Real-world differences in dosing and clinical utilization of OnabotulinumtoxinA and AbobotulinumtoxinA in the treatment of upper limb spasticity

According to prescribing information, potency units are not interchangeable between botulinum toxin A products. This exploratory study compared real-world dosing and utilization of onabotulinumtoxinA and abobotulinumtoxinA in adults with upper limb spasticity. In this retrospective study, 101 clinicians provided chart data via online surveys for 215 US post-stroke patients treated for upper limb spasticity with ≥3 onabotulinumtoxinA or abobotulinumtoxinA doses (phase 1: 9/18/2020-12/10/2020; phase 2: 9/30/2021-12/7/2021). Most participating clinicians were physicians (70.3%) specializing in neurology (71.3%) or physiatry (20.8%). In the onabotulinumtoxinA (n = 107) and abobotulinumtoxinA (n = 108) groups, ∼75% of patients had moderate-to-severe spasticity. A range of onabotulinumtoxinA:abobotulinumtoxinA dose ratios (1:2.2 [95%CI: 1.8-2.6] to 1:4.1 [95%CI: 3.0-6.0]) was observed across muscles. For the most recent dose, mean number of muscles injected was greater for onabotulinumtoxinA (4.3) versus abobotulinumtoxinA (3.1; P = 0.0003). For onabotulinumtoxinA versus abobotulinumtoxinA, the proportion of injections was 81.3% versus 63.9% (P = 0.0067) in forearm muscles and 23.4% versus 3.7% (P = 0.0001) in hand muscles. Mean injection intervals were similar (onabotulinumtoxinA: 102.0 days; abobotulinumtoxinA: 99.1 days). Differences in real-world dosing and utilization of onabotulinumtoxinA and abobotulinumtoxinA for upper limb spasticity were observed. There was no standard dose-conversion ratio, consistent with each product's prescribing information.

A Cost-Effectiveness and Budget Impact Analysis of AbobotulinumtoxinA in Greece

This study aimed to assess the cost-effectiveness of abobotulinumtoxinA (aboBoNT-A) plus Best Supportive Care (BSC) compared with BSC alone for managing limb spasticity in adult patients in Greece, as well as to conduct a budget impact analysis of the introduction of aboBoNT-A in the Greek healthcare system compared to onabotulinumtoxinA (onaBoNT-A). Clinical studies were utilized to extract data on drug efficacy and patients' utility, while cost data were collected from Greek sources. The results of the study showed that aboBoNT-A plus BSC was a cost-effective treatment option for both upper and lower limb spasticity in adult patients compared to BSC. Additionally, introducing aboBoNT-A into the Greek healthcare system resulted in cost savings in pharmaceutical spending over a 5-year period. The findings suggest that incorporating aboBoNT-A into the Greek healthcare system could improve patient access to treatment and healthcare resource efficiency, as it is a more economical option compared to onaBoNT-A.

A UK Single-Center, Retrospective, Noninterventional Study of Clinical Outcomes and Costs of Two BotulinumtoxinA Treatments for Limb Spasticity

Service model changes at the North Staffordshire Rehabilitation Centre (UK) included switching spasticity treatment from onabotulinumtoxinA (onaBoNT-A) to abobotulinumtoxinA (aboBoNT-A). This noninterventional, retrospective, longitudinal study (NCT04396704) describes the clinical and economic outcomes in toxin-naive adults with spasticity who received onaBoNT-A (Cohort 1; 2015-2017) or aboBoNT-A (Cohort 2; 2017-2019). Outcomes included Goal Attainment Scale T (GAS-T) score, treatment satisfaction, quality of life (QoL; EQ-5D visual analog scale [VAS] score), and treatment costs. Adverse events were recorded for Cohort 2. Cohort 1 included 60 patients (mean [standard deviation] dose, 206.0 [98.8] U); Cohort 2 included 54 patients (753.7 [457.3] U). Mean (95% confidence interval) GAS-T scores for Cohorts 1 and 2 were 43.1 (39.3-46.9) and 47.8 (43.7-51.9) at Week 6, and 43.2 and 44.3 at Week 12, respectively. In both cohorts most patients were satisfied with treatment. At Week 12, QoL had not changed in Cohort 1 but had improved in Cohort 2 (EQ-5D VAS, -5). Mean estimated per-patient costs (in 2021) for Cohorts 1 and 2 were £315.56 and £249.25, respectively, at Week 6, and £343.20 and £273.21, respectively, at Week 12. Fifteen non-treatment-related serious adverse events and two deaths were recorded. These data may warrant a larger prospective study powered to compare outcomes of aboBoNT-A and onaBoNT-A.

Safety and Effectiveness of Repeated Botulinum Toxin A Intracavernosal Injections in Men with Erectile Dysfunction Unresponsive to Approved Pharmacological Treatments: Real-World Observational Data

Intracavernosal injections of botulinum toxin A (BTX/A ic) may be effective for difficult-to-treat erectile dysfunction (ED). This is a retrospective case series study of the effectiveness of repeated off-label BTX/A ic (onabotulinumtoxinA 100U, incobotulinumtoxinA 100U or abobotulinumtoxinA 500U) in men with ED and insufficient response to phosphodiesterase type 5 inhibitors (PDE5-Is) or prostaglandinE1 intracavernosal injections (PGE1 ICIs), defined as an International Index of Erectile Function-Erectile Function domain score (IIEF-EF) < 26 on treatment. Further injections were performed on patients' requests, and the files of men who underwent at least two injections were reviewed. The response to BTX/A ic was defined as the achievement of the minimally clinically important difference in IIEF-EF adjusted to the severity of ED on treatment at baseline. Out of 216 men treated with BTX/A ic and PDE5-Is or PGE1-ICIs, 92 (42.6%) requested at least a second injection. The median time since the preceding injection was 8.7 months. In total, 85, 44 and 23 men received, respectively, two, three and four BTX/A ic. The overall response rate was 77.5%: 85.7% in men with mild ED, 79% for moderate ED and 64.3% for severe ED on treatment. The response increased with repeated injections: 67.5%, 87.5% and 94.7%, respectively, after the second, third and fourth injections. Post-injection changes in IIEF-EF were similar across injections. The time from injection to request for a further injection varied little. Four men reported penile pain at the time of injection (1.5% of all injections), and one experienced a burn at the penile crus. Repeated BTX/A injections combined with PDE5-Is or PGE1-ICIs produced an effective and durable response, with acceptable safety.

Efficacy of abobotulinumtoxinA versus onabotulinumtoxinA for the treatment of refractory neurogenic detrusor overactivity: a systematic review and indirect treatment comparison

AIMS

To compare the efficacy and safety of abobotulinumtoxinA (aboBoNT-A) and onabotulinumtoxinA (onaBoNT-A) for the treatment of refractory neurogenic detrusor overactivity (NDO), using an indirect treatment comparison (ITC).

MATERIALS AND METHODS

A systematic literature review was used to identify randomized controlled trials (RCTs) that evaluated botulinum toxin type A for the treatment of refractory NDO. Treatments were compared using a Bucher ITC approach. Efficacy outcomes were reduction in number of weekly urinary incontinence (UI) episodes at 6, 12, and 24 weeks of follow-up. The safety outcome was the proportion of patients with treatment-emergent urinary tract infections (TE-UTIs) during follow-up. Subgroup/sensitivity analyses were performed to investigate the impact of heterogeneity.

RESULTS

Fifteen studies of botulinum toxin type A were identified. Among these, onaBoNT-A 200 U was the only botulinum toxin type A considered an appropriate comparator for aboBoNT-A 600 U and 800 U. As such, six RCTs that evaluated onaBoNT-A or aboBoNT-A were included in the ITC. In base-case analyses, there were no statistically significant differences between aboBoNT-A and onaBoNT-A in terms of UI episodes or TE-UTIs. Numerically, the trend favored aboBoNT-A (either dose) for all endpoints and time points. At 12 and 24 weeks, the difference in reduction of UI episodes per week was considered clinically relevant when comparing aboBoNT-A 800 U with onaBoNT-A 200 U, but not when comparing the lower dose of aboBoNT-A (600 U) with onaBoNT-A 200 U. Results from subgroup/sensitivity analyses were consistent with the base case.

LIMITATIONS

Heterogeneity across studies was observed; however, strong consistency of trends across analyses suggests the impact of heterogeneity is low.

CONCLUSIONS

There may be potential advantages of aboBoNT-A over onaBoNT-A, in terms of UI reduction, in patients with refractory NDO. More confirmatory studies are needed owing to the sparsity of current evidence.

Post Hoc Subgroup Analysis of the BCause Study Assessing the Effect of AbobotulinumtoxinA on Post-Stroke Shoulder Pain in Adults

Botulinum toxin type A is approved for the focal treatment of spasticity; however, the effectiveness of abobotulinumtoxinA (aboBoNT-A) in patients with shoulder pain who have set reduced pain as a treatment goal is understudied. In addition, some patients encounter delays in accessing treatment programs; therefore, the suitability of aboBoNT-A for pain reduction in this population requires investigation. These factors were assessed in aboBoNT-A-naive Brazilian patients in a post hoc analysis of data from BCause, an observational, multicenter, prospective study (NCT02390206). Patients (N = 49, n = 25 female; mean (standard deviation) age of 60.3 (9.1) years; median (range) time since onset of spasticity of 16.1 (0-193) months) received aboBoNT-A injections to shoulder muscles in one or two treatment cycles (n = 47). Using goal attainment scaling (GAS), most patients achieved their goal of shoulder pain reduction after one treatment cycle (72.1%; 95% confidence interval: 57.2-83.4%). Improvements in GAS T-score from baseline, clinically meaningful reductions in pain score at movement, and clinically meaningful increases in passive shoulder abduction angle further improved with repeated treatment more than 4 months later, despite treatment starting at a median of 16.1 months after the onset of spasticity. These findings support the further investigation of aboBoNT-A injections in chronic post-stroke shoulder pain.

Evaluation of the Safety and Efficacy of a Biosimilar Abobotulinum Toxin Type A in Treating Moderate to Severe Glabellar Lines: A Non-Inferiority Double Blinded Randomized Controlled Trial

BACKGROUND

Injection of botulinum toxin for cosmetic purposes is a well-established practice.

OBJECTIVES

This study was conducted to compare the safety and efficacy of Dyston^® (investigational biosimilar abobotulinumtoxinA) with Dysport^® (abobotulinumtoxinA, Ipsen) in the treatment of moderate to severe glabellar lines.

METHODS

Out of 193 screened subjects, 126 volunteers with moderate to severe glabellar lines fulfilling eligibility criteria were randomized in a 1:1 ratio to receive either an intramuscular injection of 40-60 units of Dyston^® or Dysport^® . The primary objective was to test the non-inferiority of Dyston^® compared to Dysport^® as measured by the percentage of volunteers who achieved no or mild glabellar lines at maximum frown assessed by the physicians based on the Glabellar Line Severity Score (GLSS) at day 30. Secondary endpoints included the improvement in the glabellar lines at maximum frown and rest states at days 14, 60, 90 and 120 as well as the side effects of the treatment.

RESULTS

Response rates at maximum frown were 75.44% (43/57) in the Dyston^® group and 76.67% (46/60) in the Dysport^® group on day 30 (P value: 0.88, 95%CI: -14.24 to 16.70, diff: 1.23) as per-protocol set, and were 75.81% (47/62) and 76.19 (48/63) (P value: 0.96, 95%CI: -14.59 to 15.35, diff: 0.3) in the Dyston^® and the Dysport^® groups, respectively, based on modified intention to treat population. Adverse events were similar in both groups and mostly mild and well-tolerated.

CONCLUSION

Treatment of moderate to severe glabellar lines with Dyston^® was effective, tolerable, and non-inferior compared to Dysport^® .

Muscle Selection and Dosing in a Phase 3, Pivotal Study of AbobotulinumtoxinA Injection in Upper Limb Muscles in Children With Cerebral Palsy

Background: Guidelines recommend botulinum toxin-A in pediatric upper limb spasticity as part of routine practice. Appropriate dosing is a prerequisite for treatment success and it is important that injectors have an understanding on how to tailor dosing within a safe and effective range. We report upper limb dosing data from a phase 3 study of abobotulinumtoxinA injections in children with cerebral palsy.

Methods: This was a double-blind, repeat-treatment study (NCT02106351). In Cycle 1, children were randomized to abobotulinumtoxinA at 2 U/kg control dose or clinically relevant 8 U/kg or 16 U/kg doses. Doses were divided between the primary target muscle group (PTMG, wrist or elbow flexors) and additional muscles tailored to clinical presentation. During Cycles 2–4, children received doses of 8 U/kg or 16 U/kg and investigators could change the PTMG and other muscles to be injected. Injection of muscles in the other upper limb and lower limbs was also permitted in cycles 2–4, with the total body dose not to exceed 30 U/kg or 1,000 U (whichever was lower) in the case of upper and lower limb treatment.

Results: 212 children were randomized, of which 210 received ≥1 abobotulinumtoxinA injection. Per protocol, the elbow and wrist flexors were the most commonly injected upper limb muscles. Across all 4 cycles, the brachialis was injected in 89.5% of children (dose range 0.8–6 U/kg), the brachioradialis in 83.8% (0.4–3 U/kg), the flexor carpi ulnaris in 82.4% (0.5–3 U/kg) and the flexor carpi radialis in 79.5% (0.5–4 U/kg). Other frequently injected upper limb muscles were the pronator teres(70.0%, 0.3–3 U/kg). adductor pollicis (54.3%, 0.3-1 U/kg), pronator quadratus (44.8%, 0.1–2 U/kg), flexor digitorum superficialis (39.0%, 0.5-4 U/kg), flexor digitorum profundus (28.6%, 0.5–2 U), flexor pollicis brevis/opponens pollicis (27.6%, 0.3-1 U/kg) and biceps (27.1%, 0.5–6 U/kg). AbobotulinumtoxinA was well-tolerated at these doses; muscular weakness was reported in 4.3% of children in the 8 U/kg group and 5.7% in the 16 U/kg group.

Conclusions: These data provide information on the pattern of injected muscles and dose ranges used in this study, which were well-tolerated. Per protocol, most children received injections into the elbow and wrist flexors. However, there was a wide variety of other upper limb muscles injected as physicians tailored injection patterns to clinical need.

Botulinum Toxin Type A for Glabellar Frown Lines: What Impact of Higher Doses on Outcomes?

Botulinum toxin serotype-A (BoNT-A) preparations are widely used to improve the appearance of wrinkles. While effective and well tolerated, patients require retreatment over time to re-establish the effects. There is growing interest from patients as to whether higher doses can prolong response without significantly increasing side effects. We reviewed the efficacy and safety evidence for high-dose BoNT-A treatment of glabellar lines, by evaluating high-dose studies published since 2015. Toxins approved for glabellar line treatment in the US or Europe were considered. "High-dose" indicated doses above the licensed dose for each BoNT-A preparation. Five studies met the inclusion criteria and most were randomized, double-blind trials; designs and population sizes varied. Findings suggested that higher-dose BoNT-A treatment is feasible and may improve response duration without increased safety issues. Around 9 months' median duration was achieved with a 2-2.5-fold increase of the abobotulinumtoxinA on-label dose, or with a 5-fold increase in incobotulinumtoxinA dose. A 2-4-fold increase of the onabotulinumtoxinA on-label dose yielded a median duration of around 6 months. Importantly, patient satisfaction and natural look remained with increasing abobotulinumtoxinA doses. While more data are needed, these findings may lead to more effective, individually tailored treatment plans to meet patient expectations.

Botulinum toxin type-A preparations are not the same medications - basic science (Part 1)

Botulinum neurotoxin type A (BoNT/A) formulations are widely used in clinical practice. Although they share a common mechanism of action resulting in presynaptic block in acetylocholine release, their structure and pharmacological properties demonstrate some similarities and many differences. Bioequivalence has been discussed since the onset of the clinical use of BoNT/A. In this review, we provide an update on the studies and compare the molecular structure, mechanisms of action, diffusion and spread, as well as immunogenicity and dose equivalence of onabotulinumtoxinA, abobotulinumtoxinA and incobotulinumtoxinA.

Use of AbobotulinumtoxinA for Cosmetic Treatments in the Neck, and Middle and Lower Areas of the Face: A Systematic Review

AbobotulinumtoxinA (aboBoNT-A) has been used for various cosmetic purposes, including minimization of moderate to severe lines, or other cosmetic indications, in the face and neck. We carried out a systematic review to identify all relevant evidence on the treatment approaches and outcomes of aboBoNT-A as a cosmetic treatment of the middle and lower areas of the face, and the neck. Embase, MEDLINE, Cochrane Library, congress proceedings and review bibliographies were searched for relevant studies. Identified articles were screened against pre-specified eligibility criteria. Of 560 unique articles identified, 10 were included for data extraction (three observational studies, 1 randomized controlled trial [with two articles] and five non-randomized trials). The articles provided data on gummy/asymmetric smile (2), marionette lines (5), masseter muscle volume (2), nasal wrinkles (2), perioral wrinkles (3) and the platysma muscle (4). All articles reporting on efficacy of aboBoNT-A demonstrated positive results, including reduction of wrinkles (5), reduction of masseter muscle (2) and degree of gummy smile (1) compared with before treatment. No serious adverse events were reported and patient satisfaction was high. In conclusion, positive findings support further research of aboBoNT-A for the middle and lower areas of the face, and in the neck, which are largely unapproved indications.

Onset and Duration of AbobotulinumtoxinA for Aesthetic Use in the Upper face: A Systematic Literature Review

OBJECTIVE: We sought to analyze the current literature regarding time to onset and duration of effect of abobotulinumtoxinA (aboBoNT-A, Dysport®/Azzalure®) for upper facial aesthetic indications. METHODS: We conducted a systematic review of literature databases (PubMed/MEDLINE, Embase, Cochrane Library, and Google Scholar) to identify English-language publications relevant to: population (patients with aesthetic indications [including glabellar lines and wrinkles]); interventions (aboBoNT-A); comparators (no restrictions); outcomes (efficacy, including onset of action and duration of effect); and settings (clinical). A manual search of review paper bibliographies was performed. Structured data extraction was used to enable interstudy analysis. RESULTS: Overall, 42 original research papers relevant to aboBoNT-A onset and/or duration were identified. All 24 studies assessing efficacy within one week post-injection demonstrated some response at the first time point assessed, and all 37 studies assessing duration showed some response after 12 weeks. Although methodologies for assessing onset and duration differed, when outcomes were refined by reported mean/median, at least 50 percent of patients responding to treatment, or significance versus placebo or baseline at a given time point, onset was most often reported within 2 to 3 days (7 studies), and as early as 24 hours (2 studies). Duration was most often reported as four months (18 studies), although four studies provided evidence that aboBoNT-A efficacy was maintained at five months and three studies at or after six months post-injection. CONCLUSION: This review indicates that aboBoNT-A has a median onset of efficacy of 2 to 3 days and a longer duration of action (3-6 months across studies) than the current labelled minimum treatment interval (12 weeks).

When can maximal efficacy occur with repeat botulinum toxin injection in upper limb spastic paresis?

Repeated injection cycles with abobotulinumtoxinA, a botulinum toxin type A, are recommended in current clinical guidelines as a treatment option for adults with upper limb spastic paresis. However, the magnitude of the maximal therapeutic effect of repeated abobotulinumtoxinA treatment across different efficacy parameters and the number of injection cycles required to reach maximal effect remain to be elucidated. Here, we present a post hoc exploratory analysis of a randomized, double-blind, placebo-controlled trial (12–24 weeks; NCT01313299) and open-label extension study (up to 12 months; NCT0131331), in patients aged 18–80 years with hemiparesis for ≥6 months after stroke/traumatic brain injury. Two inferential methods were used to assess the changes in efficacy parameters after repeat abobotulinumtoxinA treatment cycles: Mixed Model Repeated Measures analysis and Non-Linear Random Coefficients analysis. Using the latter model, the expected maximal effect size (not placebo-controlled) and the number of treatment cycles to reach 90% of this maximal effect were estimated. Treatment responses in terms of passive and perceived parameters (i.e. modified Ashworth scale in primary target muscle group, disability assessment scale for principal target for treatment or limb position, and angle of catch at fast speed) were estimated to reach near-maximal effect in two to three cycles. Near-maximal treatment effect for active parameters (i.e. active range of motion against the resistance of extrinsic finger flexors and active function, assessed by the Modified Frenchay Scale) was estimated to be reached one to two cycles later. In contrast to most parameters, active function showed greater improvements at Week 12 (estimated maximal change from baseline-modified Frenchay Scale overall score: +0.8 (95% confidence interval, 0.6; 1.0) than at Week 4 (+0.6 [95% confidence interval, 0.4; 0.8]). Overall, the analyses suggest that repeated treatment cycles with abobotulinumtoxinA in patients chronically affected with upper limb spastic paresis allow them to relearn how to use the affected arm with now looser antagonists. Future studies should assess active parameters as primary outcome measures over repeated treatment cycles, and assess efficacy at the 12-week time-point of each cycle, as the benefits of abobotulinumtoxinA may be underestimated in the studies of insufficient duration.

Abbreviated summary

In this post hoc analysis of repeated abobotulinumtoxinA injection cycles in upper limb spastic paresis, Gracies et al. used statistical modelling to elucidate the maximal therapeutic effect of abobotulinumtoxinA. Notably, the number of injections required to reach this maximal effect was higher for active (e.g. active function) compared with passive (e.g. tone) parameters.

A Retrospective Cost Analysis of Patients Who Switched from OnabotulinumtoxinA to IncobotulinumtoxinA in a Private Neurology Practice

BACKGROUND

Botulinum neurotoxin type A (BoNT-A) is an effective treatment for many chronic conditions, but the economic implications of repeated treatments can be a burden on patients. The 3 commercial preparations of BoNT-A types available today are onabotulinumtoxinA, abobotulinumtoxinA, and incobotulinumtoxinA, but no clear differences have been found in clinical efficacy between these 3 type A toxins in blinded comparative studies.

OBJECTIVE

To conduct a cost-minimization analysis in a cohort of patients with chronic neurologic conditions who switched treatment from onabotulinumtoxinA to incobotulinumtoxinA.

METHODS

The study was a single-center, retrospective review of data from a large, private, neurological practice in Spokane, WA. A comprehensive patient chart review was conducted of all patients who were switched from established onabotulinumtoxinA therapy to incobotulinumtoxinA therapy between 2012 and 2019. The patients were switched at a 1:1-unit ratio. All patients had commercial insurance or Medicare coverage. Dosage, injection intervals, wastage, treatment costs, switchback data, and patient savings program eligibility were evaluated for the period of 1 year before and 1 year after the switch from onabotulinumtoxinA to incobotulinumtoxinA therapy.

RESULTS

The most frequently treated indication was cervical dystonia (N = 61; 54.5%), followed by chronic migraine (N = 36; 32.1%). After switching to incobotulinumtoxinA therapy, botulinum toxin wastage was reduced by 87.3% (from 150.9 units to 19.1 units), and the cost was reduced by 32.2% (from $5108 to $3461) per patient annually. A total of 14,635 units in unavoidable wastage and $182,792 in annual botulinum toxin costs were saved as a result of the switch in therapy. Patients remained at consistent dosing intervals after switching to incobotulinumtoxinA therapy. A total of 8 patients switched back to onabotulinumtoxinA treatment during this review, including 3 patients who switched back because of insurance reasons, and 5 who had self-reported efficacy concerns. The 70 commercially insured patients in the study who were eligible for the patient savings program for each of the 2 therapies saved an average of $2076 (241.5%) in annual costs after switching from onabotulinumtoxinA to incobotulinumtoxinA.

CONCLUSION

Our findings showed that switching from onabotulinumtoxinA to incobotulinumtoxinA at similar intervals and dosages achieved considerable cost-savings, with a low incidence of switching back.

Duration of Symptom Relief Between Injections for AbobotulinumtoxinA (Dysport®) in Spastic Paresis and Cervical Dystonia: Comparison of Evidence From Clinical Studies

Background: Botulinum toxin-A is a well-established treatment for adult and pediatric spastic paresis and cervical dystonia. While guidelines and approved labels indicate that treatment should not occur more frequently than every 12 weeks, studies and real-world evidence show that the timing of symptom recurrence between treatments may vary. Methods: We report retreatment criteria and response duration (retreatment intervals) from four pivotal, double-blind, placebo-controlled studies with open-label extensions involving patients treated with abobotulinumtoxinA (aboBoNTA) for upper limb (NCT01313299) or lower limb (NCT01249404) spastic paresis in adults, lower limb spastic paresis in children (NCT01249417), and cervical dystonia in adults (NCT00257660). We review results in light of recently available preclinical data. Results: In spastic paresis, 24.0-36.9% of upper limb patients treated with aboBoNTA and 20.1-32.0% of lower limb patients did not require retreatment before 16 weeks. Moreover, 72.8-93.8% of aboBoNTA-treated pediatric patients with lower limb spastic paresis did not require retreatment before 16 weeks (17.7-54.0% did not require retreatment before 28 weeks). In aboBoNTA-treated patients with cervical dystonia, 72.6-81.5% did not require retreatment before 16 weeks. Conclusion: AboBoNTA, when dosed as recommended, offers symptom relief beyond 12 weeks to many patients with spastic paresis and cervical dystonia. From recently available preclinical research, the amount of active neurotoxin administered with aboBoNTA might be a factor in explaining this long duration of response.

Use of AbobotulinumtoxinA in Adults with Cervical Dystonia: A Systematic Literature Review

Cervical dystonia (CD) is a neurological movement disorder characterized by sustained involuntary muscle contractions. First-line therapy for CD is intramuscular injections of botulinum neurotoxin (e.g., abobotulinumtoxinA) into the affected muscles. The objective of this systematic literature review is to assess the clinical evidence regarding the effects of abobotulinumtoxinA for treatment of CD in studies of safety, efficacy, patient-reported outcomes, and economic outcomes. Using comprehensive electronic medical literature databases, a search strategy was developed using a combination of Medical Subject Heading terms and keywords. Results were reviewed by two independent reviewers who rated the level of evidence. The search yielded 263 publications, of which 232 were excluded for being duplicate publications, not meeting the selection criteria, or failing to meet predefined eligibility criteria, leaving a total of 31 articles. Clinical efficacy, patient-reported outcomes, and safety data were in 6 placebo-controlled trials (8 articles), 6 active-controlled trials, and 16 observational studies (17 articles). Data on health economic outcomes were provided in one of the clinical trials, in two of the observational studies, and in one specific cost-analysis publication. This review demonstrated that the routine use of abobotulinumtoxinA in CD is well-established, effective, and generally well-tolerated, with a relatively low cost of treatment.

Abobotulinumtoxina injections in shoulder muscles to improve adult upper limb spasticity: Results from a phase 4 real-world study and a phase 3 open-label trial

Botulinum toxins, such as abobotulinumtoxinA, are used to treat spasticity (muscle overactivity) in arm muscles. Spasticity in shoulder muscles occurs in many patients following a stroke. Shoulder spasticity can be painful and limit limb movement. This paper compares the results from patients who did and those who did not receive abobotulinumtoxinA injections in shoulder muscles (among other arm muscles) in 2 studies. In both studies, the results showed that more patients receiving treatment in shoulder muscles chose pain as a key goal for treatment and had reduced pain following treatment compared with patients not treated in the shoulder. In addition, patients receiving shoulder injections showed further improvement in arm movement compared with those not receiving shoulder injections. Overall, these results suggest that abobotulinumtoxinA treatment in shoulder muscles may improve outcomes for patients with arm spasticity involving the shoulder.

Effectiveness of AbobotulinumtoxinA in Post-stroke Upper Limb Spasticity in Relation to Timing of Treatment

Background: Recent studies of botulinum toxin for post-stroke spasticity indicate potential benefits of early treatment (i. e., first 6 months) in terms of developing hypertonicity, pain and passive function limitations. This non-interventional, longitudinal study aimed to assess the impact of disease duration on the effectiveness of abobotulinumtoxinA treatment for upper limb spasticity. Methods: The early-BIRD study (NCT01840475) was conducted between February 2013 and 2018 in 43 centers across Germany, France, Austria, Netherlands and Switzerland. Adult patients with post-stroke upper limb spasticity undergoing routine abobotulinumtoxinA treatment were followed for up to four treatment cycles. Patients were categorized by time from stroke event to first botulinum toxin-A treatment in the study (as defined by the 1st and 3rd quartiles time distribution) into early-, medium- and late- start groups. We hypothesized that the early-start group would show a larger benefit (decrease) as assessed by the modified Ashworth scale (MAS, primary endpoint) on elbow plus wrist flexors compared with the late-start group. Results: Of the 303 patients enrolled, 292 (96.4%) received ≥1 treatment and 186 (61.4%) received 4 injection cycles and completed the study. Patients in all groups showed a reduction in MAS scores from baseline over the consecutive injection visits (i.e., at end of each cycle). Although reductions in MAS scores descriptively favored the early treatment group, the difference compared to the late group did not reach statistical significance at the last study visit (ANCOVA: difference in adjusted means of 0.15, p = 0.546). Conclusions: In this observational, routine-practice study, patients in all groups displayed a benefit from abobotulinumtoxinA treatment, supporting the effectiveness of treatment for patients at various disease stages. Although the data revealed some trends in favor of early vs. late treatment, we did not find strong evidence for a significant benefit of early vs. late start of treatment in terms of reduction in MAS scores.

AbobotulinumtoxinA and rehabilitation vs rehabilitation alone in post-stroke spasticity: A cost-utility analysis

OBJECTIVE

To investigate costs and quality-adjusted life years of rehabilitation combined with abobotulinumtoxinA (aboBoNT-A) (rehab/aboBoNT-A) vs rehabilitation alone (rehab) in post-stroke spasticity in Italy.

DESIGN

Based on both Italian National Health Service and societal perspectives, a 2-year cost-utility analysis model was performed. Subject/patients: The cost-utility analysis model considered hypothetical patients.

METHODS

The cost-utility analysis model was populated with data concerning demographics, disease severity, healthcare and non-healthcare resource consumption. Data were collected via a questionnaire administered to 3 highly experienced Italian physiatrists (864 out of 930 post-stroke spasticity patients on rehab/aboBoNT-A in total). Costs are expressed in Euro (€) based on the year 2018.

RESULTS

The cost to society (rounded to the nearest whole €) was €22,959 (rehab/aboBoNT-A) vs €11,866 (rehab). Italian National Health Service-funded cost was €7,593 (rehab/aboBoNT-A) vs €1,793 (rehab). Over a period of 2 years rehab/aboBoNT-A outperforms rehab in terms of quality-adjusted life years gained (1.620 vs 1.150). The incremental cost-utility ratio was €12,341 (Italian National Health Service viewpoint) and €23,601 (societal viewpoint). Sensitivity analyses confirmed the robustness of the baseline results.

CONCLUSION

Despite some limitations, the higher number of quality-adjusted life years gained vs rehab and the high probability of reaching a cost-utility ratio lower than the Italian informal acceptability range (€25,000-40,000) make rehab/aboBoNT-A a cost-effective healthcare programme for treating patients with post-stroke spasticity in Italy.

Botulinum toxin: Pharmacology and injectable administration for the treatment of primary hyperhidrosis

Hyperhidrosis is a dermatological condition defined by excessive sweating beyond thermoregulatory needs with significant effects on patients' quality of life. Hyperhidrosis is categorized as primary or secondary: primary hyperhidrosis is mostly focal and idiopathic, whereas secondary hyperhidrosis is commonly generalized and caused by an underlying medical condition or use of medications. Various surgical and nonsurgical therapies exist for primary hyperhidrosis. Although botulinum toxin is one of the deadliest toxins known, when used in small doses, it is one of the most effective therapies for primary hyperhidrosis. Botulinum toxin injections are widely used as a second-line primary hyperhidrosis treatment option once topical treatment strategies have failed. This article provides an overview of the commercially available botulinum toxin formulations and their applications in the treatment of primary hyperhidrosis.

Urodynamic Outcomes in Children after Single and Multiple Injections for Overactive and Low Compliance Neurogenic Bladder Treated with Abobotulinum Toxin A

PURPOSE

Intradetrusor botulinum toxin is an established part of the treatment pathway for pediatric patients with neurogenic bladder. We determined the urodynamic effect of single and multiple administrations of abobotulinum toxin A in pediatric patients with neurogenic bladder, and determined the urodynamic efficacy of abobotulinum toxin A in low compliance vs overactive bladders.

MATERIALS AND METHODS

We conducted a single center retrospective review of all pediatric patients with neurogenic bladder treated with abobotulinum toxin A. Videourodynamic data on cystometric capacity, maximum neurogenic detrusor overactivity pressure and compliance were gathered before and after the first abobotulinum toxin A administration and after the last administration. Patients were divided into low compliance and overactive bladder groups depending on initial videourodynamics findings. Paired t-test was used to compare videourodynamic outcomes before vs after abobotulinum toxin A injection. The Mann-Whitney U test was used to compare bladder groups.

RESULTS

A total of 30 patients were included in the study. Of these patients 15 (50%) received multiple abobotulinum toxin A injections. There were 16 patients (53%) with overactive bladder. Abobotulinum toxin A administration significantly improved cystometric capacity (p <0.0001) and maximum neurogenic detrusor overactivity (p=0.0001). Overall, compliance did not change significantly (p=0.25). There was no significant difference in urodynamic parameters between first and last abobotulinum toxin A injections. Improvement in cystometric capacity (p=0.05) and maximum neurogenic detrusor overactivity (p=0.25) was similar between the low compliance and overactive bladder groups. Compliance significantly improved in the low compliance group vs the overactive bladder group (p=0.016).

CONCLUSIONS

Intradetrusor abobotulinum toxin A improves cystometric capacity and maximum neurogenic detrusor overactivity in pediatric patients with neurogenic bladder. This effect is maintained over multiple injections. Compliance is significantly improved in patients with low compliance bladder vs overactive bladder.

Switching from onabotulinumtoxin-A to abobotulinumtoxin-A in children with cerebral palsy treated for spasticity: A retrospective safety and efficacy evaluation

OBJECTIVES

To determine whether switching from onabotulinumtoxinA to abobotulinumtoxinA in children with cerebral palsy is safe and whether therapeutic efficacy is maintained.

METHODS

This retrospective observational study of routine care included 118 children with cerebral palsy (mean age 81.4 months (standard deviation; SD 38.9)) who had switched from onabotulinumtoxinA to abobotulinumtoxinA injections into their lower extremities due to a change in hospital policy. Analysis was limited to the final onabotulinumtoxinA treatment-cycle prior to switch, and the first abobotulinumtoxinA treatment-cycle following switch. The primary objective was to document the safety and tolerability of switching products. Efficacy endpoints included muscle tone, spasticity, and gait function based on Modified Ashworth Scale (MAS), Tardieu Scale (TS) and Observational Gait Scale (OGS) scores.

RESULTS

Treatment-emergent adverse events were recorded in 41 (34.7%) and 31 (26.3%) patients during the onabotulinumtoxinA and abobotulinumtoxinA treatment cycles, respectively. Treatment-related adverse events were reported in 5 patients in the onabotulinumtoxinA treatment-cycle vs 7 in the abobotulinumtoxinA treatment-cycle (p?=?0.774). Treatment efficacy (4–6 weeks post-treatment) was similar in the onabotulinumtoxinA and abobotulinumtoxinA treatment-cycles for all variables (MAS, TS, OGS).

CONCLUSION

In children with cerebral palsy, switching from onabotulinumtoxinA to abobotulinumtoxinA is safe and generally well-tolerated and therapeutic efficacy is maintained.

Intra-articular botulinum toxin type A for treatment of knee osteoarthritis: Clinical trial

In recent years, there is a growing interest in new medical applications of botulinum toxin, including pain control, osteoarthritis treatment, and wound healing. While clinical applications of botulinum toxin seem promising, existing evidence regarding the therapeutic effects is still inadequate. The aim was to assess the efficacy of a single injection of abobotulinumtoxin A into the knee joint cavity to reduce pain in elderly people. We carried out a single group clinical trial in a University Hospital. Thirty participants (24 women) more than 50 years of age with knee osteoarthritis were included. Diagnosis of osteoarthritis was based on clinical and radiologic findings. We gave a single injection containing 250 units of Dysport (= 100 units of botulinum neurotoxin type A) diluted with 5 ml of normal saline. The primary outcome measure was knee pain. The secondary outcome was the patients' opinion about their knee and associated problems measured with the Knee injury and Osteoarthritis Outcome Score. The outcomes were measured at the baseline and at 4 weeks after the intervention. Within-group comparisons based on the Knee injury and Osteoarthritis Outcome Scores showed favorable results for joint pain and stiffness, sports, severity of symptoms, quality of life, and daily activities (all p-values < 0.001). Also, pain intensity, joint effusion, knee clicking and locking, and flexion-extension scores showed significant beneficial results (all p-values ≤ 0.005). We concluded that botulinum neurotoxin type A is an effective and safe initial treatment of knee osteoarthritis with clear clinical advantages. Patients' satisfaction, minimum adverse effects in addition to single-dose prescription make the toxin as a choice for the first-line therapy of osteoarthritis at least at the short-term in elderly people. The symptom relief increases the patient's compliance and willing to participate in other therapeutic programs. REGISTRATION: Iranian Registry of Clinical Trials (IRCT) website http://www.irct.ir/, a WHO Primary Register setup, with registration code: Irct ID: IRCT20180416039323N1.

Quality of life improvements in patients with cervical dystonia following treatment with a liquid formulation of abobotulinumtoxinA (Dysport® )

BACKGROUND AND PURPOSE

In patients with cervical dystonia, abobotulinumtoxinA solution for injection (ASI) has been shown to be similarly effective to freeze-dried abobotulinumtoxinA in reducing Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) total scores. In this secondary analysis, quality of life data as evaluated with the Cervical Dystonia Impact Profile (CDIP-58) are presented.

METHODS

This was a double-blind, randomized, active and placebo-controlled study followed by an open-label extension (NCT01261611). In the double-blind phase, patients were randomized (3:3:1) to one cycle of ASI 500 U (n = 156), abobotulinumtoxinA 500 U (n = 159) or placebo (n = 54). Following the double-blind phase, all patients received open-label ASI for up to four cycles.

RESULTS

The CDIP-58 total scores were significantly improved at week 4 of the double-blind phase in both the ASI 500 U and abobotulinumtoxinA 500 U groups versus placebo [least squares mean change from baseline of -9.5 (-11.51, -7.45) and -11.2 (-13.2, -9.26) vs. -0.9 (-4.04, 2.14), respectively; both P < 0.0001 vs. placebo]. All CDIP-58 domains contributed to this improvement and benefits were maintained across open-label treatment. Positive correlations were observed between CDIP-58 total score and all three TWSTRS domains (R = 0.42-0.62) and for all CDIP-58 subscales with the TWSTRS total score and domains (R = 0.23-0.60).

CONCLUSIONS

Repeat ASI injections are similarly effective to abobotulinumtoxinA in improving patient-reported outcomes of health-related quality of life. Positive correlations were found between TWSTRS total and domain scores and CDIP-58 total and domain scores.

Early AbobotulinumtoxinA (Dysport®) in Post-Stroke Adult Upper Limb Spasticity: ONTIME Pilot Study

The ONTIME study investigated whether early post-stroke abobotulinumtoxinA injection delays appearance or progression of upper limb spasticity (ULS) symptoms. ONTIME (NCT02321436) was a 28-week, exploratory, double-blind, randomized, placebo-controlled study of abobotulinumtoxinA 500U in patients with ULS (Modified Ashworth Scale [MAS] score ≥ 2) 2–12 weeks post-stroke. Patients were either symptomatic or asymptomatic (only increased MAS) at baseline. Primary efficacy outcome measure: time between injection and visit at which re-injection criteria were met (MAS ≥ 2 and ≥1, sign of symptomatic spasticity: pain, involuntary movements, impaired active or passive function). Forty-two patients were randomized (abobotulinumtoxinA 500U: n = 28; placebo: n = 14) with median 5.86 weeks since stroke. Median time to reach re-injection criteria was significantly longer for abobotulinumtoxinA (156 days) than placebo (32 days; log-rank: p = 0.0176; Wilcoxon: p = 0.0480). Eleven (39.3%) patients receiving abobotulinumtoxinA did not require re-injection for ≥28 weeks versus two (14.3%) in placebo group. In this exploratory study, early abobotulinumtoxinA treatment significantly delayed time to reach re-injection criteria compared with placebo in patients with post-stroke ULS. These findings suggest an optimal time for post-stroke spasticity management and help determine the design and sample sizes for larger confirmatory studies.

Minimal clinically important change in the Toronto Western Spasmodic Torticollis Rating Scale

OBJECTIVES

To characterize the minimal clinically important change (MCIC) after treatment in cervical dystonia patients using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS).

METHODS

Changes in the TWSTRS from an observational study of abobotulinumtoxinA in the routine management of cervical dystonia (NCT01314365) were analyzed using the Patient Global Impression of Change (PGIC) as anchor.

RESULTS

For the overall population (N = 304, baseline TWSTRS-Total score 43.4 ± 19.4), the MCIC for the TWSTRS Total score was -11.9 (95%CI: -13.9, -10.0; p < 0.0001). However, thresholds ranged from -3.2 to -18.0 dependent on baseline severity. TWSTRS-Total scores improved linearly by 3 points for every one-point PGIC increase. There was similar linearity between the graded PGIC categories and TWSTRS subscale scores (severity, disability, and pain).

CONCLUSIONS

A 3-point change is the minimal clinically important change after treatment using TWSTRS as endpoint with higher cutoffs for greater baseline disease severity. For an average trial population (TWSTRS-total: 40-45), a 12-point decrease is clinically meaningful.

Safety and Efficacy of Repeat Open-Label AbobotulinumtoxinA Treatment in Pediatric Cerebral Palsy

This was a prospective, repeat-treatment, open-label study (NCT01251380) of abobotulinumtoxinA for the management of lower limb spasticity in children who had completed a double-blind study. Children (2-17 years) received injections into the gastrocnemius-soleus complex, and other distal and proximal muscles as required (maximum total dose per injection cycle: 30 U/kg or 1000U). A total of 216 of the 241 double-blind patients entered the extension study and 207 received ≥1 open label injection into the gastrocnemius-soleus; 17-24% of patients also had injections into the hamstrings. The most frequent adverse events were related to common childhood infections and the most frequent treatment-related adverse event was injection site pain (n = 10). There was no evidence of a cumulative effect on adverse events. Sustained significant clinical improvements in muscle tone (Modified Ashworth Scale), spasticity (Tardieu Scale), overall clinical benefit (Physicians Global Assessment), and goal attainment (Goal Attainment Scale) were also observed across treatment cycles.

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.

Medium- to long-term outcomes of botulinum toxin A for idiopathic overactive bladder

Botulinum toxin A (BoNT-A) has become an important therapeutic tool in the management of refractory overactive bladder (OAB). Over the last decade, there have been growing numbers of patients receiving repeat injections and these outcomes have begun to be reported in large, high-quality cohorts. This article reviews the current evidence for the medium- to long-term use of BoNT-A in adults with idiopathic detrusor overactivity (IDO) receiving repeat injections. We find that medium-term outcomes are encouraging but long-term outcomes are not as extensively reported. There is high-quality evidence that efficacy following the first injection persists across multiple treatment cycles. There are no additional safety concerns from repeat injections up to six treatment cycles. However, there is a need for further data to confirm the efficacy and safety of BoNT-A beyond the follow-up period in the current literature.

History of Botulinum Toxin Treatment in Movement Disorders

BACKGROUND

The frontiers of clinical medicine constantly expand as a result of the innovative efforts of visionary researchers and keen observations of seasoned clinicians. In medicine, rarely has a therapeutic agent been found efficacious in the management of so many symptoms and in such a relatively short time as botulinum toxin. One of the most notable contributions of botulinum toxin therapy in clinical medicine is in the field of movement disorders.

METHODS

The English literature was searched using the Yale search engine including but not limited to PubMed and Ovid. The search includes articles from January 1 1980 to March 1 2016.

RESULTS

A total of 2055 articles were identified. Of these, 132 met the criteria for this review.

DISCUSSION

This historical review highlights early and seminal contributions that have introduced the application of botulinum toxins in the field of movement disorders and provides evidence-based contributions that have established botulinum toxin as an effective treatment for abnormal movements.

Comparison of different consensuses of BTXA in different countries

The most international dosing guidelines on the use of botulinum toxin type A (BTXA) drugs support a 1:1 dose relationship between OnaBTXA and IncoBTXA and 1:2.5 between OnaBTXA and AboBTXA. However, different facial zones demonstrate different doses conversion ratios. The comparative analysis of nine consensuses on the use of Abo-, Ona-, and IncoBTXA in the United States, Russia, and Europe has been performed. We conducted a review of publications adopting the key words "botulinum toxin consensus," "botulinum toxin guideline." Information search has been carried out primarily in specialized databases (DB). To find the relevant RCTs and guidelines/consensuses, the following databases were used: PubMed and Medline that were screened up to May 2008. Results regarding dose ratios for OnaBTXA:AboBTXA and IncoBTXA:AboBTXA showed that in most cases it is characterized both by increase and by decrease compared to the ratio of 1:2.5. The mean value of dose ratios OnaBTXA:AboBTXA adopted in the United States is 1:2.8. The ratio IncoBTXA:AboBTXA according to international and Russian data is 1:1.9. There are some differences in clinical approach of BTXA use in certain countries. In Russia, low doses are recommended for "crow's feet" and forehead. The US consensus recommends a higher dosage to correct perioral wrinkles. Despite many years of experience in using BTXA, there is no strict international uniformity of clinical guidelines. The recommended doses for the individual areas of the face may differ in different countries. Therefore, physicians in their practice should be guided not by international consensuses, but prefer a national guidelines.

The role of botulinum toxin A in treating neurogenic bladder

Neurogenic detrusor overactivity (NDO) can result in lower and upper urinary tract complications and eventually even in end-stage kidney failure. Since the driving force of this clinical cascade is high bladder pressure, controlling intravesical pressure in NDO patients improves both quality of life and life-expectancy in these patients. Botulinum toxin A (BTX-A) has proven its efficacy in reducing intravesical pressure and in reducing incontinence episodes. BTX-A also improves quality of life in patients with NDO. Both onabotulinumtoxinA (Botox^®, Allergan, Irvine, USA) and abobotulinumtoxinA (Dysport^®, Ipsen, Paris, France) have a level A recommendation for NDO-treatment. The recommended dose for intradetrusor injections in NDO patients is 200 U of onabotulinumtoxinA or 500 U of abobotulinumtoxinA. The drug is generally administered extratrigonal in the detrusor muscle, via cystoscopic guided injection at 20 sites in 1 mL injections. Intradetrusor BTX-A injections are safe, with mostly local complications such as urinary tract infection and high post-void residual or retention. The effect of the toxin lasts for approximately 9 months. Repeat injections can be performed without loss of efficacy. Different injection techniques, novel ways of BTX-A administration, eliminating the need for injection or new BTX-A types with better/longer response rates could change the field in the future.

Safety and efficacy of incobotulinumtoxinA as a potential treatment for poststroke spasticity

Spasticity is a common disabling symptom for several neurological conditions. Botulinum toxin type A injection represents the gold standard treatment for focal spasticity after stroke showing efficacy, reversibility, and low prevalence of complications. In recent years, incobotulinumtoxinA, a new Botulinum toxin type A free of complexing proteins, has been used for treating several movement disorders with safety and efficacy. IncobotulinumtoxinA is currently approved for treating spasticity of the upper limb in stroke survivors, even if several studies described the use also in lower limb muscles. In the present review article, we examine the safety and effectiveness of incobotulinumtoxinA for the treatment of spasticity after stroke.

Does Reduction of Number of Intradetrusor Injection Sites of aboBoNTA (Dysport®) Impact Efficacy and Safety in a Rat Model of Neurogenic Detrusor Overactivity?

Intradetrusor injections of Botulinum toxin A—currently onabotulinumtoxinA—is registered as a second-line treatment to treat neurogenic detrusor overactivity (NDO). The common clinical practice is 30 × 1 mL injections in the detrusor; however, protocols remain variable and standardization is warranted. The effect of reducing the number of injection sites of Dysport^® abobotulinumtoxinA (aboBoNTA) was assessed in the spinal cord-injured rat (SCI). Nineteen days post-spinalization, female rats received intradetrusor injections of saline or aboBoNTA 22.5 U distributed among four or eight sites. Two days after injection, continuous cystometry was performed in conscious rats. Efficacy of aboBoNTA 22.5 U was assessed versus aggregated saline groups on clinically-relevant parameters: maximal pressure, bladder capacity, compliance, voiding efficiency, as well as amplitude, frequency, and volume threshold for nonvoiding contractions (NVC). AboBoNTA 22.5 U significantly decreased maximal pressure, without affecting voiding efficiency. Injected in four sites, aboBoNTA significantly increased bladder capacity and compliance while only the latter when in eight sites. AboBoNTA significantly reduced NVC frequency and amplitude. This preclinical investigation showed similar inhibiting effects of aboBoNTA despite the number of sites reduction. Further studies are warranted to optimize dosing schemes to improve the risk-benefit ratio of BoNTA-based treatment modalities for NDO and further idiopathic overactive bladder.

OnabotulinumtoxinA and AbobotulinumtoxinA Dose Conversion: a Systematic Literature Review

Objective

This systematic review was performed to elucidate dosing practices, dosing conversions, and related outcomes from randomized, controlled trials that directly compared onabotulinumtoxinA (ONA) and abobotulinumtoxinA (ABO) at various dose conversion ratios for therapeutic use in movement disorders.

Methods

A systematic review of three medical literature databases (PubMed, the Cochrane Library, and EMBASE) was performed to identify relevant comparative clinical studies, systematic reviews, and meta‐analyses published in the English language between January 1991 and January 2015. Studies that met predefined inclusion criteria were selected for formal data extraction and quality assessment.

Results

A total of 182 manuscripts were identified, of which four were included for analysis. Targeted clinical applications included neurological disorders. The studies compared ONA to ABO dose conversion ratios of 1:2.5 (n = 1), 1:3 (n = 2), and 1:4 (n = 2). One study compared both 1:3 and 1:4 ratios. An ONA:ABO conversion factor of 1:2.5 was associated with similar efficacy and side effects. An ONA:ABO ratio of 1:3 provided similar or higher efficacy, but an increased rate of adverse effects, and an ONA:ABO ratio of 1:4 was associated with higher efficacy, but with an excessive rate of intolerable side effects.

Conclusion

A dose conversion ratio of ONA to ABO between 1:2.5 and 1:3.0 provides comparable safety and efficacy for therapeutic movement disorders chemodenervation procedures.

Patient considerations in the treatment of cervical dystonia: focus on botulinum toxin type A

Cervical dystonia is the most common form of focal dystonia characterized by involuntary muscle contractions causing abnormal movements and posturing of the head and neck and is associated with significant pain. Botulinum toxin is considered first-line therapy in the treatment of pain and abnormal head posturing associated with cervical dystonia. There are currently three botulinum toxin type A neurotoxins and one botulinum type B neurotoxin commercially available and US Food and Drug Administration (FDA) labeled for the treatment of cervical dystonia. This review will focus on the efficacy, safety, and therapeutic use of botulinum type A neurotoxins in the treatment of cervical dystonia. We conclude with a discussion of factors influencing toxin selection including therapeutic effect, duration of effect, side effect profile, cost, and physician preference.

Clinical resistance to three types of botulinum toxin type A in aesthetic medicine

Botulinum toxin injections have become the most frequent noninvasive cosmetic procedure carried out worldwide. Botulinum toxin has also multiple other indications in different medical fields. However, with the repetition of injections, a new concern has emerged: clinical resistance and loss of effectiveness of the treatment. After reporting a case of primary nonresponsiveness to three types of botulinum toxin type A injections, we conducted a review about all factors leading to the primary or secondary nonresponsiveness, as well as the factors affecting the immunogenicity of this neurotoxin. Most of the reports and studies focused on secondary resistance to botulinum toxin (BT) and the neurotoxin immunogenicity; primary nonresponsiveness was rarely reported. Factors leading to primary or secondary resistance to BT injections were numerous. In the majority of the studies, development of neutralizing antibodies to botulinum toxin was considered responsible of the induced clinical resistance. Patients should be aware of this rising concern as well as clinicians who should learn how to minimize the risk of resistance development, sparing the patients more invasive treatment modalities. Further studies related to botulinum toxin resistance are needed.

Botulinum toxin type A products are not interchangeable: a review of the evidence

Botulinum toxin type A (BoNTA) products are injectable biologic medications derived from Clostridium botulinum bacteria. Several different BoNTA products are marketed in various countries, and they are not interchangeable. Differences between products include manufacturing processes, formulations, and the assay methods used to determine units of biological activity. These differences result in a specific set of interactions between each BoNTA product and the tissue injected. Consequently, the products show differences in their in vivo profiles, including preclinical dose response curves and clinical dosing, efficacy, duration, and safety/adverse events. Most, but not all, published studies document these differences, suggesting that individual BoNTA products act differently depending on experimental and clinical conditions, and these differences may not always be predictable. Differentiation through regulatory approvals provides a measure of confidence in safety and efficacy at the specified doses for each approved indication. Moreover, the products differ in the amount of study to which they have been subjected, as evidenced by the number of publications in the peer-reviewed literature and the quantity and quality of clinical studies. Given that BoNTAs are potent biological products that meet important clinical needs, it is critical to recognize that their dosing and product performance are not interchangeable and each product should be used according to manufacturer guidelines.

Botulinum toxin type A treatment to the upper face: retrospective analysis of daily practice

Background

Botulinum toxin type A treatment has been used for over 20 years to enhance the appearance of the face. There are several commercially available botulinum toxin type A products used in aesthetic clinical practice. The aim of this retrospective analysis was to compare the clinical efficacy of the most commonly used botulinum toxin type A preparations in daily practice.

Methods

Physicians from 21 centers in Germany completed questionnaires based on an inspection of subject files for subjects 18 years of age or over who had received at least two, but not more than three, consecutive treatments with incobotulinumtoxinA, onabotulinumtoxinA, or abobotulinumtoxinA within a 12-month period in the previous 2 years. Data on subject and physician satisfaction, treatment intervals, dosages, and safety were collected from 1256 subjects.

Results

There were no statistically significant differences between incobotulinumtoxinA and onabotulinumtoxinA with respect to physician and subject satisfaction, dosages, and adverse effects experienced. Both botulinum toxin type A preparations were well tolerated and effective in the treatment of upper facial lines. Due to low treatment numbers, abobotulinumtoxinA was not included in the statistical analysis.

Conclusion

The results of this retrospective analysis confirm the results of prospective clinical trials by demonstrating that, in daily practice, incobotulinumtoxinA and onabotulinumtoxinA are used at a 1:1 dose ratio and display comparable efficacy and safety.