A Randomized, Double-Blind Trial to Investigate the Equivalence of IncobotulinumtoxinA and OnabotulinumtoxinA for Glabellar Frown Lines

Assessment of the Efficacy and Durability of IncobotulinumtoxinA in the Treatment of the Upper Face in Adult Women

INTRODUCTION

IncobotulinumtoxinA (Xeomin®) is used in the treatment of dynamic wrinkles and the aesthetic repositioning of facial structures. The duration of its muscular effect typically extends for around 4 months. However, the residual aesthetic benefit can be observed for a longer period. To date, the long-term aesthetic benefit of incobotulinumtoxinA in facial aesthetics has not been systematically evaluated. This study aimed to evaluate longitudinally the duration and aesthetic benefits of incobotulinumtoxinA in the treatment of the upper face in adult women.

METHODS

A quasi-experimental, evaluator-blind, clinical trial involving 28 adult women (30-60 years old) with facial movement lines, undergoing treatment of the upper face with incobotulinumtoxinA by two injectors, following an individualized protocol (ONE21 and glabellar contraction patterns) was performed. Participants were evaluated on the day of the intervention (day 0) and days 30, 120, 180, and 240, and subjected to standardized photographs. The following outcomes were evaluated blindly at each visit: Merz Aesthetics Facial Contraction Scale (MAS), GAIS (Global Aesthetic Improvement Scale), and patient satisfaction. Adverse effects were evaluated at each visit.

RESULTS

Participants ranged in age from 30 to 60 years, 93% were self-declared white, and most of their baseline MAS scores for dynamic lines were moderate and severe. All the parameters presented significative reduction from baseline until day 180. At day 240, the dynamic MAS scores were lower than baseline for forehead lines in 15.4% (95% confidence interval (CI) 0.8-30.0%) of the participants, for glabellar lines in 38.5% (95% CI 18.8-58.1%), and for crow's feet lines in 26.9% (95% CI 9.0-44.8%). Aesthetic improvement compared to baseline was identified in 35% (CI 95% 23‒50%) of the participants at day 240, and 62% (CI 95% 42‒81%) of the sample kept reporting some satisfaction with the procedure.

CONCLUSION

The aesthetic treatment of the upper face with incobotulinumtoxinA demonstrates enduring clinical benefits, and patient satisfaction lasting up to 180 days in most participants. The length of efficacy, which exceeded those reported in the literature, may be attributed to the use of techniques based on individualized assessment such as ONE21 and glabellar patterns of contraction.

Efficacy and Safety of LetibotulinumtoxinA in the Treatment of Moderate and Severe Glabellar Lines in Females 35 to 50 Years of Age: Post Hoc Analyses of the Phase 3 Clinical Study Data

Background

Botulinum toxin type A (BoNT-A) injections continue to be widely used as a common treatment for both males and females. According to a recent survey conducted by the International Society of Plastic Aesthetic Surgeons, the majority of patients receiving these injections are females between the ages 35 and 50.

Objectives

A post hoc analysis was conducted to examine whether there were variances in the effectiveness and safety of letibotulinumtoxinA for treating vertical glabellar lines between the broader female study population and a particularly defined group of female participants aged 35 to 50.

Methods

For this post hoc analysis, data from females aged 35 to 50 were extracted and analyzed from the BLESS III study. In this Phase 3 clinical trial, 355 participants with moderate-to-severe glabella frown lines received either 20 U of letibotulinumtoxinA or a placebo. The study evaluated Glabella Line Severity (GLS) score, treatment onset, duration of effects, time to retreatment, and adverse events. A positive response was determined by achieving a GLS score of 0 or 1, as assessed by both patients and investigators, along with at least a 2-point improvement in GLS score relative to baseline at Week 4 after the injections.

Results

Composite responder rates for patients aged 35 to 50 receiving active treatment were significantly higher than for the remaining female population receiving active treatment at Weeks 1, 2, and 4. Females aged 35 to 50 showed higher rates of GLS improvement of ≥1 at Weeks 1, 2, 4, 8, 12, 16, and 20 compared with the remaining female population receiving active treatment. At Week 4, a higher percentage of females aged 35 to 50 achieved a GLS score of 0 upon maximum frowning compared with the remaining females. Females aged 35 to 50 had a shorter median time to onset of GLS improvement compared with the remaining female population. Safety assessments showed a low incidence of treatment-related adverse events in females aged 35 to 50.

Conclusions

LetibotulinumtoxinA showed significantly higher response rates in females aged 35 to 50 compared with other female patients at Weeks 1, 2, and 4. Response rates remained higher up to Week 16. The treatment demonstrated efficacy and safety in treating vertical glabellar lines in this patient group.

Level of Evidence 2

Tailored Indications for Different Neurotoxins

Background

Minimally invasive procedures have become increasingly popular because they require minimal downtime and are effective for achieving a more youthful appearance. All U.S. Food and Drug Administration-approved neurotoxins are indicated for achieving similar effects, even though they are different in regard to structure, manufacturing technique, and storage requirements. It is agreed upon that each neurotoxin is unique and therefore not interchangeable. The aim of the author is to provide an approach for choosing the optimal toxin in different indications regarding the area of treatment, the age and characteristics of the patient, potential risks, and ultimate goals.

Methods

As the country that the author practices carries onabotulinum (ONA), prabotulinum (PRA), and abobotulinum (ABO) toxin type-A, one of these three toxins was preferred for each category. ABO toxins were preferred in wide areas due to the broader action halo. Typical examples include hyperhidrosis treatment, wide forehead area, and calf slimming. In areas where very precise and targeted treatment is required, PRA and ONA toxins were preferred to limit potential side effects due to wider diffusion. First-time patients were typically treated with PRA toxins for a softer trial periods where as "repeat" patients were successfully treated with ABO toxins.

Results

No toxin is superior to the other in terms of producing effects. Yet, small differences in their properties can allow the plastic surgeon to cater to each patient's needs while yielding the most optimal results.

Conclusions

This study is meant to serve as a guideline for choosing the ideal toxin in different patient settings and indications.

IncobotulinumtoxinA for Glabellar Frown Lines in Chinese Subjects: A Randomized, Double-blind, Active-Controlled Phase-3 Study

This study evaluated the efficacy and safety of IncobotulinumtoxinA 20 U for treatment of glabellar frown lines in Chinese subjects.

Methods

This was a prospective, randomized, double-blind, active-controlled, phase-3 study conducted in China. Subjects with moderate to severe glabellar frown lines at maximum frown were randomized to receive IncobotulinumtoxinA (N = 336) or OnabotulinumtoxinA (N = 167).

Results

For the primary efficacy endpoint at day 30, response rates at maximum frown (score "none" or "mild") on the Merz Aesthetic Scales Glabella Lines - Dynamic were comparable between IncobotulinumtoxinA (92.5%) and OnabotulinumtoxinA (95.1%) per investigator's live rating. Noninferiority of IncobotulinumtoxinA versus OnabotulinumtoxinA was successfully demonstrated, as the two-sided 95% confidence interval of -0.97% to 0.43% for the difference in Merz Aesthetic Scales-based response rates (-0.27%) lay completely above the predefined noninferiority margin of -15%. For the secondary efficacy endpoints assessed at day 30, Merz Aesthetic Scales-based response rates (score "none" or "mild") at maximum frown were similarly comparable between both groups per subject (>85%) and independent review panel (>96%) rating. Per Global Impression of Change Scales, greater than 80% of subjects and greater than 90% of investigators in both groups rated treatment results as at least "much improved" at day 30 compared with baseline. Safety profiles were consistent between groups; IncobotulinumtoxinA was well tolerated, and no new safety concerns were identified in Chinese subjects.

Conclusion

IncobotulinumtoxinA 20 U is safe and effective for treatment of moderate to severe glabellar frown lines at maximum frown in Chinese subjects and is noninferior to OnabotulinumtoxinA 20 U.

Efficacy and Safety of Botulinum Toxin Type A for Treatment of Glabellar Lines: A Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Botulinum toxin type A (BoNT/A) has been used in aesthetic applications worldwide, including glabellar lines. Currently, four BoNT/A preparations were approved for the improvement of moderate-to-severe glabellar lines: onabotulinumtoxinA, abobotulinumtoxinA, incobotulinumtoxinA, and prabotulinumtoxinA. DaxibotulinumtoxinA is a new form of BoNT/A drug that is developed in clinical application. We performed this network meta-analysis (NMA) to assess the efficacy and safety of all these different BoNT/A formulations for treating glabellar lines.

METHODS

The investigators searched randomized controlled trials (RCTs) using the Medical Subject Headings (MeSH) terms "botulinum toxin" and "glabellar lines." We searched the relevant studies in electronic databases as following: PubMed, Elsevier, EMBASE and the Cochrane Library. The end points included the percentage of subjects with a glabellar line severity (GLS) score of none (0) or mild (1), and the percentage of subjects achieving ≥ 1-point and 2-point improvement in glabellar line severity at maximum frown at approximately month 1 by the investigators' assessment.

RESULTS

All formulations of BoNT/A were far superior to placebo in efficacy. DaxibotulinumtoxinA was the only treatment that significantly increased the proportion of subjects achieving ≥ 1 point improvement in GLS score compared with other BoNT/A formulations. Moreover, daxibotulinumtoxinA was ranked the highest for the proportion of subjects achieving ≥ 2-point improvement in GLS score. No significant differences were revealed for the incidence of any adverse events (AEs) that related to treatment or drug among all BoNT/A preparations.

CONCLUSION

The overall results of this NMA suggested that daxibotulinumtoxinA is a new BoNT/A preparation that may be not only more effective but also well-tolerated for the treatment of glabellar lines.

LEVEL OF EVIDENCE I

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A Preclinical Study Comparing the Activity and Potency of OnabotulinumtoxinA and PrabotulinumtoxinA

Objective

The goal of this study was to compare the unit-to-unit biological activity of the vacuum-dried formulation of prabotulinumtoxinA (prabotA) and onabotulinumtoxinA (onabotA) in preclinical assays.

Methods

Reconstituted 100 U vials of prabotA and onabotA were tested in 3 distinct assays: plate-capture light chain activity (PC-LCA), measuringlight chain enzymatic activity after recovery of toxin from reconstituted product using a proprietary toxin capture step; cell-based potency assay (CBPA), measuring the intoxication steps of binding, translocation, and light chain activity (synaptosomal-associated protein 25 [SNAP25] cleavage); and mouse Digit Abduction Score (DAS), evaluating muscle paresis. Each assay tested 3 separate prabotA and onabotA lots on several independent test dates.

Results

Multiple orthogonal assays established that when assessed on a unit-to-unit basis, the biological activity of prabotA is lower than that of onabotA. In the PC-LCA and CBPA assays, onabotA displayed 1.51 ± 0.14-fold higher (mean ± SD) and 1.33 ± 0.07-fold higher (mean of pooled lots ± SEM) activity than prabotA, respectively. Similarly, the mouse DAS data showed that onabotA had 1.4 ± 0.1-fold higher (mean ± SEM) potency than prabotA. Results of all 3 assays demonstrated differences in potency, efficacy, and duration of action between onabotA and prabotA on a unit-to-unit basis.

Conclusion

Preclinical assays established differences in the biological activity of onabotA and prabotA, supporting that the units of biological activity are not interchangeable.

Complications of Cosmetic Botulinum Toxin A Injections to the Upper Face: A Systematic Review and Meta-Analysis

Background

Botulinum toxin A (BoNT-A) injections are a popular non-surgical procedure for facial rejuvenation. Its increase in popularity and utilization is met with limited regulations, potentially posing a significant risk to patient safety and public health.

Objectives

The authors sought to assess the safety profile of cosmetic glabellar and forehead BoNT-A injections and evaluate BoNT-A type on complication rate.

Methods

A systematic search of MEDLINE and EMBASE was performed for studies reporting complications after cosmetic BoNT-A in the glabellar or in the forehead region in the glabellar or in the forehead region. A random effects meta-analysis was carried out to assess complication rate. Where there were sufficient randomized-controlled trials, a network meta-analysis was performed.

Results

Of 556 identified articles, 24 were included in the final quantitative analysis, with 4268 BoNT-A injection sessions and 1234 placebos. Frequently observed treatment-related complications in the BoNT-A intervention group included headache, local skin reactions, and facial neuromuscular symptoms. The overall BoNT-A complication rate was 16%. The odds ratio of developing complications from abobotulinum toxin injections compared with placebo was 1.62 (1.15, 2.27; P > 0.05) and that from onabotulinum toxin injections compared with placebo was 1.34 (0.52, 3.48; P > 0.05). In 30% of the studies, the injectors were doctors, whereas the training status of the practitioner was not reported in the remaining 70%.

Conclusions

Cosmetic BoNT-A injections in the glabellar and forehead region appear to be safe, and most complications are mild and transient. Nevertheless, the literature demonstrates heterogeneous reporting of complications and a lack of consistency of the definition of treatment-related complications.

Level of Evidence: 2

Botulinum toxin type A for facial wrinkles

BACKGROUND

Botulinum toxin type A (BontA) is the most frequent treatment for facial wrinkles, but its effectiveness and safety have not previously been assessed in a Cochrane Review.

OBJECTIVES

To assess the effects of all commercially available botulinum toxin type A products for the treatment of any type of facial wrinkles.

SEARCH METHODS

We searched the following databases up to May 2020: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We also searched five trials registers, and checked the reference lists of included studies for further references to relevant randomised controlled trials (RCTs).

SELECTION CRITERIA

We included RCTs with over 50 participants, comparing BontA versus placebo, other types of BontA, or fillers (hyaluronic acid), for treating facial wrinkles in adults.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Primary outcomes were participant assessment of success and major adverse events (AEs) (eyelid ptosis, eyelid sensory disorder, strabismus). Secondary outcomes included physician assessment of success; proportion of participants with at least one AE and duration of treatment effect. We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

We included 65 RCTs, involving 14,919 randomised participants. Most participants were female, aged 18 to 65 years. All participants were outpatients (private office or day clinic). Study duration was between one week and one year. No studies were assessed as low risk of bias in all domains; the overall risk of bias was unclear for most studies. The most common comparator was placebo (36 studies). An active control was used in 19 studies. There were eight dose-ranging studies of onabotulinumtoxinA, and a small number of studies compared against fillers. Treatment was given in one cycle (54 studies), two cycles (three studies), or three or more cycles (eight studies). The treated regions were glabella (43 studies), crow's feet (seven studies), forehead (two studies), perioral (two studies), full face (one study), or more than two regions (nine studies). Most studies analysed moderate to severe wrinkles; mean duration of treatment was 20 weeks. The following results summarise the main comparisons, based on studies of one treatment cycle for the glabella. AEs were collected over the duration of these studies (over four to 24 weeks). Compared to placebo, onabotulinumtoxinA-20 U probably has a higher success rate when assessed by participants (risk ratio (RR) 19.45, 95% confidence interval (CI) 8.60 to 43.99; 575 participants; 4 studies; moderate-certainty evidence) or physicians (RR 17.10, 95% CI 10.07 to 29.05; 1339 participants; 7 studies; moderate-certainty evidence) at week four. Major AEs are probably higher with onabotulinumtoxinA-20 U (Peto OR 3.62, 95% CI 1.50 to 8.74; 1390 participants; 8 studies; moderate-certainty evidence), but there may be no difference in any AEs (RR 1.14, 95% CI 0.89 to 1.45; 1388 participants; 8 studies; low-certainty evidence). Compared to placebo, abobotulinumtoxinA-50 U has a higher participant-assessed success rate at week four (RR 21.22, 95% CI 7.40 to 60.56; 915 participants; 6 studies; high-certainty evidence); and probably has a higher physician-assessed success rate (RR 14.93, 95% CI 8.09 to 27.55; 1059 participants; 7 studies; moderate-certainty evidence). There are probably more major AEs with abobotulinumtoxinA-50 U (Peto OR 3.36, 95% CI 0.88 to 12.87; 1294 participants; 7 studies; moderate-certainty evidence). Any AE may be more common with abobotulinumtoxinA-50 U (RR 1.25, 95% CI 1.05 to 1.49; 1471 participants; 8 studies; low-certainty evidence). Compared to placebo, incobotulinumtoxinA-20 U probably has a higher participant-assessed success rate at week four (RR 66.57, 95% CI 13.50 to 328.28; 547 participants; 2 studies; moderate-certainty evidence), and physician-assessed success rate (RR 134.62, 95% CI 19.05 to 951.45; 547 participants; 2 studies; moderate-certainty evidence). Major AEs were not observed (547 participants; 2 studies; moderate-certainty evidence). There may be no difference between groups in any AEs (RR 1.17, 95% CI 0.90 to 1.53; 547 participants; 2 studies; low-certainty evidence). AbobotulinumtoxinA-50 U is no different to onabotulinumtoxinA-20 U in participant-assessed success rate (RR 1.00, 95% CI 0.92 to 1.08, 388 participants, 1 study, high-certainty evidence) and physician-assessed success rate (RR 1.01, 95% CI 0.95 to 1.06; 388 participants; 1 study; high-certainty evidence) at week four. Major AEs are probably more likely in the abobotulinumtoxinA-50 U group than the onabotulinumtoxinA-20 U group (Peto OR 2.65, 95% CI 0.77 to 9.09; 433 participants; 1 study; moderate-certainty evidence). There is probably no difference in any AE (RR 1.02, 95% CI 0.67 to 1.54; 492 participants; 2 studies; moderate-certainty evidence). IncobotulinumtoxinA-24 U may be no different to onabotulinumtoxinA-24 U in physician-assessed success rate at week four (RR 1.01, 95% CI 0.96 to 1.05; 381 participants; 1 study; low-certainty evidence) (participant assessment was not measured). One participant reported ptosis with onabotulinumtoxinA, but we are uncertain of the risk of AEs (Peto OR 0.02, 95% CI 0.00 to 1.77; 381 participants; 1 study; very low-certainty evidence). Compared to placebo, daxibotulinumtoxinA-40 U probably has a higher participant-assessed success rate (RR 21.10, 95% CI 11.31 to 39.34; 683 participants; 2 studies; moderate-certainty evidence) and physician-assessed success rate (RR 23.40, 95% CI 12.56 to 43.61; 683 participants; 2 studies; moderate-certainty evidence) at week four. Major AEs were not observed (716 participants; 2 studies; moderate-certainty evidence). There may be an increase in any AE with daxibotulinumtoxinA compared to placebo (RR 2.23, 95% CI 1.46 to 3.40; 716 participants; 2 studies; moderate-certainty evidence). Major AEs reported were mainly ptosis; BontA is also known to carry a risk of strabismus or eyelid sensory disorders.

AUTHORS' CONCLUSIONS

BontA treatment reduces wrinkles within four weeks of treatment, but probably increases risk of ptosis. We found several heterogeneous studies (different types or doses of BontA, number of cycles, and different facial regions) hindering meta-analyses. The certainty of the evidence for effectiveness outcomes was high, low or moderate; for AEs, very low to moderate. Future RCTs should compare the most common BontA (onabotulinumtoxinA, abobotulinumtoxinA, incobotulinumtoxinA, daxibotulinumtoxinA, prabotulinumtoxinA) and evaluate long-term outcomes. There is a lack of evidence about the effects of multiple cycles of BontA, frequency of major AEs, duration of effect, efficacy of recently-approved BontA and comparisons with other treatments.

Complications and Adverse Effects of Periocular Aesthetic Treatments

The popularity and variety of temporary and permanent periocular aesthetic treatments has increased over the past decade. Patients frequently present to eye clinics with ocular complications and side effects following these treatments, their severity ranging from ocular irritation from dry eyes to visual loss from vascular occlusion. A careful, thorough history is essential, as many patients may not associate aesthetic procedures with ocular complications, and some may be embarrassed to disclose this information. All ophthalmologists should understand the potential ocular sequelae of these treatments and be able to initiate treatment in sight-threatening cases. Wesummarises the current literature on ophthalmic complications of the most common periocular aesthetic treatments.

Comparative Pharmacodynamics Study of 3 Different Botulinum Toxin Type A Preparations in Mice

A new complexing protein-free botulinum toxin Type A (CBoNT) with the same mechanism of action as the botulinum toxin complex onabotulinumtoxinA (OBoNT) and complexing protein-free incobotulinumtoxinA (IBoNT) was recently developed.

Switchover study of onabotulinumtoxinA to incobotulinumtoxinA for facial dystonia

IMPORTANCE

When making a cost-saving it is important to ensure there is no loss of efficacy.

BACKGROUND

Clinical effectiveness and efficiency of incobotulinumtoxinA compared to onabotulinumtoxinA in facial dystonia is unclear. Our aim is to evaluate switching from onabotulinumtoxinA to incobotulinumtoxinA in the treatment of essential blepharospasm (EB), hemifacial spasm (HFS) and aberrant facial nerve regeneration (AFR).

DESIGN

A retrospective study of a prospective, single-masked switchover audit from onabotulinumtoxinA to incobotulinumtoxinA.

PARTICIPANTS

Twenty essential EB, 12 HFS and six AFR patients.

METHODS

A switchover from stable onabotulinumtoxinA to incobotulinumtoxinA using a 1:1 unit ratio and contemporaneous efficacy measures. Two nurse injectors performed the injections over a period of 6 years. Each masked patient received three onabotulinumtoxinA and three incobotulinumtoxinA over a minimum of 2 years.

MAIN OUTCOME METHODS

At each visit, a blepharospasm disability score (BDS), Jankovic score (JS), subjective improvement (SI), duration of maximum effect (DME) and complications were recorded. A cost comparison per unit dose was made.

RESULTS

Twenty EB, 12 HFS and six AFR received 114 onabotulinumtoxinA and 114 incobotulinumtoxinA treatments. Both brands had similar efficacy, but SI (P < .01) and DME (P < .05) were higher in the HFS group with incobotulinumtoxinA. Complications included bruising (two onabotulinumtoxinA, one incobotulinumtoxinA) and ptosis (three onabotulinumtoxinA, zero incobotulinumtoxinA). OnabotulinumtoxinA was 33% pricier.

CONCLUSION AND RELEVANCE

Switching from onabotulinumtoxinA to incobotulinumtoxinA did not result in an inferior outcome for the treatment of facial dystonia and led to a cost-saving for the department.

OnabotulinumtoxinA Displays Greater Biological Activity Compared to IncobotulinumtoxinA, Demonstrating Non-Interchangeability in Both In Vitro and In Vivo Assays

Differences in botulinum neurotoxin manufacturing, formulation, and potency evaluation can impact dose and biological activity, which ultimately affect duration of action. The potency of different labeled vials of incobotulinumtoxinA (Xeomin^®; 50 U, 100 U, or 200 U vials; incobotA) versus onabotulinumtoxinA (BOTOX^®; 100 U vial; onabotA) were compared on a unit-to-unit basis to assess biological activity using in vitro (light-chain activity high-performance liquid chromatography (LCA-HPLC) and cell-based potency assay (CBPA)) and in vivo (rat compound muscle action potential (CMAP) and mouse digit abduction score (DAS)) assays. Using LCA-HPLC, incobotA units displayed approximately 54% of the protease activity of label-stated equivalent onabotA units. Lower potency, reflected by higher EC₅₀, ID₅₀, and ED₅₀ values (pooled mean ± SEM), was displayed by incobotA compared to onabotA in the CBPA (EC₅₀: incobotA 7.6 ± 0.7 U/mL; onabotA 5.9 ± 0.5 U/mL), CMAP (ID₅₀: incobotA 0.078 ± 0.005 U/rat; onabotA 0.053 ± 0.004 U/rat), and DAS (ED₅₀: incobotA 14.2 ± 0.5 U/kg; onabotA 8.7 ± 0.3 U/kg) assays. Lastly, in the DAS assay, onabotA had a longer duration of action compared to incobotA when dosed at label-stated equivalent units. In summary, onabotA consistently displayed greater biological activity than incobotA in two in vitro and two in vivo assays. Differences in the assay results do not support dose interchangeability between the two products.

IncobotulinumtoxinA Efficacy and Safety in Adults with Upper-Limb Spasticity Following Stroke: Results from the Open-Label Extension Period of a Phase 3 Study

Introduction

The objective of the study was to investigate the efficacy and safety of repeated incobotulinumtoxinA injections for the treatment of upper-limb post-stroke spasticity in adults.

Methods

Adults 18–80 years of age with post-stroke upper-limb spasticity who completed the 12-week randomized, double-blind, placebo-controlled main period (MP) of a phase 3 trial (NCT01392300) were eligible to enrol in the 36-week open-label extension period (OLEX). The OLEX included three treatment cycles at fixed 12-week injection intervals; subjects were injected with 400 U incobotulinumtoxinA into the affected upper limb. Efficacy assessments included evaluation of muscle tone using the Ashworth Scale (AS) and the Global Impression of Change Scale (GICS) assessed by the investigator, subject, and caregiver. The incidence of adverse events (AEs) was monitored throughout the OLEX.

Results

A total of 296 of 299 subjects (99.0%) who completed the MP received incobotulinumtoxinA in the OLEX, and 248 subjects completed the 36-week OLEX. The proportion of subjects with at least a 1-point improvement in AS score from each incobotulinumtoxinA treatment to the respective 4-week post-injection visit ranged by cycle from 52.3% to 59.2% for wrist flexors, 49.1% to 52.3% for elbow flexors, 59.8% to 64.5% for finger flexors, 35.5% to 41.2% for thumb flexors, and 37.4% to 39.9% for forearm pronators (P < 0.0001 for all). Over 90% of subjects were assessed by the investigator to be at least minimally improved (4 weeks post-injection) on the GICS during each injection cycle; 61.0% in the 1st cycle, 58.2% in the 2nd cycle, and 57.4% in the 3rd cycle were considered much improved or very much improved on the GICS. Three percent of subjects (9/296) reported treatment-related AEs; the most frequently reported were pain in the extremity (n = 2, 0.7%) and constipation (n = 2, 0.7%). Serious AEs were reported by 22 subjects (7.4%); however, none were considered treatment-related.

Conclusions

Repeated injections of incobotulinumtoxinA for the treatment of post-stroke upper-limb spasticity led to significant improvements in muscle tone and investigator’s global impression of change. Treatment was well tolerated, with no serious treatment-related AEs.

Funding

Merz Pharmaceuticals GmbH.

Botulinum Toxin Type A Overdoses: Analysis of the FDA Adverse Event Reporting System Database

INTRODUCTION

Published literature on overdoses related to botulinum toxin A (BtxA) agents is scarce.

OBJECTIVE

The aim of this study was to assess the BtxA drug class' respective agents for associations with overdose.

METHODS

United States Food and Drug Administration (FDA) adverse event reporting system (FAERS) database was utilized to search for overdoses. The analysis was conducted on data between second quarter 2014 and third quarter 2017. BtxA cases were included when they were considered the "Primary Suspect" drug. Overdose was defined as presence of 'overdose' being reported as an adverse event. Primary outcome was incidence of 'overdose' compared within the respective agents. Additionally, a disproportionality analysis was conducted utilizing reporting odds ratio (ROR) versus onabotulinumtoxinA as a referent while controlling for confounding variables.

RESULTS

A total of 3,837,406 unique adverse events were reported during the study period for all drugs in the FAERS database. Of which, 13,078 were BtxA cases. The rate of adverse events involving overdose for abobotulinumtoxinA (20.2%; 215/1065) was significantly higher than both onabotulinumtoxinA (0.4%; 48/11,323; p < 0.0001) and incobotulinumtoxinA (0.1%; 1/690; p < 0.0001). In the regression analysis, abobotulinumtoxinA (ROR 73.26; 95% CI 51.17-104.90) had a significant association with overdose, whereas incobotulinumtoxinA (ROR 0.73; 95% CI 0.10-5.36) did not, versus the referent onabotulinumtoxinA.

CONCLUSION

The present analysis showed adverse events of abobotulinumtoxinA were significantly associated with overdose versus the other two BtxA agents. Overdose can be difficult to research, particularly for in-clinic administered drugs. Future studies should venture to confirm these results in new and novel ways.

Botulinum neurotoxin formulations: overcoming the confusion

Botulinum toxin A is produced by anaerobic spore-forming bacteria and is used for various therapeutic and cosmetic purposes. Botulinum toxin A injections are the most popular nonsurgical procedure worldwide. Despite an increased demand for botulinum toxin A injections, the clinical pharmacology and differences in formulation of commonly available products are poorly understood. The various products available in the market are unique and vary in terms of units, chemical properties, biological activities, and weight, and are therefore not interchangeable. For safe clinical practice and to achieve optimal results, the practitioners need to understand the clinical issues of potency, conversion ratio, and safety issues (toxin spread and immunogenicity). In this paper, the basic clinical pharmacology of botulinum toxin A and differences between onabotulinum toxin A, abobotulinum toxin A, and incobotulinum toxin A are discussed.

Safety of IncobotulinumtoxinA in the Treatment of Facial Lines: Results From a Pooled Analysis of Randomized, Prospective, Controlled Clinical Studies

BACKGROUND

The safety and efficacy of incobotulinumtoxinA in aesthetics has been established in multiple studies. Although individual studies have been reported, a combined assessment of incobotulinumtoxinA safety across studies is not available.

OBJECTIVE

To assess the frequency of adverse events (AEs) across prospective incobotulinumtoxinA studies in aesthetics.

MATERIALS AND METHODS

Safety data were assessed from 9 placebo-controlled or active-controlled single-dose studies on glabellar frown lines (GFL), crow's feet (CF), and upper facial lines (UFL). Analyses by treatment cycle included 4 repeat-dose studies on GFL and UFL.

RESULTS

One thousand three hundred seventy-seven subjects received incobotulinumtoxinA (GFL, n = 1,189; CF, n = 83; UFL, n = 105) in single-dose studies (placebo-controlled studies: incobotulinumtoxinA, n = 866; placebo, n = 395). Over 1,000 subjects received incobotulinumtoxinA in repeat-dose studies (GFL, n = 880; UFL, n = 290). In placebo-controlled single-dose studies, incidences of treatment-related AEs ranged from 5.4% (GFL) to 22.9% (UFL). The most frequent treatment-related AE in single-dose studies was headache (GFL, 4.8%; UFL, 11.4%). In repeat-dose studies, incidence of AEs was highest during cycle 1 (GFL, 8.9%; UFL, 17.2%) and decreased across treatment cycles. No serious treatment-related AEs were observed.

CONCLUSION

Results confirm the favorable safety and tolerability of incobotulinumtoxinA. The frequency of treatment-related AEs was low and may decrease with subsequent treatments.

Neurophysiological Measures of Efficacy and Safety for Botulinum Toxin Injection in Facial and Bulbar Muscles: Special Considerations

Botulinum toxin (BoNT) injections into facial and bulbar muscles are widely and increasingly used as medical treatments for cervical and facial dystonia, facial hemispasm, correction of facial palsy, hyperhidrosis, as well as cosmetic treatment of glabellar lines associated with grief and anger. Although BoNT treatment is generally considered safe, the diffusion of the toxin to surrounding muscles may result in complications, including difficulties swallowing, in a dose-dependent manner. The sensitivity of clinical examination for detecting adverse events after BoNT treatment is limited. Few reports have highlighted the potential effects on other muscles in the facial area due to the spreading of the toxin. The possibilities of spreading and thus unknown pharmacological BoNT effects in non-targeted muscles emphasise the importance of correct administration of BoNT in terms of dose selection, injection points, and appropriate effect surveillance. In this review article, we will focus on novel objective measures of efficacy and safety regarding BoNT treatment of facial muscles and the reasons why this is important.

Efficacy of IncobotulinumtoxinA for the Treatment of Glabellar Frown Lines in Male Subjects: Post-Hoc Analyses From Randomized, Double-Blind Pivotal Studies

BACKGROUND

Males are increasingly seeking minimally invasive cosmetic procedures such as botulinum toxin injection. However, few studies have specifically examined the efficacy of such procedures among men.

OBJECTIVE

To assess the efficacy of incobotulinumtoxinA for treating glabellar frown lines (GFLs) in men.

METHODS

Three incobotulinumtoxinA studies were included in post hoc analyses of responder rates: 2 pivotal Phase 3 US registration studies for GFLs (n = 55 males in a pooled analysis) and a European pivotal Phase 3 study for upper facial lines (UFLs; n = 21 males).

RESULTS

In the pooled analysis of Phase 3 GFL studies, 55.9% of males and 81.4% of females were responders on the Facial Wrinkle Scale (FWS) at 30 days. Similarly, 54.5% and 88.0% of males and females, respectively, treated for GFLs in the upper facial line study were responders on the Merz Aesthetics Scales (MAS) at 30 days. Lower proportions of male responders on the Facial Wrinkle Scale /Merz Aesthetics Scales were consistent with results from onabotulinumtoxinA and abobotulinumtoxinA GFL studies.

CONCLUSION

Compared with females, males demonstrate lower response rates on wrinkle severity scales in studies on all 3 available botulinum toxins. Variations in treatment response are potentially associated with key male anatomic differences (e.g., muscle mass). Results emphasize the need for customized treatment plans.

Tailored botulinum toxin type A injections in aesthetic medicine: consensus panel recommendations for treating the forehead based on individual facial anatomy and muscle tone

BACKGROUND

Facial lines and wrinkles are strongly influenced by individual differences in anatomy and muscle activity and no single injection protocol will suit all patients. However, there is only limited information in the published literature on how to develop a tailored approach to botulinum toxin treatment.

METHODS

An expert panel of physicians was convened to establish a consensus on developing an individualized approach to treatment of the forehead with incobotulinumtoxinA. Separate treatment protocols were developed for men and women and subdivided by background level of muscle activity: kinetic, hyperkinetic, and hypertonic. Each muscle tone category was then further subdivided to take account of individual characteristics that can influence treatment.

RESULTS

Consensus members describe how to perform a dynamic assessment to optimize the dose and injection technique for each patient. A tailored treatment protocol is described for men and women with a wide range of forehead presentations. For each presentation, units of toxin as well as the precise location of injection points were defined by creating a 12-zone map of the forehead.

CONCLUSION

These recommendations depart from traditional consensus documents by providing detailed incobotulinumtoxinA injection protocols for the forehead based on the major parameters that differ between patients, including muscular anatomy, size, and tone. It is expected that the use of this document will lead to more satisfactory, natural, and individualized aesthetic outcomes for patients.

Efficacy and Tolerability of IncobotulinumtoxinA for Treating Glabellar Frown Lines in Korean Adults: A Postmarketing Observational Study

BACKGROUND

IncobotulinumtoxinA is safe and effective in Caucasian adults. Its effects have been less documented in Asian adults.

OBJECTIVE

To describe the efficacy and tolerability of incobotulinumtoxinA for treating glabellar frown lines (GFLs) in South Korean adults.

METHODS

South Korean adults aged 18 to 65 years with moderate-to-severe GFLs received a single dose of 10 to 28 U incobotulinumtoxinA during routine clinical practice. After 30 ± 14 days, investigators assessed the efficacy using the Global Aesthetic Improvement Scale and rated tolerability using a 4-point scale.

RESULTS

Six hundred seventy-three subjects were enrolled, of which 528 completed the study according to protocol. Glabellar frown lines improved in 98.7% (521/528) of subjects, with 30.8% of cases rated as "very much improved" and 47.4% as "much improved." The extent of improvement was unaffected by sex, age, and weight but was greater when the time between GFL identification and treatment was <6 months (p < .001) and when concomitant aesthetic nondrug treatments were used (p < .001). For 94% of subjects, tolerability was good or very good. All reported adverse events were transient and mild or moderate in severity.

CONCLUSION

IncobotulinumtoxinA was well tolerated and effective for treating moderate-to-severe GFLs in Korean adults irrespective of age, sex, or weight.

IncobotulinumtoxinA for Aesthetic Indications: A Systematic Review of Prospective Comparative Trials

BACKGROUND

IncobotulinumtoxinA is a botulinum toxin type A (BoNTA) indicated for temporary improvement in the appearance of upper facial lines with well-established efficacy and safety profiles. Whether incobotulinumtoxinA and other BoNTAs are equipotent is subject of debate.

OBJECTIVE

To compare the efficacy of incobotulinumtoxinA and other BoNTAs for aesthetic applications.

MATERIALS AND METHODS

PubMed and Embase were systematically searched for prospective clinical trials comparing incobotulinumtoxinA with onabotulinumtoxinA, abobotulinumtoxinA, or placebo for aesthetic applications.

RESULTS

Fifteen articles met the selection criteria. Two studies found that incobotulinumtoxinA was noninferior or equivalent to onabotulinumtoxinA for the treatment of glabellar frown lines (GFLs). Eight studies found no difference in efficacy between incobotulinumtoxinA and other BoNTAs. One study suggested differences in response rates at certain time points between incobotulinumtoxinA and onabotulinumtoxinA for GFLs, and one suggested differences for dynamic horizontal forehead lines but not for GFLs or lateral periorbital lines, but both had study design issues limiting the ability to draw conclusions. Finally, 3 placebo-controlled studies demonstrated the efficacy of incobotulinumtoxinA for treating GFLs and upper facial lines.

CONCLUSION

The weight of the evidence from comparative clinical trials indicates that incobotulinumtoxinA, onabotulinumtoxinA, and abobotulinumtoxinA have similar efficacy for aesthetic applications.

AbobotulinumtoxinA: A 25-Year History

During the late 1960s and early 1970s, Alan Scott showed that intramuscular injections of botulinum toxin (BoNT) corrected nonaccommodative strabismus without resorting to surgery. The UK doctors who trained with Scott soon realized the significant potential offered by BoNT type A as a therapeutic option for several difficult-to-treat diseases. This led to a collaboration between these pioneering clinicians and the Centre for Applied Microbiology and Research at Porton Down, United Kingdom, and, in turn, to the development and commercialization of abobotulinumtoxinA as Dysport (Dystonia/Porton Down; Ipsen Biopharm Ltd., Wrexham, UK). Dysport was approved in Europe for the treatment of specific dystonias in December 1990 and now has marketing authorizations in 75 countries. Since then, the use of BoNT in therapeutic and aesthetic indications has grown year-on-year, and continues to expand well beyond Scott's initial aim. For example, ongoing trials are assessing potential new indications for BoNT-A, including acne and psoriasis. Furthermore, a growing number of other BoNT products, often termed "biosimilars," together with innovative formulations of well-established BoNT types, are likely to reach the market over the next few years. This review focuses on the history of Dysport to mark the 25th anniversary of its first launch in the United Kingdom.

The Practical Use of AbobotulinumtoxinA in Aesthetics

Botulinum toxin (BoNT) has been approved for aesthetic use since 2002. Since then, clinical studies and expert use have informed our understanding of how BoNT exerts its clinical effect and the practical use of this product across a number of aesthetic applications. This review discusses the clinical properties and characteristics of abobotulinumtoxinA, which patients are suitable for its use, and how it can be utilized to treat facial rhytides.