Botulinum neurotoxin type A in the interdisciplinary treatment of sialorrhea in adults and children-update and practice recommendations

Sialorrhea is defined as a chronic excessive flow of saliva from the mouth, often with adverse consequences for health and quality of life of patients. In addition to currently used non-drug treatment and systemic drugs, intraglandular Botulinum Neurotoxin A (BoNT/A) injections have been examined in case studies, controlled trials and clinical practice. Two pivotal Phase III trials recently led to market approval in the USA and EU for IncobotulinumtoxinA [Xeomin®, IncoBoNT/A, Clostridium botulinum neurotoxin type A (150 kD), free from complexing proteins, Merz Pharmaceuticals GmbH] for treatment of chronic sialorrhea in adults and pediatric patients. This review provides a multidisciplinary approach to discuss the current state of sialorrhea therapy as well as benefits and current limitations of BoNT/A injections. A consensus regarding treatment recommendations made available to physicians in Germany in 2022 has now been updated here for presentation to an international audience. This review provides a framework including a flow chart for patient selection, recommendations for dosing and the injection process, as well as a discussion of therapeutic goals, long-term benefits and safety aspects. This review is aimed at supporting physicians in developing multidisciplinary and individualized treatment approaches to achieve optimal benefits for patients.

Neuromodulators for Skin

Neurotoxins are the most popular nonsurgical aesthetic procedure for men and women of all ages. Five botulinum toxin A (BoNTA) products represent the current palette of available BoNTA for cosmetic use. Off-label uses of BoNTA continue to expand and are now used for skin rejuvenation, to treat various skin disorders, and in facial nerve paralysis. Dermal and subdermal injections of dilute BoNTA has grown in popularity and been shown to improve skin texture and quality. Common targets for chemodenervation in facial nerve synkinesis are ipsilateral orbicularis oculi, mentalis, depressor anguli oris, buccinator, corrugator muscles, and the ipsilateral and/or contralateral frontalis.

Botulinum toxin A (IncobotulinumtoxinA) and pneumoperitoneum image-guided for hernia repair with loss of dominance

Post-incisional ventral hernia is estimated at 5-30%, when the content of the abdominal cavity migrates to the hernial sac (HSV), with a HSV/abdominal cavity volume ratio > 25%, conditioning systemic changes defined as "loss of domain". A 27-year-old male presented with ventral hernia with loss of domain that required pre-operative preparation techniques, using application of botulinum toxin A (IncobotulinumtoxinA) and pneumoperitoneum, both guided by image. A ventral plasty was performed with adequate return of the viscera to the abdominal cavity. The combination of both techniques seems to be a safe procedure to carry out a tension-free repair.

Significantly lower antigenicity of incobotulinumtoxin than abo- or onabotulinumtoxin

BACKGROUND

For many indications, BoNT/A is repetitively injected with the risk of developing neutralizing antibodies (NABs). Therefore, it is important to analyze whether there is a difference in antigenicity between the different licensed BoNT/A preparations.

METHODS

In this cross-sectional study, the prevalence of NABs was tested by means of the sensitive mouse hemidiaphragm assay (MHDA) in 645 patients. Patients were split into those having exclusively been treated with the complex protein-free incoBoNT/A preparation (CF-MON group) and those having started BoNT/A therapy with a complex protein-containing BoNT/A preparation (CC-I group). This CC-I group was split into those patients who remained either on abo- or onaBoNT/A (CC-MON group) and those who had been treated with at least two BoNT/A preparations (CC-SWI group). To balance treatment duration, only CC-MON patients who did not start their BoNT/A therapy more than 10 years before recruitment (CC-MON-10 group) were further analyzed. The log-rank test was used to compare the prevalence of NABs in the CF-MON and CC-MON-10 group.

RESULTS

In the CF-MON subgroup, no patient developed NABs. In the CC-I group, 84 patients were NAB-positive. NABs were found in 33.3% of those who switched preparations (CC-SWI) and in 5.9% of the CC-MON-10 group. Kaplan-Meier curves for remaining NAB-negative under continuous BoNT/A therapy were significantly different (p < 0.035) between the CF-MON and CC-MON-10 group.

CONCLUSION

Frequent injections of a complex protein-containing BoNT/A preparation are associated with significantly higher risks of developing NABs than injections with the same frequency using the complex protein-free incoBoNT/A preparation.

IncobotulinumtoxinA Efficacy/Safety in Upper-Limb Spasticity in Pediatric Cerebral Palsy: Randomized Controlled Trial

BACKGROUND

This randomized phase 3 study with double-blind main period (MP) and open-label extension (OLEX; NCT02002884) assessed incobotulinumtoxinA safety and efficacy for pediatric upper-limb spasticity treatment in ambulant/nonambulant (Gross Motor Function Classification System [GMFCS] I-V) patients, with the option of combined upper- and lower-limb treatment.

METHODS

Patients were aged two to 17 years with unilateral or bilateral spastic cerebral palsy (CP) and Ashworth Scale (AS) score ≥2 in treatment-selected clinical patterns. In the MP, patients were randomized (2:1:1) to incobotulinumtoxinA 8, 6, or 2 U/kg body weight (maximum 200, 150, 50 U/upper limb), with optional lower-limb injections in one of five topographical distributions (total body dose ≤16 to 20 U/kg, maximum 400 to 500 U, depending on body weight and GMFCS level). In the OLEX, patients received three further treatment cycles, at the highest MP doses (8 U/kg/upper limb group). Outcomes included AS, Global Impression of Change Scale (GICS), and adverse events (AEs).

RESULTS

AS scores improved from baseline to week 4 in all MP dose groups (n = 350); patients in the incobotulinumtoxinA 8 U/kg group had significantly greater spasticity improvements versus the 2 U/kg group (least-squares mean [standard error] for upper-limb main clinical target pattern -1.15 [0.06] versus -0.93 [0.08]; P = 0.017). Investigator's, child/adolescent's, and parent/caregiver's GICS scores showed improvements in all groups. Treatment benefits were sustained over further treatment cycles. AE incidence did not increase with dose or repeated treatment across GMFCS levels.

CONCLUSIONS

Data provide evidence for sustained efficacy and safety of multipattern incobotulinumtoxinA treatment in children and adolescents with upper-limb spasticity.

Immunogenicity of Botulinum Toxin Formulations: Potential Therapeutic Implications

Botulinum neurotoxins (BoNTs) are proteins produced by bacteria of the Clostridium family. Upon oral ingestion, BoNT causes the neuroparalytic syndrome botulism. There are seven serotypes of BoNT (serotypes A-G); BoNT-A and BoNT-B are the botulinum toxin serotypes utilized for therapeutic applications. Treatment with BoNT injections is used to manage chronic medical conditions across multiple indications. As with other biologic drugs, immunogenicity after long-term treatment with BoNT formulations may occur, and repeated use can elicit antibody formation leading to clinical nonresponsiveness. Thus, approaching BoNT treatment of chronic conditions with therapeutic formulations that minimize stimulating the host immune response while balancing patient responsiveness to therapy is ideal. Immunogenicity is a clinical limitation in many settings that use biologic drugs for treatment, and clinically relevant immunogenicity reduction has been achieved through engineering smaller protein constructs and reducing unnecessary formulation components. A similar approach has influenced the evolution of BoNT formulations. Three BoNT-A products and one BoNT-B product have been approved by the Food and Drug Administration (FDA) for therapeutic use: onabotulinumtoxinA, abobotulinumtoxinA, incobotulinumtoxinA, and rimabotulinumtoxinB; a fourth BoNT-A product, daxibotulinumtoxinA, is currently under regulatory review. Additionally, prabotulinumtoxinA is a BoNT-A product that has been approved for aesthetic indications but not therapeutic use. Here, we discuss the preclinical and clinical immunogenicity data that exist within the scientific literature and provide a perspective for considering immunogenicity as a key factor in choice of BoNT formulation.

Evaluating the Effect of Incobotulinumtoxin A for Glabellar, Forehead, and Crow's Feet Lines Using A High Dilution

BACKGROUND

As aesthetic preferences have evolved and patients wish their muscles to be relaxed, but not frozen, a higher dilution of incobotulinumtoxinA (INCO) has allowed for increased spread using fewer units, yet no studies to date have investigated the efficacy, longevity, and safety of hyperdiluted INCO.

OBJECTIVE

We evaluated the effect of incobotulinumtoxinA (INCO) in glabellar, forehead, and lateral periorbital lines using a high dilution.

METHODS

Subjects with moderate-to-severe upper facial lines at rest according to the Merz Aesthetics Scales™ (Merz Pharmaceuticals GmbH, Frankfurt am Main, Germany) received 15U of INCO to the glabellar (n=4 injection sites), 10U to the rest of the forehead (n=10 injection sites), and 5U to the lateral periorbital lines (n=3 injection sites/eye). Primary outcomes were physician- and subject-rated improvement at one month using the Global Aesthetic Improvement Scale (GAIS) and changes in line severity using the Merz Aesthetics Scales™.

RESULTS

The study included 15 women aged 35 to 65 years. At one month, physician GAIS scores indicated 91.2% of subjects were very much improved and 8.8% were much improved; 91.5%, 78.0%, and 57.6% of participants remained at least improved at four, five, and six months, respectively. Subject GAIS scores at one month were in agreement with physician scores. At one month, an improvement of at least one point in Merz Aesthetics Scales™ scores in glabellar, forehead, and lateral periorbital lines was reported in 88.9%, 98.3%, and 94.8% of participants, respectively. Subject satisfaction was high throughout the study. No treatment-related adverse events were observed.

CONCLUSION

Hyperdilute INCO was effective at improving overall appearance and reducing line severity in individuals with moderate-to-severe upper facial lines. Patient satisfaction was maintained up to six months and treatment was well tolerated.

Factors Influencing the Surgical Decision in Dystonia Patients Referred for Deep Brain Stimulation

There is no available data on the journey of dystonia patients once referred to a tertiary center to undergo deep brain stimulation (DBS). We hypothesized that some patients might be incorrectly diagnosed while others might decline the procedure or experience significant benefit with switching to a different botulinum neurotoxin (BoNT). This is a single-center, retrospective study of dystonia patients who were referred to the DBS program between January 2014 and December 2018. We collected data on the surgical decision as well as factors influencing this decision. Sixty-seven patients were included (30 males, mean age: 48.3 ± 20.1 years, disease duration: 16.9 ± 15.3 years). Thirty-three (49%) patients underwent DBS. Four (6%) patients were awaiting the procedure while the remaining 30 patients (45%) did not undergo DBS. Reasons for DBS decline were patient refusal (17, 53%), functional dystonia (6, 20%), and successful use of AbobotulinumtoxinA (3, 10%) in patients who had failed other BoNTs. Our study highlights the importance of structured patient education to increase acceptance of DBS, as well as careful patient evaluation, particularly with respect to functional dystonia. Finally, changing BoNT formulation might be beneficial in some patients.

IncobotulinumtoxinA for the Treatment of Blepharospasm in Toxin-Naïve Subjects: A Multi-Center, Double-Blind, Randomized, Placebo-Controlled Trial

This study aimed to assess the efficacy/safety of incobotulinumtoxinA (Xeomin^®, Merz Pharmaceuticals GmbH) in botulinum neurotoxin-naïve subjects with blepharospasm. Botulinum neurotoxin-naïve subjects (≥ 12 months without botulinum neurotoxin treatment for blepharospasm) received single-dose incobotulinumtoxinA 50 U, 25 U, or placebo. Subjects were followed for 6-20 weeks (main period). Qualified subjects entered an open-label extension period and received another incobotulinumtoxinA injection (≤ 70 U). The primary efficacy variable was change from baseline in the Jankovic Rating Scale (JRS) severity subscore at the main period of week 6. Other efficacy variables included changes in the Blepharospasm Disability Index score and JRS frequency subscore and sumscore. Adverse events were monitored. Sixty-one subjects were randomized (main period: incobotulinumtoxinA 50 U, n = 19; incobotulinumtoxinA 25 U, n = 22; placebo, n = 20); 39 entered the open-label extension period (9, 14, and 16 subjects from the incobotulinumtoxinA 50 U, incobotulinumtoxinA 25 U, and placebo groups [main period], respectively, changed to open-label extension period dosing). A statistically significantly greater reduction in JRS severity subscore was reported for subjects receiving incobotulinumtoxinA 50 U versus placebo (ANCOVA, least square mean difference: - 1.2, p = 0.0004). Subjects receiving incobotulinumtoxinA experienced improvements in other efficacy variables versus baseline and/or placebo. Sustained clinical improvements and low adverse event rates (22.2-42.1%) were observed. This is the second placebo-controlled, double-blind study that demonstrates favorable efficacy/safety of incobotulinumtoxinA in subjects with blepharospasm. IncobotulinumtoxinA is the first botulinum neurotoxin that could fulfill the American Academy of Neurology criteria for a Level A recommendation for blepharospasm.Trial registration ClinicalTrials.gov identifier, NCT01896895.

Intradermal injection of incobotulinumtoxinA for face lifting

Intradermal injection of botulinumtoxinA (BoNT/A) has been used off-label by many clinicians for the purpose of face-lifting effect. Some studies on AbobotulinumtoxinA (AboA) demonstrated clinical efficacy on face-lifting effect when comparing to normal saline solution (NSS). So far, there is no split-face comparison study on face-lifting effect of IncobotulinumtoxinA (IncoA). The objective of this study was to compare the face-lifting effect of IncoA intradermal injection and NSS. Twenty-two subjects were enrolled and randomly injected with IncoA at 1:6 cc dilution (100 unit or 1 vial in 6 cc of NSS) on one side, and NSS on the other side by using intradermal injection technique. Standardized photographic documentation with 2-, and 3-dimentional imaging system (Vectra H1, Canfield Scientific, Inc., Fairfield, NJ) were obtained at baseline, and at 2 weeks after treatment. The face-lifting effect was graded by the subjects and two blinded dermatologists, using photographic comparison. Side effects were also recorded at the end of the study. Immediate face-lifting was identified on the side that was treated with IncoA by blinded injectors in 63.6% of patients. Of all subjects, 17 (77.3%) have noticed the improvement of skin laxity on the side that was treated with IncoA at 2 weeks after treatment. The difference in facial contouring volume measured by Vectra H1 imaging system on IncoA side was significantly higher (P = .033) when comparing to NSS side in patients aged <36 years old. However, there was no statistically significant difference in face-lifting when comparing between IncoA and NSS evaluated by two blinded dermatologists (P = 1.00). Facial asymmetry was found in 36.4% of subjects. This study demonstrated the face-lifting effect of IncoA intradermal injection. Further studies with larger number of subjects and proper method of evaluation should be done to verify these findings.

Cost-Effectiveness of IncobotulinumtoxinA in the Treatment of Sialorrhea in Patients with Various Neurological Conditions

INTRODUCTION

Sialorrhea is a common and debilitating symptom associated with neurological conditions, which can result in considerable physical and psychosocial complications. In Australia, management options are limited and further impeded by the lack of approved treatments. Whilst there is emerging evidence for the efficacy and tolerability of botulinum toxin (BoNT) for the treatment of sialorrhea in patients with neurological conditions, the cost-effectiveness of the treatment is yet to be established.

OBJECTIVES

To evaluate the cost-effectiveness of incobotulinumtoxinA for the treatment of chronic troublesome sialorrhea caused by various neurological conditions from the Australian healthcare perspective.

METHODS

A Markov state transition model was developed to perform a cost-utility analysis comparing incobotulinumtoxinA with standard of care (SoC). The model consisted of a hypothetical cohort of patients transiting between three severity-based health states, defined according to the Drooling Severity and Frequency Scale (DSFS), in 16-weekly cycles over 5 years. All clinical and utility inputs were sourced from a single placebo-controlled randomised clinical trial. Only direct healthcare costs were considered, and potential indirect costs such as carer's time and lost productivity were ignored. The primary outcome measure was the incremental cost per quality-adjusted life-year (QALY). Univariate and probabilistic sensitivity analyses were conducted.

RESULTS

The model demonstrated that proportionally more patients spent time in less severe sialorrhea health states in the incobotulinumtoxinA arm. For example, over the 5-year period, patients receiving incobotulinumtoxinA were estimated to spend 1.6 years with minimal or no sialorrhea, while no patients achieved this level of improvement under SoC. IncobotulinumtoxinA was shown to have an incremental cost per QALY gained of A$23,445 when compared with SoC.

CONCLUSIONS

The quality of life (QoL) of patients with sialorrhea caused by neurological conditions was considerably compromised. IncobotulinumtoxinA was shown to successfully alleviate sialorrhea and it was demonstrated to be a cost-effective intervention when compared with SoC alone.

Treatment of Blepharospasm and Oromandibular Dystonia with Botulinum Toxins

Blepharospasm and oromandibular dystonia are focal dystonias characterized by involuntary and often patterned, repetitive muscle contractions. There is a long history of medical and surgical therapies, with the current first-line therapy, botulinum neurotoxin (BoNT), becoming standard of care in 1989. This comprehensive review utilized MEDLINE and PubMed and provides an overview of the history of these focal dystonias, BoNT, and the use of toxin to treat them. We present the levels of clinical evidence for each toxin for both, focal dystonias and offer guidance for muscle and site selection as well as dosing.

Efficacy of incobotulinumtoxinA for the treatment of adult lower-limb post-stroke spasticity, including pes equinovarus

BACKGROUND

Lower-limb spasticity can impair ambulation and gait, impacting quality of life.

OBJECTIVES

This ancillary analysis of the TOWER study (NCT01603459) assessed the efficacy of incobotulinumtoxinA for lower-limb post-stroke spasticity including pes equinovarus.

METHODS

Participants received escalating incobotulinumtoxinA doses (400-800U) across 3 injection cycles. Changes were compared for those treated in the lower limb (with/without upper-limb treatment) or the upper limb only or for participants treated or untreated for pes equinovarus. Outcome measures were those used in the seminal study: resistance to passive movement scale (REPAS), Ashworth Scale (AS), functional ambulation and lower-limb goal attainment.

RESULTS

Among 132/155 (85%) participants with post-stroke spasticity, in cycles 1, 2 and 3, 99, 119 and 121 participants received lower-limb treatment with mean (SD) total limb incobotulinumtoxinA doses of 189.2 (99.2), 257.1 (115.0) and 321.3 (129.2) U, respectively. Of these, 80, 105 and 107, respectively, were treated for pes equinovarus. The mean (SD) improvement in REPAS lower-limb score was greater with treatment in the lower limb versus the upper limb only: -1.6 (2.1) versus-0.4 (1.4); -1.9 (1.9) versus -0.6 (1.6); -2.2 (2.2) versus -1.0 (0.0) (P=0.0005, P=0.0133 and P=0.3581; analysis of covariance [ANCOVA], between-group differences) in cycles 1, 2 and 3, respectively. For all cycles, the mean improvement in ankle joint AS score from injection to 4 weeks post-treatment was greater for participants treated versus not treated for pes equinovarus, with a significant between-group difference in cycle 1 (P=0.0099; ANCOVA). At the end of cycle 3, 42% of participants walked independently and 63% achieved 2 of 2 lower-limb treatment goals (baseline 23% and 34%, respectively).

CONCLUSIONS

This study supports the efficacy of incobotulinumtoxinA for treatment of pes equinovarus and other patterns of lower-limb post-stroke spasticity.

Efficacy and safety of incobotulinumtoxinA in post-stroke upper-limb spasticity in Japanese subjects: results from a randomized, double-blind, placebo-controlled study (J-PURE)

Background

Upper-limb spasticity frequently occurs after stroke and there is a clinical need for more effective therapies. The Phase III J-PURE study assessed the efficacy and safety of incobotulinumtoxinA up to 400 U for post-stroke upper-limb spasticity in Japan.

Methods

In the 12-week main period (MP) of this double-blind, placebo-controlled study, Japanese subjects with upper-limb spasticity received one injection cycle of incobotulinumtoxinA 400 U, 250 U, or matching placebo. Eligible subjects enrolled in an open-label extension (OLEX) period of three injection cycles of incobotulinumtoxinA 400 U (32–40 weeks). The primary objective was to establish the efficacy of a single incobotulinumtoxinA injection using the Modified Ashworth Scale (MAS) wrist score. Secondary efficacy outcomes and safety were also assessed.

Results

Among 100 treated subjects, AUCs for incobotulinumtoxinA 400 and 250 U were significantly different versus placebo (p = 0.0014 and p = 0.0031, respectively) for change from baseline in MAS wrist score to the end of the MP, with similar results from baseline to week 4. IncobotulinumtoxinA 400 U was superior versus placebo across other spasticity patterns and at most study visits. Improvements were maintained throughout the OLEX period. Disability Assessment Scale and Investigator’s Clinical Global Impression scores improved significantly for incobotulinumtoxinA 400 U versus placebo from baseline to week 4 (p = 0.0067 and p < 0.0001, respectively). IncobotulinumtoxinA was well tolerated up to 52 weeks, with no unexpected adverse events.

Conclusion

IncobotulinumtoxinA reduced (pathologically) increased muscle tone, improved functionality and was well tolerated in Japanese subjects with post-stroke upper-limb spasticity.

Quality of life in subjects with upper- and lower-limb spasticity treated with incobotulinumtoxinA

Background

We evaluated quality of life among subjects with upper- and lower-limb spasticity who received escalating doses of incobotulinumtoxinA (total body doses up to 800 U) in the prospective, single-arm, dose-titration TOWER study.

Methods

In this exploratory trial, subjects (N = 155; 18–80 years of age) with upper- and lower-limb spasticity due to cerebral causes who were deemed to require total body doses of up to 800 U incobotulinumtoxinA received three consecutive injection cycles of incobotulinumtoxinA (400, 600, and up to 800 U), each with 12 to 16 weeks’ follow-up. QoL was assessed using the EuroQol 5-dimensions questionnaire, three-level (EQ-5D), before and 4 weeks post-injection in each injection cycle and at the end of injection cycle 3.

Results

The mean EQ-5D visual analog scale scores of 155 participants continuously improved from study baseline to 4 weeks post-injection in all injection cycles (mean [standard deviation] change 6.7 [14.1], 9.6 [16.3], and 8.6 [17.0] for injection cycles 1, 2, and 3, respectively; p < 0.0001 for all, paired sample t-test). In general, among those with a change in the EQ-5D rating of their condition, the proportion of subjects with ‘improvement’ was greater than that with ‘worsening’ for individual EQ-5D dimensions across all injection cycles. At the end of injection cycle 3, the proportion of subjects rating their condition as ‘normal’ increased from study baseline for all dimensions, and there was a ≥ 46% reduction in the proportion of subjects with a rating of ‘severe impairment’.

Conclusion

These preliminary results suggest that escalating incobotulinumtoxinA doses up to 800 U are associated with improvement in quality of life ratings in subjects with multifocal upper- and lower-limb spasticity, and form a basis for future comparator studies.

Trial registration

ClinicalTrials.gov, NCT01603459. Date of registration: May 22, 2012.

Novel Native and Engineered Botulinum Neurotoxins

Botulinum neurotoxins (BoNTs), produced by Clostridia and other bacteria, are the most potent toxins known. Their cleavage of the soluble N-ethylmaleimide-sensitive factor activating protein receptor (SNARE) proteins in neurons prevents the release of neurotransmitters, thus resulting in the muscle paralysis that is characteristic of botulism. This mechanism of action has been exploited for a variety of therapeutic and cosmetic applications of BoNTs. This chapter provides an overview of the native BoNTs, including the classical serotypes and their clinical use, mosaic BoNTs, and novel BoNTs that have been recently identified in clostridial and non-clostridial strains. In addition, the modular structure of native BoNTs, which are composed of a light chain and a heavy chain, is amenable to a multitude of novel fusions and mutations using molecular biology techniques. These novel recombinant BoNTs have been used or are being developed to further characterize the biology of toxins, to assist in vaccine production, to serve as delivery vehicles to neurons, and to be utilized as novel therapeutics for both neuronal and non-neuronal cells.

Long-term incobotulinumtoxinA treatment for chronic sialorrhea: Efficacy and safety over 64 weeks

BACKGROUND

Botulinum neurotoxin (BoNT) is an effective treatment for chronic sialorrhea; however, reliable and robust evidence supporting long-term efficacy and safety is lacking. This study investigated the efficacy and safety of repeated incobotulinumtoxinA injections for chronic sialorrhea over 64 weeks.

METHODS

Adults with sialorrhea were randomized (2:2:1) to incobotulinumtoxinA 75 U, incobotulinumtoxinA 100 U (n = 74 each), or placebo (n = 36) in the double-blind, placebo-controlled main period (NCT02091739). Eligible subjects entered the extension period and received dose-blinded incobotulinumtoxinA 75 or 100 U in three further 16±2-week injection cycles. Efficacy and safety assessments in subjects who received incobotulinumtoxinA throughout the study included unstimulated salivary flow rate (uSFR), subjects' Global Impression of Change Scale (GICS), Drooling Severity and Frequency Scale (DSFS), modified Radboud Oral Motor Inventory for Parkinson's Disease (mROMP) drooling, speech, and swallowing symptom scores, and incidence of adverse events (AEs).

RESULTS

In total, 173/184 subjects (94%) completed the main period and entered the extension period; 141 subjects received incobotulinumtoxinA 75 U (n = 69) or 100 U (n = 72) in both periods. Mean uSFR decreased consistently with repeated incobotulinumtoxinA 75 and 100 U treatment and by -0.16 and -0.17, respectively, at the end-of-study visit. Subjects' GICS, DSFS, and mROMP drooling scores also improved at all assessments. mROMP speech and swallowing scores remained stable. The most common treatment-related AEs during the extension period were dry mouth (4.4% and 11.1%) and dysphagia (1.5% and 4.2%).

CONCLUSIONS

Data support long-term efficacy and safety of repeated incobotulinumtoxinA treatment for sialorrhea, with no additional safety concerns reported over 64 weeks.

Comparing lanbotulinumtoxinA (Hengli®) with onabotulinumtoxinA (Botox®) and incobotulinumtoxinA (Xeomin®) in the mouse hemidiaphragm assay

LanbotulinumtoxinA (LAN) is manufactured and registered in China since 1994. Despite its widespread use in China and its increasing use in other Asian countries and in South America, it is not yet well known elsewhere. We wanted to compare its potency labelling using the mouse diaphragm assay (MDA), an isolated muscle model for botulinum toxin (BT) potency measurements, which is superior to clinical tests and which was recently refined as an alternative batch release assay for BT manufacturing. We also wanted to estimate LAN manufacturing quality by testing its inter-batch potency consistency. Potencies of 20, 60 and 100 MU of LAN, onabotulinumtoxinA (ONA) and incobotulinumtoxinA (INCO) were measured by the inversely related paresis time (PT) in the MDA. The PT (M ± SD) of all doses of LAN, ONA and INCO was 90.4 ± 27.0 min, 114.9 ± 46.5 min and 94.3 ± 29.9 min, respectively. Statistical analysis demonstrated indistinguishable potency labelling of LAN and INCO, but revealed a slightly lower potency of ONA compared to LAN and INCO. PT of LAN batch 1 and LAN batch 2 was 86.9 ± 21.2 min and 94.0 ± 32.8 min, respectively (no statistically significant difference), suggesting an adequate LAN manufacturing consistency. The MDA is an appropriate instrument for potency testing of BT drugs, including new ones currently under development. Our results allow comparing therapeutic effects, adverse effects and economics of LAN, ONA and INCO. They also suggest adequate manufacturing consistency of LAN.

IncobotulinumtoxinA for hypersalivation in patients with amyotrophic lateral sclerosis: an open-label single-centre study

The objective of this study is to discover whether incobotulinumtoxinA (inco) can reduce relative hypersalivation in patients with amyotrophic lateral sclerosis (ALS). 14 patients with ALS (8 males and 6 females, age 55.4 ± 16.3 years) received ultrasound-guided injection of inco 100 MU in both parotid glands and inco 50 MU in both submandibular glands. Saliva production was gravimetrically measured with three cotton rolls placed in the mouth. Weight increase after 5 min was measured on an electronic scale. Subjective saliva production was registered with drooling frequency scale (DFS) and drooling severity scale (DSS). Saliva production was gravimetrically reduced at week 4 (p = 0.04), week 8 (p = 0.01) but not after week 12 after BT application. DFS was reduced at week 4 (p = 0.04), week 8 (p = 0.02), but not after week 12. DSS was reduced at week 4 (p = 0.03), week 8 (p = 0.04) and week 12 (p = 0.04). Patients in our study did not experience changes in their swallowing patterns or any other safety-relevant events. Inco is effective and well tolerated for saliva reduction in patients with ALS for 8-12 weeks.

IncobotulinumtoxinA and Deep Brain Stimulation

Guidelines recommend Botulinum toxin-A (BoNT-A) after deep brain stimulation (DBS), although the effectiveness of their combined use is uncertain. A chart review of Parkinson's disease (17) and dystonia (7) patients undergoing 302 injections with IncobotulinumtoxinA before or after DBS was performed. Patients with cervical dystonia received less IncobotulinumtoxinA after DBS (290.7 ± 124.0 vs. 192.4 ± 131.4, p = 0.005) and experienced an increased benefit (4.0 ± 3.4 vs. 8.4 ± 3.6 weeks, p = 0.003). No significant differences were found when comparing the treatment outcomes of 14 patients who received both IncobotulinumtoxinA and OnabotulinumtoxinA after DBS. The use of BoNT-A after DBS is a useful strategy although prospective studies are needed.

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.

Antibody-induced failure of botulinum toxin therapy: re-start with low-antigenicity drugs offers a new treatment opportunity

Botulinum toxin (BT) can stimulate formation of BT antibodies (BTAB) thus producing Antibody-Induced Therapy Failure (ABTF). BTAB titres may drop eventually. When BT therapy is then re-started with conventional BT drugs, BTAB titres re-increase promptly. We wanted to study whether the use of the low-antigenicity BT drug incobotulinumtoxinA (INCO) can prevent this re-increase. 8 patients with cervical dystonia and ABTF with maximal BTAB titres (6 women, 2 men, age 41.4 ± 12.1 years, disease duration 6.6 ± 4.7 years) were studied. ABTF ocurred under onabotulinumtoxinA (ONA) in five patients and under abobotulinumtoxinA (ABO) in 3 after 8.8 ± 3.8 injection series and a treatment time of 962.0 ± 473.2 days. After 3881.5 ± 2468.3 days without BT, all BTAB titres had dropped to insignificant levels before BT therapy was re-started with INCO. Treatment parameters before and after re-start were as follows: single dose 219.2 ± 90.7 MU vs 252.6 ± 109.0 MU (ns), interinjection interval 119.7 ± 18.4 vs 104.5 ± 14.7 days (ns), cumulative dose 1893.8 ± 1161.6 MU vs 5130.4 ± 3602.5 MU (ns), treatment time 962.0 ± 505.9 vs 1895.4 ± 1211.4 days (ns) and number of injection series 8.8 ± 3.8 vs 19.3 ± 11.8 (ns). Repeated BTAB measurements and clinical examinations did not reveal any signs of ABTF after re-start. INCO offers a new and long-term treatment opportunity for ABTF patients when their BTAB titres have dropped. Our observations also confirm lower antigenicity of INCO compared to conventional BT drugs.

Comparing incobotulinumtoxinA (Xeomin®) and onabotulinumtoxinA (Botox®): identical potency labelling in the hemidiaphragm assay

Botulinum toxin (BT) is provided by several manufacturers producing a number of different drugs. Their potency is given in internationally standardised mouse units (MU). Clinical practise, however, reveals that the potency labelling of different BT drugs may not be identical. We wanted to use the mouse diaphragm assay (MDA) to compare the two BT drugs onabotulinumtoxinA (ONA) and incobotulinumtoxinA (INCO). For this, we measured the paresis time (PT) of different ONA or INCO doses. All BT came from several different and unexpired drug batches. PT for 20MU were 169.7 ± 28.9 min (ONA) and 132.3 ± 1.5 min (INCO) (p = 0.089), for 60MU 105.3 ± 10.1 min and 84.7 ± 4.2 min (p = 0.031), for 100MU 69.7 ± 1.5 min and 66.0 ± 7.0 min (p = 0.462) and for 140MU 74.7 ± 0.6 min and 62.3 ± 2.1 min (p = 0.100), respectively. The overall PT were 104.8 ± 12.5 and 86.3 ± 8.5 min (p = 0.178). Results presented here do not reveal differences in potency labelling between ONA and INCO, even when the full range of therapeutic doses are examined, although there was a trend towards stronger INCO effects. Data confirm previous reports on identical potency labelling of ONA and INCO. The MDA seems to be an appropriate instrument to test the potency labelling of other BT drugs as well, including new BT drugs currently under development.

Botulinum toxin in essential hand tremor - A randomized double-blind placebo-controlled study with customized injection approach

INTRODUCTION

To evaluate the safety and efficacy of incobotulinumtoxinA (IncoA) injection for treatment of essential hand tremor. In essential tremor and Parkinson's disease tremor, administration of onabotulinumtoxinA via a fixed injection approach improves the tremor but a high percentage of patients (30-70%) develop moderate to severe hand weakness which has limited its use in clinical practice.

METHODS

This study was performed from July 2013 to July 2016 on 33 subjects. This is a double-blind, placebo-controlled, crossover trial injecting 80-120 units of IncoA into 8-14 hand and forearm muscles using a customized approach. The subjects were followed for 28 weeks. The treatment efficacy was evaluated by the Fahn Tolosa Marin tremor rating score and NIH genetic criteria for tremor severity at 4 and 8 weeks after each of the two sets of treatments. Hand strength was assessed by an ergometer.

RESULTS

There was statistically significant improvement in clinical rating score of tremor at 4 and 8 weeks following the IncoA injection.

CONCLUSION

In this study, injection of IncoA treatment via a customized approach improved essential tremor on the clinical scales and patient's perception with a low occurrence of significant hand weakness.

Botulinum neurotoxin A injection for the treatment of epiphora with patent lacrymal ducts

HEADINGS

Retrospective longitudinal study to evaluate the efficacy of botulinum neurotoxin A (BoNT/A) therapy for epiphora with patent lacrimal ducts.

BACKGROUND/PURPOSE

BoNT/A has been used since 2000 in axillary hyperhidrosis to reduce sweat secretion. Some isolated cases of hyperlacrimation or crocodile tear syndrome have been treated with BoNT/A on this basis. We report our experience in the treatment of tearing despite patent lacrimal ducts by BoNT/A injection into the lacrimal gland.

METHODS

We reviewed qualitative and quantitative criteria to evaluate the degree of improvement of epiphora after BoNT/A injections in the palpebral lobe of the lacrimal gland in patients referred for epiphora despite patent lacrimal ducts between 2009 and 2016. Epiphora was graded using a functional questionnaire, Munk score and Schirmer test performed before and after the injections. Side effects were recorded.

RESULTS

Sixty-five palpebral lacrimal glands of forty-two patients with epiphora despite patent lacrimal ducts, of mean age 65 years, sex ratio 0.8, were treated with BoNT/A (IncobotulinumtoxinA, XEOMIN^®, MERZ Pharma France) from April 2009 to April 2016. The etiology of the epiphora was represented by 56 paroxysmal lacrimal hypersecretion, 2 crocodile tear syndrome and 7 facial palsies. No conventional medical or surgical treatment had been effective in these cases. The technique of injection, dilution and dosage of BoNT/A were specific. We re-injected 33/65 cases a second time upon patient request due to recurrence of epiphora, 16/65 cases three times, 8/65 cases four times, 6/65 cases five times and 3/65 six times. The Schirmer's test measured a decrease of lacrimal secretion in 51/65 glands (78%) after the first botulinum neurotoxin injection. Side effects were limited to ptosis in 2 cases (3%) and six patients (9%) with rapidly regressing diplopia. Two patients experienced immediate lacrimal gland hematoma (3%) with no sequelae. The authors describe the injection techniques, the dosage, the volume and concentration of BoNT/A.

CONCLUSION

Patients with intractable epiphora despite patent lacrimal ducts can be effectively treated with BoNT/A (IncobotulinumtoxinA) injection into the palpebral lobe of the lacrimal gland. Most of the patients (80%) were very satisfied with few side effects (hematoma, ptosis or mild diplopia lasting from 3 days to 3 weeks). More studies are needed to delineate which types of epiphora can be treated with BoNT A.

IncobotulinumtoxinA Injection for Temporomandibular Joint Disorder

OBJECTIVES

Temporomandibular disorder (TMD) involves dysfunction of the temporomandibular joint and associated muscles of mastication causing pain with chewing, limitation of jaw movement, and pain. While the exact pathophysiology of TMD is not completely understood, it is thought that hyperfunction of the muscles of mastication places stress on the temporomandibular joint, leading to degeneration of the joint and associated symptoms. We hypothesize that chemodenervation of the muscles of mastication with IncobotulinumtoxinA (Xeomin) will decrease the stress on the temporomandibular joint and improve pain associated with temporomandibular joint and muscle disorder (TMJD).

METHODS

Twenty patients were randomized to IncobotulinumtoxinA (170 units) or saline injection of the masticatory muscles. Patient-reported pain scale (0-10) was recorded at 4-week intervals following injection for 16 weeks. Patients who received saline injection initially were assessed for reduction in pain at the first 4-week interval and if still had significant pain were rolled over into the IncobotulinumtoxinA arm.

RESULTS

Preinjection pain scores were similar between patients. While there was a statistically significant reduction in pain score in the placebo group one month, there was an overall larger drop in average pain scores in those patients injected with IncobotulinumtoxinA initially. All patients initially injected with placebo crossed over into the IncobotulinumtoxinA group. Similar results were seen when examining the composite masticatory muscle tenderness scores. There was no significant change in usage of pain medication.

CONCLUSIONS

We demonstrate utility of IncobotulinumtoxinA in treating patients with TMD with pain despite pain medication usage and other conventional treatments.

Treatment of Plantar Fasciitis With Botulinum Toxin

BACKGROUND

This study examined the effect of botulinum toxin upon plantar fasciitis through a randomized, controlled, and blinded trial.

MATERIALS

Between 2012 and 2015, 50 patients presented with plantar fasciitis. Twenty-five patients each randomly received an IncobotulinumtoxinA (IBTA) or saline injection of their affected foot. Pre- and postinjection function and pain were graded with the Foot and Ankle Ability Measures (FAAM) and visual analog scale (VAS), respectively. All 50 study patients who randomly received either placebo or IBTA presented at 6 and 12 months after injection.

RESULTS

At 6 months, the mean FAAM increased from 35.9 to 40.9 of 100, and the mean pain score decreased from 8.4 to 7.9 of 10 within the placebo group. At 6 months, the mean FAAM increased from 36.3 to 73.8 of 100, and mean pain score decreased from 7.2 to 3.6 of 10 within the IBTA group. These postinjection scores were significantly better than the placebo group ( P = .01). At 12 months after injection, the IBTA group maintained significantly better function and pain than the placebo group ( P < .05). By that time, 0 (0%) and 3 (12%) patients who received IBTA and saline, respectively, underwent surgery for recalcitrant plantar fasciitis ( P < .005).

CONCLUSION

Compared with placebo saline injection, using IBTA to treat plantar fasciitis resulted in significantly better improvement in foot function and pain. IBTA also lessened the need for operative treatment of plantar fasciitis.

LEVEL OF EVIDENCE

I, Randomized, double-blinded, placebo-controlled study.

Quality of life and costs of spasticity treatment in German stroke patients

OBJECTIVE

To gather data about the medical and non-medical health service in patients suffering from post-stroke spasticity of the upper limb and evaluate treatment effectiveness and tolerability as well as costs over the treatment period of one year.

METHODS

Prospective, non-interventional, multicenter, parallel-group study comparing effectivenessand costs of incobotulinumtoxinA (INCO) treatment (n = 118) to conventional (CON) antispastic therapy (n = 110) for upper limb spasticity after stroke in 47 clinical practices across Germany over a 1-year treatment period. IncobotulinumtoxinA was applied according to the individual treatment algorithms of each participating site and additional antispastic treatments were allowed. Primary efficacy objective was the reduction of the muscle tone measured by Ashworth scale. Responder analyses and logistic regressions were performed. Quality of life, measured by SF-12 questionnaire and functional disability were assessed. Besides calculating treatment costs, a cost-utility analysis was performed.

RESULTS

Responder rates of all muscle groups of the upper extremities were significantly higher in the treatment group (62.9-86.2 % vs. 15.5-26.9 %, p < 0.01). Total health service costs were twice as high in the INCO group, however cost-utility ratios were consistently superior compared to the control group. Lowest incremental costs were documented to improve the "physical health" dimension in quality of life.

CONCLUSION

Higher responder rates, higher increases in quality of life and superior cost-utility ratios in the BoNT/A-treatment group underline guideline recommendations for botulinum toxin A treatment in focal or segmental spasticity. Results may partially be influenced by different patient demographics or disease severity at study entry.

In-vivo comparison of the neurotoxic potencies of incobotulinumtoxinA, onabotulinumtoxinA, and abobotulinumtoxinA

Three botulinum neurotoxin type A (BoNT/A) products, incobotulinumtoxinA, onabotulinumtoxinA, and abobotulinumtoxinA, all manufactured by different methods, are employed in clinical practice. Comparing the three BoNT/A products is difficult because their concentrations and volumes differ and the precise dose equivalence ratio is not known. We aimed to compare the neurotoxic potencies by a systematic analysis of injected volume and dose. The potency of BoNT in inducing hind limb paresis was assessed by analyzing the wheel-running performance of mice. To standardize the volume, the effect of an identical dose of incobotulinumtoxinA dissolved in different volumes of saline (15, 10, 5, and 2μl) was studied in four groups of mice (n=13-15). The potencies of the BoNT products were then compared by injecting identical volumes (10μl) containing different doses into both hind leg muscles. Mice injected with incobotulinumtoxinA showed a volume-dependent reduction in wheel-running, with larger volumes inducing more intense paresis. A standardized volume containing the same number of mouse units of the BoNT/A products produced different degrees of paresis. The conversion ratio of incobotulinumtoxinA and onabotulinumtoxinA is estimated to be between 1:0.75 and 1:0.5. OnabotulinumtoxinA displayed a two-fold greater potency than abobotulinumtoxinA. Doses of onabotulinumtoxinA and abobotulinumtoxinA that produce an identical severity of pareses even result in the same duration of pareses. This wheel-running assay allows one to compare the neurotoxic potency of different volumes and doses of the BoNT products in vivo. Our results argue against common clinical practice because incobotulinumtoxinA and onabotulinumtoxinA are not readily interchangeable and a two-fold dose of abobotulinumtoxinA is needed to induce an effect identical to onabotulinumtoxinA. In addition, this emphasizes that the duration of BoNT-induced effect is the same as long as equipotent doses of BoNT are injected.

The role of neurotoxins in the periorbital and midfacial areas

Initially popularized for the treatment of strabismus and blepharospasm, injection of botulinum neurotoxin has become the most commonly performed cosmetic treatment in the United States. Injection techniques have been particularly well-studied in the midface and periocular region, and patient satisfaction tends to be very high. We review the salient differences among available neurotoxins, how to optimally reconstitute them, how to inject the forehead, glabella, lateral canthal lines ("crow's feet"), infralid region, and transverse nasal lines ("bunny lines"), how to sculpt the brow, and how to manage potential complications.

Satisfaction with botulinum toxin treatment in post-stroke spasticity: results from two cross-sectional surveys (patients and physicians)

OBJECTIVE

To characterize patient and physician satisfaction with current standard-of-care botulinum toxin treatment regimens for symptom control in patients with post-stroke spasticity using structured interviews with patients and physicians.

RESEARCH DESIGN AND METHODS

Two cross-sectional surveys were conducted in Canada, France, Germany, and the US. The patient survey included patients with post-stroke spasticity who had undergone at least two botulinum toxin A injection cycles. Information on patients' current and prior botulinum toxin treatment cycles and quality of life was collected. The physician survey included physicians treating post-stroke spasticity with botulinum toxins and collected information regarding physician satisfaction with botulinum toxin treatment for post-stroke spasticity.

RESULTS

Of 79 participating patients with post-stroke spasticity, 61 (77%) received treatment with onabotulinumtoxinA, 15 (19%) with abobotulinumtoxinA, and three (4%) with incobotulinumtoxinA. Overall, 40.5% of patients were very satisfied, 48.1% were somewhat satisfied, and 11.4% were not at all satisfied with botulinum toxin treatment. Patient satisfaction was lowest just before injection and highest at the time of peak effect. The mean injection interval was 13.7 (SD = 3.5) weeks; however, 43.4% of patients expressed a preference for intervals of ≤ 10 weeks. Most of the 105 participating physicians' were moderately (57.7%) or very (36.5%) satisfied with botulinum toxin treatment. However, physicians estimated that 16.2% of their patients with post-stroke spasticity could benefit from shorter injection intervals, and that 24.6% of patients could benefit from higher doses than those permitted by current country directives.

STUDY LIMITATIONS

Patients' responses were based on subjective recollections and physicians' responses were based on general impressions.

CONCLUSIONS

These surveys indicate that patients' and physicians' satisfaction with botulinum toxin therapy for post-stroke spasticity is overall very good. However, patients' satisfaction over the treatment cycle varied with onset, peak, and trough of treatment effects and patients and physicians expressed a need for treatment individualization.