items. New information is constantly generated through research into pathogenesis and etiology. Clinical research and new therapeutic approaches need to keep pace, through large data registry integration and new research designs. Development of standardized data collection, increasing academic focus on CP research, and iterative approaches to treatment throughout the patients' lives, have all been identified as areas of focus. The workshop identified critical gaps and areas of focus to increase the evidence base for therapeutic approaches to determine which treatments work best for which patients in the near future. These include consolidation and optimization of databases and registries, updates to the research methodology, and better integration of resources and stakeholders.