Conversion ratio between Dysport and Botox in clinical practice: an overview of available evidence

Exploring botulinum toxin's impact on masseter hypertrophy: a randomized, triple-blinded clinical trial

The present study aimed to assess the effectiveness and functional adverse effects of a single and multiple injections of botulinum toxin A (BoNT-A) for masseter hypertrophy (MH). Twenty-six women complaining about lower third facial enlargement due to MH, received 75 U of BoNT-A (abobotulinum toxin) in each masseter muscles. After 3 months, patients were randomly assigned to receive a second treatment session of Saline Solution: (G1; n = 11) or BoNT-A: (G2; n = 12). Muscle thickness (ultrasound), electrical activity (electromyography; EMG), masticatory performance, and subjective perception of MH were evaluated. Follow-up was performed at 1, 3 and 6 months. Muscle thickness, EMG activity, and masticatory performance were analyzed using ANOVA two-way and Sidak test as post-hoc. Masticatory performance was analyzed by the Friedman's test and Mann-Whitney test. Regarding inter-groups comparisons, there was a significant decrease in the left masseter muscle thickness in the G2 group at the 6 month follow-up (p < 0.02). For EMG, significant differences were evident at the 6 month assessment, with higher masseter activity for G1 (p < 0.05). For masticatory performance, no significant differences were observed throughout the study (p > 0.05) and a higher improvement in subjective perception of MH was observed in the 1 month follow-up for G2 (p < 0.05). In conclusion, BoNT-A is effective for MH, however multiple injections cause functional adverse effects in masseter muscle.

A novel technique of botulinum toxin injection around skull sutures for chronic migraine: A randomized controlled clinical trial

Background

Migraine is a chronic headache manifested with attacks. Here we aimed to evaluate and compare the efficacy of 15-point Dysport injection with 31-point Xeomin injections.

Materials and Methods

This is a randomized clinical trial performed in 2020-2021 in Isfahan on patients with refractory chronic migraine. A total number of 60 patients entered the study. The pain of patients was also determined using headache impact test (HIT) questionnaire. Patients were randomized into two groups: Group 1 underwent 31-point Xeomin injection and Group 2 underwent 1 vial of Dysport injection into 15 points of the scalp.

Results

Our study revealed that the data regarding aura, nausea, vomit, photosensitivity, sensitivity to sounds and smells did not change significantly between two groups compared to the beginning of the study. Frequency, duration, intensity of headaches, and the mean HIT score of all patients improved significantly within 3 months after interventions. Comparing both groups showed no significant differences (P > 0.05). HIT score was decreased from 21.26 ± 3.58 before intervention to 15.51 ± 4.58 after 3 months in Group 1 and 22.23 ± 2.59-10.33 ± 2.26 in Group 2. In both groups, these changes were statistically significant (P < 0.001). Although we found more decrease of HIT score in Group 2 comparing with Group 1 (10.33 ± 2.26 vs. 15.51 ± 4.58), this difference was not statistically significant (P = 0.12).

Conclusion

Although Xeomin and Dysport injections are both effective and reduced pain in patients with chronic migraine, our new technique is probably better than the standard technique. Because the injection points are halved, increase patients comfort and reduce overall cost.

Descriptive analysis of the annual cost of treating spasticity with different types of botulinum toxin A

INTRODUCTION

Botulinum toxin A is the first-line treatment for localised spasticity. However, the economic impact of this treatment is not fully known. This study aimed to describe the real costs of botulinum toxin A for the treatment of adult patients with spasticity at a spasticity clinic pertaining to a rehabilitation service, over a period of one year.

METHODS

We retrospectively reviewed all medical procedures carried out during the year 2017. We collected data on the type of toxin used (incobotulinumtoxin A, onabotulinumtoxin A, or AAbobotulinumtoxin A), the number of units injected, the anatomical region, and the time elapsed between infiltrations. The costs of medication and indirect costs, such as staff and consumables, were also calculated.

RESULTS

This is the first study to describe the real costs of botulinum toxin treatment of spasticity in adult patients in Spain. In 2017, 510 infiltration procedures were performed in 164 patients. The total cost of treating spasticity in our service was €116 789.70. The mean annual cost per patient was €603.64 for onabotulinumtoxin A, €642.69 for abobotulinumtoxin A, and €707.59 for incobotulinumtoxin A.

CONCLUSIONS

Our economic study of real clinical practice is consistent with the theoretical models published in the literature. The different characteristics of each toxin and the inability to establish an equivalence between the units of each drug prevents us from directly comparing these costs.

Immunogenicity of botulinum toxin

Botulinum toxin treatment is the most common non-surgical cosmetic treatment. Although there are many available treatments using botulinum toxin, their effects are temporary and repeated injections are required. These frequent injections can trigger an immunological response. In addition, botulinum toxin acts as an antigen in the body; thus, its effect disappears progressively due to this immunological reaction, which may cause treatment failure. Active botulinum toxin consists of a core neurotoxin and complexing proteins, the exact effects of which remain unclear. However, the complexing proteins are closely related to the immune response and the formation of neutralizing antibodies. Since neutralizing antibodies can lead to treatment failure, their formation should be prevented. Furthermore, various methods of detecting neutralizing antibodies have been used to predict treatment failure.

Descriptive analysis of the annual cost of treating spasticity with different types of botulinum toxin A

INTRODUCTION

Botulinum toxin A is the first-line treatment for localised spasticity. However, the economic impact of this treatment is not fully known. This study aimed to describe the real costs of botulinum toxin A for the treatment of adult patients with spasticity at a spasticity clinic pertaining to a rehabilitation service, over a period of one year.

METHODS

We retrospectively reviewed all medical procedures carried out during the year 2017. We collected data on the type of toxin used (incobotulinumtoxin A, onabotulinumtoxin A, or Abobotulinumtoxin A), the number of units injected, the anatomical region, and the time elapsed between infiltrations. The costs of medication and indirect costs, such as staff and consumables, were also calculated.

RESULTS

This is the first study to describe the real costs of botulinum toxin treatment of spasticity in adult patients in Spain. In 2017, 510 infiltration procedures were performed in 164 patients. The total cost of treating spasticity in our service was €116 789.70. The mean annual cost per patient was €603.64 for onabotulinumtoxin A, €642.69 for abobotulinumtoxin A, and €707.59 for incobotulinumtoxin A.

CONCLUSIONS

Our economic study of real clinical practice is consistent with the theoretical models published in the literature. The different characteristics of each toxin and the inability to establish an equivalence between the units of each drug prevents us from directly comparing these costs.

Effects of Natural Products on Neuromuscular Junction

Neuromuscular junction (NMJ) disorders result from damage, malfunction or absence of one or more key proteins involved in neuromuscular transmission, comprising a wide range of disorders. The most common pathology is antibody-mediated or downregulation of ion channels or receptors, resulting in Lambert-Eaton myasthenic syndrome, myasthenia gravis, and acquired neuromyotonia (Isaac's syndrome), and rarely congenital myasthenic syndromes caused by mutations in NMJ proteins. A wide range of symptomatic treatments, immunomodulating therapies, or immunosuppressive drugs have been used to treat NMJ diseases. Future research must be directed at better understanding of the pathogenesis of these diseases, and developing novel disease-specific treatments. Numerous secondary metabolites, especially alkaloids isolated from plants have been used to treat NMJ diseases in traditional and clinical practices. An ethnopharmacological approach has provided leads for identifying new treatment for NMJ diseases. In this review, we performed a literature survey in Pubmed, Science Direct, and Google Scholar to gather information on drug discovery from plant sources for NMJ disease treatments. To date, most research has focused on the effect of herbal remedies on cholinesterase inhibitory and antioxidant activities. This review provides leads for identifying potential new drugs from plant sources for the treatment of NMJ diseases.

[Therapeutic strategies for oromandibular dystonia]

Oromandibular dystonia is characterized by tonic or clonic involuntary spasms of the masticatory, lingual and / or muscles in the stomatognathic system. It is often misdiagnosed as craniomandibular dysfunction or psychiatric disease. According to clinical features, the oromandibular dystonia is classified into 6 subtypes (jaw closing-, jaw opening-, tongue-, jaw deviation-, jaw protrusion-, and lip dystonia). There are several treatment methods like botulinum toxin injection, muscle afferent block (injection of lidocaine and alcohol into the masticatory or tongue muscles for blocking muscle afferents from muscle spindle), occlusal splint, and oral surgery (coronoidotomy). Most of patients can be treated successfully according to subtype by combination of these treatments. Special treatment recommendations for each subtype were described in this focus article. Accurate diagnosis and treatment of oral dystonia requires comprehensive knowledge and skills of both oral and maxillofacial surgery and neurology. Therefore, collaboration among these departments is very important.

Clinical Improvement After Treatment With IncobotulinumtoxinA (XEOMIN®) in Patients With Cervical Dystonia Resistant to Botulinum Toxin Preparations Containing Complexing Proteins

This study investigated the clinical long-term effect of incobotulinumtoxinA (incoBoNT/A) in 33 cervical dystonia (CD) patients who had developed partial secondary therapy failure (PSTF) under previous long-term botulinum toxin (BoNT) treatment. Patients were treated four times every 12 weeks with incoBoNT/A injections. Physicians assessed treatment efficacy using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) at the baseline visit, week 12 and 48. Patients rated quality of life of CD with the Craniocervical Dystonia Questionnaire (CDQ-24). Titres of neutralizing antibodies(NAB) were determined at start of the study and after 48 weeks. All patients had experienced significant and progressive worsening of symptoms in the last 6 months of previous BoNT treatment. Repeated incoBoNT/A injections resulted in a significant reduction in mean TWSTRS at week 12 and 48. Patients' rating of quality of life was highly correlated with TWSTRS but did not change significantly over 48 weeks. During the 48 weeks -period of incoBoNT/A treatment NAB titres decreased in 32.2%, did not change in 45.2%, and only increased in 22.6% of the patients. Thus, repeated treatment with the low dose of 200 MU incoBoNT/A over 48 weeks provided a beneficial clinical long-term effect in PSTF and did not booster titres of NAB.

Botulinum Toxin Injections for Leg Contouring in East Asians

BACKGROUND

A common aesthetic concern among East Asian women is enlarged calves. Although surgical resection has been a traditional treatment option, botulinum toxin injections into the gastrocnemius muscle are an emerging, noninvasive alternative.

OBJECTIVE

To perform a literature review on botulinum toxin injections for leg contouring.

MATERIALS AND METHODS

A literature review was conducted using PubMed, Web of Science, Embase, and Cochrane's CENTRAL database to identify articles relating to combinations of the terms botulinum toxin, gastrocnemius, calves, and leg contouring.

RESULTS

Based on the limited publications to date, the authors prepared a review on how to treat an enlarged calf with botulinum toxin including injection techniques, anticipated efficacy, outcome monitoring, and potential side effects.

CONCLUSION

Botulinum toxin injections for calf reduction are an emerging, noninvasive treatment option. Studies to date suggest that it is an efficacious method with few immediate side effects. Future areas for investigation include defining the criteria for calf hypertrophy, minimum effective dosage of botulinum toxin, and the potential long-term effects of injections.

Botulinum Toxin for the Treatment of Intractable Raynaud Phenomenon

Raynaud phenomenon (RP) is a condition causing vasospasm in the fingers and toes of patients that can have a significant negative impact on quality of life. This can lead to pain, ulceration, and possible loss of digits. Several pharmacological options are available for treatment. However, RP can often be refractory to traditional modalities, leaving surgery or injections as the next available options. This article provides a review and update on the use of botulinum toxin as an effective therapy for the treatment of RP refractory to medical management.

Real-life outcomes in spasticity management: features affecting goal achievement

BACKGROUND/OBJECTIVE

Spasticity is a complex and common condition but there is a lack of 'real-world' data on goal setting and spasticity treatment, as well as identifying those features that might be associated with goal achievement. Our aim was to provide such data.

METHODS

Prospective attenders at a multi-disciplinary spasticity clinic over 2 years followed for consecutive appointments. Patient demographics and doses of botulinum toxin injected were documented. Main outcome was achievement of a primary goal but secondary goals were also recorded. Independent variables were examined for association to the outcome.

RESULTS

A total of 606 goals were set in 224 patients. The majority (75.2%) were achieved with similar levels across active (72.5%), passive (75.7%) and pain (78.6%) goals. However, in terms of the primary goal, active primary goals were achieved less frequently (59.7%) than non-active primary goal (74.2%). A logistic regression confirmed that this was the only independent variable associated with primary goal achievement. The majority of patients (61.6%) required changes to their treatment between appointments, irrespective of time since diagnosis, age or aetiology.

CONCLUSIONS

Most goals set in spasticity clinic can be achieved irrespective of type of goal. However, active goals may be harder to accomplish when they are set as a primary goal. This may reflect the desire of individuals to prioritise a desirable goal rather than one that is achievable. While goal setting is important in the management of spasticity patients, very few patient or treatment factors are associated with outcome prediction. Further work needs to identify features that may predict successful outcome.

Inequalities in pharmacologic treatment of spasticity in Sweden - health economic consequences of closing the treatment gap

BACKGROUND

The Swedish Healthcare Act states that patients should have equal access to healthcare. This study addresses at how this translates to pharmacological treatment of adult spasticity, including injections with botulinum toxin A (BoNT-A) and pumps for intrathecal baclofen (ITB). To address potential economic incentives for treatment differences, the results are also set into a health economic perspective. Thus, the current study provides a detailed and comprehensive overview for informed decision- and policymaking.

METHODS

Botulinum toxin use was retrieved from sales data. Clinical practice regarding mean BoNT-A treatment dose and proportion used for spasticity indication were validated in five county councils, while the number of ITB pumps were mapped for all county councils. Published costs and quality of life data was used for estimating required responder rates for cost-balance or cost-effectiveness.

RESULTS

The proportion of patients treated with BoNT-A varied between 5.8% and 13.6% across healthcare regions, with a mean of 9.2% on a national level. The reported number of ITB pumps per 100,000 inhabitants varied between 3.6 and 14.1 across healthcare regions, with a national mean of 6/100,000. The estimated incremental cost for reaching treatment equity was EUR 1,976,773 per year for BoNT-A and EUR 3,326,692 for ITB pumps. Based on expected cost-savings, responder rates ranging between 4% and 15% cancelled out the incremental cost for BoNT-A. Assuming no cost-savings, responder rates of 14% or 36% was required for cost-effectiveness.

CONCLUSIONS

There is a marked variation in pharmacologic treatment of adult spasticity in Sweden. Overall, the results indicate an underuse of treatment and need for harmonisation of clinical practice. Furthermore, the incremental cost for reaching treatment equity is likely to be offset by spasticity-associated cost-savings.

Effect of 3 Commercially Available Botulinum Toxin Neuromodulators on Facial Synkinesis: A Randomized Clinical Trial

Importance

Botulinum toxin neuromodulators are an important treatment for facial synkinesis. Whether a difference in efficacy exists among the 3 different botulinum neuromodulators used in treating this condition remains unknown.

Objective

To evaluate the effectiveness of 3 commercially available botulinum toxin neuromodulators in the treatment of facial synkinesis.

Design, Setting, and Participants

In this single-blind, 3-arm comparison randomized clinical trial, 28 patients at the Facial Nerve Center, University of Utah, Salt Lake City, were randomized to onabotulinumtoxinA, abobotulinumtoxinA, or incobotulinumtoxinA treatment. Each patient was given the Synkinesis Assessment Questionnaire (SAQ) to assess severity of synkinesis before treatment and 1, 2, and 4 weeks after treatment, and improvements were compared among the groups. Data were collected from July 3, 2012, to March 31, 2015.

Interventions

Botulinum toxin type A neuromodulator (onabotulinumtoxinA, abobotulinumtoxinA, or incobotulinumtoxinA) injected into synkinetic areas of the face.

Main Outcomes and Measures

Synkinesis assessed using the SAQ (score range, 20-100; lower scores indicate less severe synkinesis) before treatment and 1, 2, and 4 weeks after treatment.

Results

A total of 28 patients (mean [SD] age, 49.1 [18.5] years; 8 [28.6%] male and 20 [71.4%] female), with 6 patients enrolled multiple times, received 38 treatments (15 onabotulinumtoxinA, 13 abobotulinumtoxinA, and 10 incobotulinumtoxinA). No significant difference existed in baseline pretreatment SAQ scores among the 3 groups. Mean (SD) SAQ score improvement at 4 weeks was 41% (31%) for the onabotulinumtoxinA, 42% (20%) for the abobotulinumtoxinA, and 17% (18%) for the incobotulinumtoxinA groups. No significant differences were noted in SAQ score improvements among the 3 groups at weeks 1 and 2 after treatment (week 1 mean improvements of 42% in the onabotulinumtoxinA, 45% in the abobotulinumtoxinA, and 26% in the incobotulinumtoxinA groups; P = .19; week 2 mean improvements of 43% in the onabotulinumtoxinA, 46% in the abobotulinumtoxinA, and 28% in the incobotulinumtoxinA groups; P = .20). The difference in mean SAQ score improvement for abobotulinumtoxinA vs incobotulinumtoxinA from pretreatment to 4 weeks after treatment was not significant (30 vs 12 points; P = .11) despite a significant difference in mean total SAQ score for abobotulinumtoxinA vs incobotulinumtoxinA (40.34 vs 58.00; P = .02).

Conclusions and Relevance

AbobotulinumtoxinA had similar efficacy to onabotulinumtoxinA and incobotulinumtoxinA for the management of facial synkinesis up to 4 weeks after treatment. IncobotulinumtoxinA had significantly less effect on SAQ score improvement than onabotulinumtoxinA at 4 weeks, perhaps because of the shorter duration of action. Shorter intervals between treatments or larger doses may be required when using incobotulinumtoxinA treatment for facial synkinesis.

Trial Registration

clinicaltrials.gov Identifier: NCT03048383.

Level of Evidence

1.

A Functional Approach to Posttraumatic Salivary Fistula Treatment: The Use of Botulinum Toxin

This manuscript highlights key aspects regarding the practical use of botulinum toxin for the conservative nonsurgical treatment of a rarely encountered, but significant posttraumatic complication-the parotid salivary fistula. It adds information to the scarce existing literature on the subject. The authors outline the main differences between postoperative and trauma-related parotid injury regarding salivary fistula treatment. A total of 6 patients with trauma-related salivary fistulas have been treated by Abobotulinum toxin A injections over the course of 5 years. The technique is detailed, describing the doses used in the presence of parenchyma and duct injuries, the location and number of injection points in relation to the wound pattern. The results were favorable, leading to the healing of the salivary fistulas in all patients, with 1 injection session, without additional conservative treatment. In our experience, the use of botulinum toxin is of great benefit for treating salivary fistulas in a traumatic context.

[Conversion ratio between different botulinum neuroprotein product in neurological practice]

Despite nearly 30 years of experience in the application of botulinum toxin type A (BTA) in clinical practice, many fundamental questions of therapy remain valid. There are 5 botulinum toxin type A used for neurological indications in the Russian Federation in 2017. They contain different number of active neuroprotein (150 kDa) in a therapeutic dose of the drug that may have a potential impact on the efficacy and duration of action. The current SmPC of each BTA stated that the unit of activity is unique and can not be compared with any other BTA. In scientific publications one can find many details concerning the equivalence doses of onabotulinumtoxin A (botox) and abobotulinumtoxin A (dysport) and the ratio of units varies from 1:1 to 1:11. However, according to clinical guidelines, systematic reviews and high quality research evidence of recent years, the ratio of units of abobotulinumtoxin A (dysport) and onabotulinumtoxin A (botox) is 3(2,5):1. Use of a fixed ratio of units is possible only when switching from one drug to another or in case of limiting access to specific drug. Botulinum toxin type A is the first line of therapy in the treatment of several neurological diseases. The most commonly used drugs of botulinum toxin type A (botox, dysport, xeomin) have a significant evidence base that confirms their efficacy and optimal safety profile. The main difference between botulinum toxin type A is their potential activity of action, i.e., activity units and total therapeutic dose.

Botulinum Toxin for Neck Rejuvenation: Assessing Efficacy and Redefining Patient Selection

BACKGROUND

The "Nefertiti lift" consists of injecting the platysmal bands and the inferior border of the mandible with botulinum toxin. No clinical trial has evaluated its effect on the different lower face and neck aging components, and little is known about the clinical characteristics that predict treatment success.

METHODS

Patients were injected with abobotulinumtoxinA along the inferior border of the mandible and into the platysmal bands. Using standardized preinjection and postinjection photographs, the jowls, marionette lines, oral commissures, neck volume, and platysmal bands at maximal contraction and at rest were assessed with validated photonumeric scales. In addition, the overall appearance of the lower face and neck was evaluated by the Investigators and Subjects Global Aesthetic Improvement Score. Pain and patient satisfaction rates were also evaluated.

RESULTS

Thirty patients were injected with a mean dose of 124.9 U of abobotulinumtoxinA per patient. Platysmal bands at rest and with maximal tension reached a statistically significant improvement. The other components showed a tendency for improvement but did not reach statistical significance; 93.3 percent of investigators and patients rated the overall results as improved, and 96.6 percent of patients were satisfied with their results. When comparing the patients who improved the most to all the other patients, they had lower preinjection region-specific scores.

CONCLUSIONS

The Nefertiti lift can be used on its own or in conjunction with other rejuvenating procedures. It is particularly helpful in younger patients with platysma muscle hyperactivity and retained skin elasticity.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Comparative effectiveness of botulinum toxin versus non-surgical treatments for treating lateral epicondylitis: a systematic review and meta-analysis

Objectives:

To explore the effectiveness of botulinum toxin compared with non-surgical treatments in patients with lateral epicondylitis.

Methods:

Data sources including PubMed, Scopus, Embase and Airity Library from the earliest record to February 2017 were searched. Study design, patients’ characteristics, dosage/brand of botulinum toxin, injection techniques, and measurements of pain and hand grip strength were retrieved. The standardized mean differences (SMDs) in pain relief and grip strength reduction were calculated at the following time points: 2-4, 8-12, and 16 weeks or more after injection.

Results:

Six randomized controlled trials (321 participants) comparing botulinum toxin with placebo or corticosteroid injections were included. Compared with placebo, botulinum toxin injection significantly reduced pain at all three time points (SMD, -0.729, 95% confidence interval [CI], -1.286 to -0.171; SMD, -0.446, 95% CI, -0.740 to -0.152; SMD, -0.543, 95% CI, -0.978 to -0.107, respectively). Botulinum toxin was less effective than corticosteroid at 2-4 weeks (SMD, 1.153; 95% CI, 0.568-1.737) and both treatments appeared similar in efficacy after 8 weeks. Different injection sites and dosage/brand did not affect effectiveness. Botulinum toxin decreased grip strength 2-4 weeks after injection, and high equivalent dose could extend its paralytic effects to 8-12 weeks.

Conclusions:

When treating lateral epicondylitis, botulinum toxin was superior to placebo and could last for 16 weeks. Corticosteroid and botulinum toxin injections were largely equivalent, except the corticosteroid injections were better at pain relief in the early stages and were associated with less weakness in grip in the first 12 weeks.

Regional disparities in botulinum toxin A (BoNT-A) therapy for spasticity in Sweden: budgetary consequences of closing the estimated treatment gap

OBJECTIVES

As no national treatment guidelines for spasticity have been issued in Sweden, different regional treatment practices may potentially occur. This study examines botulinum toxin A (BoNT-A) treatment for spasticity on a regional level in Sweden and presents budgetary consequences of closing the estimated treatment gap.

MATERIALS AND METHODS

Prevalence of spasticity in Sweden was estimated from published data. Regional sales data for BoNT-A were acquired from IMS Health. A set proportion of hospital BoNT-A use was assumed to represent treatment of spasticity. Total intervention cost of BoNT-A treatment was gathered from healthcare regional tariffs, while costs associated with spasticity were derived from publications on multiple sclerosis and stroke.

RESULTS

Results show that the regional variation in treatment of spasticity with BoNT-A is large, with approximately every fourth patient being treated in Southern healthcare region compared to every tenth in the Stockholm-Gotland or Western healthcare regions. The incremental cost of filling the reported treatment gap was also assessed and was estimated at around 9.4 million EUR. However, for the incremental cost to be offset by savings in spasticity-related costs, only a small proportion of treatment responders (defined as patients transitioning to a lower severity grade of spasticity) was required (12%).

CONCLUSIONS

The study revealed apparent regional disparities of BoNT-A treatment for spasticity in Sweden. The results further suggest that the incremental cost of eliminating the treatment gap has a high probability of being offset by savings in direct costs, even at a low proportion of the patients reaching clinical improvement.

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.

Pharmaceutical, biological, and clinical properties of botulinum neurotoxin type A products

Botulinum neurotoxin injections are a valuable treatment modality for many therapeutic indications and have revolutionized the field of aesthetic medicine so that they are the leading cosmetic procedure performed worldwide. Studies show that onabotulinumtoxinA, abobotulinumtoxinA, and incobotulinumtoxinA are comparable in terms of clinical efficacy. Differences between the products relate to the botulinum neurotoxin complexes, specific biological potency, and their immunogenicity. Protein complex size and molecular weight have no effect on biological activity, stability, distribution, or side effect profile. Complexing proteins and inactive toxin (toxoid) content increase the risk of neutralizing antibody formation, which can cause secondary treatment failure, particularly in chronic disorders that require frequent injections and long-term treatment. These attributes could lead to differences in therapeutic outcomes, and, given the widespread aesthetic use of these three neurotoxin products, physicians should be aware of how they differ to ensure their safe and effective use.

Pharmacotherapy for the management of achalasia: Current status, challenges and future directions

This article reviews currently available pharmacological options available for the treatment of achalasia, with a special focus on the role of botulinum toxin (BT) injection due to its superior therapeutic effect and side effect profile. The discussion on BT includes the role of different BT serotypes, better pharmacological formulations, improved BT injection techniques, the use of sprouting inhibitors, designer recombinant BT formulations and alternative substances used in endoscopic injections. The large body of ongoing research into achalasia and BT may provide a stronger role for BT injection as a form of minimally invasive, cost effective and efficacious form of therapy for patients with achalasia. The article also explores current issues and future research avenues that may prove beneficial in improving the efficacy of pharmacological treatment approaches in patients with achalasia.

Neuronox versus BOTOX in the Treatment of Post-Stroke Upper Limb Spasticity: A Multicenter Randomized Controlled Trial

BACKGROUND

Botulinum toxin type A is widely used for treating spasticity. Neuronox (Neu-BoNT/A), a newly manufactured botulinum toxin a, has not yet been investigated for its efficacy and safety in the treatment of post-stroke upper limb spasticity.

OBJECTIVE

We evaluated the efficacy and safety of Neuronox (Neu-BoNT/A) compared with BOTOX (onabotulinum toxin A) for treating post-stroke upper limb spasticity.

METHODS

In total, 196 stroke patients with moderate to severe upper limb spasticity were randomly assigned to either Neuronox or BOTOX intervention. The wrist flexors were mandatory and elbow, finger, and thumb flexors were optional muscles to be injected. Assessments were performed at baseline and 4, 8, and 12 weeks after the intervention. The primary outcome measure was the change from baseline of the Modified Ashworth Scale (MAS) at the wrist flexors at week 4. Secondary outcome measures included the change of MAS at each visit, response rate, Disability Assessment Scale (DAS), Carer Burden Scale, and Global Assessment of treatment benefit.

RESULTS

Primary outcome measures were -1.39±0.79 and -1.56±0.81 in the Neuronox and BOTOX groups, respectively. The difference was within the noninferiority margin of 0.45 (95% upper limit=0.40). There were no significant differences between the groups in the secondary outcome and safety measures, except the change of the MAS at the elbow flexors at week 12 (-0.88±0.75 in the Neuronox group, -0.65±0.74 in the BOTOX group; P=0.0429). Both groups showed significant improvements in the MAS, DAS, and Carer Burden Scale at weeks 4, 8, and 12.

CONCLUSION

Neuronox showed equivalent efficacy and safety compared with BOTOX for treating post-stroke upper limb spasticity.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01313767.

Dysport and Botox at a ratio of 2.5:1 units in cervical dystonia: a double-blind, randomized study

We aimed to compare Dysport (abobotulinumtoxinA, Ipsen Biopharm, Slough, UK) and Botox (onabotulinumtoxinA, Allergan, Irvine, CA, USA) at a 2.5:1 ratio in the treatment of cervical dystonia (CD). A Dysport/Botox ratio of lower than 3:1 was suggested as a more appropriate conversion ratio, considering its higher efficacy and more frequent incidence of adverse effects not only in the treatment of CD but also in other focal movement disorders. A randomized, double-blind, multicenter, non-inferiority, two-period crossover study was done in CD, with a duration of at least 18 months. Patients were randomly assigned to treatment for the first period with Dysport or Botox, and they were followed up for 16 weeks after the injection. After a 4-week washout period, they were switched to the other formulation and then followed up for 16 weeks. The primary outcome was the changes in the Tsui scale between the baseline value and that at 1 month after each injection. A total of 103 patients were enrolled, and 94 completed the study. Mean changes in the Tsui scale between baseline and 4 weeks after each injection tended to favor Botox; however, this was not statistically significant (4.0 ± 3.9 points for the Dysport treatment vs. 4.8 ± 4.1 points for Botox; 95% confidence interval, −0.1-1.7; P = 0.091). The mean change of the Toronto western spasmodic torticollis rating scale score, the proportion of improvement in clinical global impression and patient global impression, and the incidences of adverse events were not significantly different between the two treatments. With regard to safety and efficacy, Dysport was not inferior to Botox in patients with CD at a conversion factor of 2.5:1. [http//clinicaltrial.gov: NCT00950664] © The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.