The evolution of botulinum neurotoxin type A for cosmetic applications

Botulinum toxin-A as a treatment option for refractory idiopathic trigeminal neuralgia of the ophthalmic branch: a case report and literature review

Trigeminal neuralgia is one of the most common neurological pains affecting the head and neck and is associated with severe, lancinating, electrical pain episodes. The maxillary and mandibular branches are usually affected. The ophthalmic branch is rarely involved and, when present, it requires a comprehensive workup to rule out major conditions. Pharmacotherapy and surgery are the most common treatment options for this condition. Systemic medications may pose a wide range of side effects and effectiveness may decrease over time while surgery has inherent complications. Injectable onabotulinum toxins have been utilized for various applications in medicine and dentistry. There is, however, limited data on their use for the management of refractory trigeminal neuralgia of the ophthalmic branch. We present the case of a 58-year-old male diagnosed with refractory idiopathic trigeminal neuralgia affecting the ophthalmic branch, which was unresponsive to standard care and successfully managed with onabotulinum toxin type A. This treatment should be considered in cases of refractory trigeminal neuralgia prior to surgery. We reviewed the relevant literature concerning the application of Onabotulinum toxin A for managing trigeminal neuralgia of the ophthalmic branch. This case report and review aim to enlighten the application of Onabotulinum toxin A for managing refractory trigeminal neuralgia of the ophthalmic branch. Our case report and review show that Onabotulinum toxin A could be used for managing TN of the ophthalmic branch.

Fabrication, characterization and evaluation of a new designed botulinum toxin-cell penetrating peptide nanoparticulate complex

BACKGROUND

To have a better and longer effect, botulinum neurotoxin (BoNT) is injected several times in a treatment course, which could increase side effects and cost. Some of the most cutting-edge strategies being investigated for proteins to their physiologic targets involve the reformulation of BoNT based on peptide-based delivery systems. For this purpose, cell-penetrating peptides (CPPs) are of particular interest because of their capacity to cross the biological membranes.

OBJECTIVES

A short and simple CPP sequence was used as a carrier to create nanocomplex particles from BoNT/A, with the purpose of increasing toxin entrapment by target cells, reducing diffusion, and increasing the duration of the effect.

METHOD

CPP-BoNT/A nanocomplexes were formed by polyelectrolyte complex (PEC) method, considering the anionic structure of botulinum toxin and the cationic CPP sequence. The cellular toxicity, and absorption profile of the complex nanoparticles were evaluated, and the digit abduction score (DAS) was used to assess the local muscle weakening efficacy of BoNT/A and CPP-BoNT/A.

RESULTS

The provided optimized polyelectrolyte complex nanoparticles had a 244 ± 20 nm particle size and 0.28 ± 0.04 PdI. In cellular toxicity, CPP-BoNT/A nanocomplexes as extended-release formulations of BoNT/A showed that nanocomplexes had a more toxic effect than BoNT/A. Furthermore, the comparison of weakening effectiveness on muscle was done among nanoparticles and free toxin on mice based on the digit abduction score (DAS) method, and nanocomplexes had a slower onset effect and a longer duration of action than toxin.

CONCLUSION

Using PEC method allowed us to form nanocomplex from proteins, and peptides without a covalent bond and harsh conditions. The muscle-weakening effect of toxin in CPP-BoNT/A nanocomplexes showed acceptable efficacy and extended-release pattern.

Outcomes of a regional variant of botulinum toxin type A in the treatment of essential blepharospasm and hemifacial spasms: A retrospective study

Purpose:

The aim of this study was to report the outcomes of a regional variant of botulinum toxin type A (BtA) in essential blepharospasm and hemifacial spasm.

Methods:

The medical records of all patients with facial dystonias, who received at least one dose of BtA between May 2016 and April 2017 were retrospectively evaluated. The pre- and post-injection severity of symptoms, graded using the Jankovic rating system for essential blepharospasm and the Samsung Medical Center grading system for hemifacial spasm, the complications after each sitting, and the mean symptom-free interval were recorded. A correlation analysis was done to identify factors associated with longer symptom-free intervals. A P value < 0.05 was considered statistically significant.

Results:

The mean age at presentation was 56.62 ± 10.56 years. The mean duration of follow-up was 1.86 ± 2.06 years. The modal disease severity reduced from 5 to 0 in essential blepharospasm and from 2 to 0 in hemifacial spasm a week after injection of botulinum toxin. The mean symptom-free intervals with doses of 20, 22.5, 25, 30, and 50 units were 102.1 ± 44.7, 132.4 ± 35.3, 147.2 ± 61.6, 124.4 ± 55.1, and 142.4 ± 59.7 days, respectively. The commonest complication was lagophthalmos (26.3%; n = 20). Injections for primary dystonias were associated with longer disease-free intervals than those for secondary dystonias (P = 0.02). In nine sittings, the dose was increased for increased severity or presumed resistance, which resulted in a significant increase in the symptom-free interval (P = 0.004) without an increased incidence of complications (P = 0.48).

Conclusion:

BtA is safe and effective in the treatment of facial dystonias. The drug is more efficacious for primary facial dystonias.

A Novel OnabotulinumtoxinA Treatment Technique to Obtain Predictable Outcomes in Eyebrow Position and Shape

Background

OnabotulinumtoxinA has been approved for multiple clinical and dermatological indications. The toxin, produced by the bacterium Clostridium botulinum, is undoubtedly the most widely used cosmetic treatment for both the reduction and prophylaxis of wrinkles in the upper face and the reshaping of the eyebrows. However, the aesthetic outcomes obtained with respect to eyebrow position and shape are not always predictable and furthermore, untoward effects such as eyelid and brow ptosis are sometimes seen.

Objective

This article suggests a novel injection technique of the upper face with OnabotulinumtoxinA to obtain predictable and reproducible results with respect to eyebrow position and shape, whilst greatly minimizing the risk of adverse effects such as brow and lid ptosis.

Discussion

OnabotulinumtoxinA inhibits the release of acetylcholine and results in the temporary paralysis of skeletal muscle. The aesthetic outcome of wrinkle reduction typically lasts for a period of 14–16 weeks. Although relatively safe in that the toxin does not have any irreversible side effects, even a temporary untoward reaction may be seriously distressing to the cosmetic patient.

Conclusion

The proposed injection technique, when diligently followed, ensures that the final eyebrow position is pleasing and symmetrical with a negligible risk of any untoward effects.

Neurotoxin Impurities: A Review of Threats to Efficacy

Recently launched esthetic botulinum toxin serotype A (BoNT/A) products include Nabota/Jeuveau, Meditoxin/Neuronox, and Botulax, which contain nontoxic accessory proteins and excipients. Clinical evidence supporting these formulations, including their purity and potential immunogenicity or their link to treatment failures, is limited. Any nonhuman protein, including nontoxin accessory proteins, can initiate immune reactions, especially if administered repeatedly, yet the issue of BoNT/A-induced immunogenicity is widely contested. However, there have been multiple reports of treatment failures and observations of BoNT/A-induced neutralizing antibodies. Compared with the purified formulation in Xeomin, these recently launched toxins contain higher total neurotoxin quantities, much of which is inactive and exposes patients to potentially immunogenic nontoxin proteins or inactive neurotoxins that increase their risk of developing treatment failure. Well-established products [especially abobotulinumtoxinA (Dysport), onabotulinumtoxinA (Botox) and Xeomin] are accompanied by comprehensive and long-ranging clinical evidence on safety and efficacy in esthetic facial indications, which still remains undisclosed for many of the recently introduced toxins. Clinicians need this information as patients will require repeated BoNT treatments and may be unnecessarily but cumulatively exposed to potential immunogens. To underscore the need for caution and further evidence, we review some of the issues surrounding BoNT/A-induced immunogenicity and antibody-induced treatment failures and argue that using highly purified toxins that do not negatively impact patient outcomes is a prudent clinical decision.

Rapid and Sensitive Nano-Immunosensors for Botulinum

Botulinum is a deadly bacterial toxin that causes neuroparalytic disease. However, appropriate tools to detect trace toxic proteins are scarce. This study presents a bead-based diffusometric technique for the rapid, simple, and quantitative detection of biological toxins. Functionalized particles called nano-immunosensors were fabricated by forming sandwiched immunocomplexes comprising Au nanoparticles (AuNPs), toxic proteins, and antibodies on fluorescent probe particles. Particle diffusivity tended to decline with increasing concentration of the target proteins. Calibration curves of purified botulinum toxins (0.01-500 ng/mL) were obtained from whole milk and bovine serum, and results suggested that measurement was independent of the background matrix. The activity of botulinum toxin was evaluated by coating synaptosomal-associated protein 25 (SNAP-25) on fluorescent probe particles. AuNP-conjugated antibodies attached to the probe particles when SNAP-25 proteins were cleaved by active botulinum. Thus, toxicity could be detected from slight changes in diffusivity. A short measurement time of 2 min and a limit of detection of 10 pg/mL were achieved. The nano-immunosensors demonstrated rapid biosensing capability and met the demands of onsite screening for food safety, medical instrument hygiene, and cosmetic surgery products.

Comparison of the Clinical Efficacy of Abobotulinumtoxin A (ABO) and Onabotulinumtoxin A (ONA) in the Treatment of Crow's Feet Wrinkles: A Split-Face Study

PURPOSE

Comparing the clinical efficacy of Abobotulinumtoxin A (ABO) and Onabotulinumtoxin A(ONA) using a dosing ratio of 2.5U:1.0U in the treatment of crow's feet wrinkles.

SUBJECTS AND METHODS

A single-blinded, randomized, split-face study, included 40 subjects, with moderate-to-severe crow's feet wrinkles. Patients were subjected to a dose equivalence of (ABO):(ONA); 2.5:1.0 U. Post treatment evaluation was done on 7, 30, and 120 days, comparing: Time, Duration, and Degree of Improvement; Patients Satisfaction.

RESULTS

No significant difference was found between ABO & ONA regarding duration and time to improvement on static posture. While on dynamic posture, ABO showed significantly less time and longer duration. Both products produced highly significant improvement of the wrinkles' severity on both static and dynamic posture in comparison to the baseline severity. Satisfaction was more with ABO.

CONCLUSION

ABO is a safe, effective alternative to ONA in treating crow's feet wrinkles.

Adverse Events of Botulinum Toxin Type A in Facial Rejuvenation: A Systematic Review and Meta-Analysis

BACKGROUND

Botulinum toxin A (BTX-A) is a medical product that is used widely in cosmetics, and concern over the safety profile has increased among injectors and patients.

OBJECTIVE

The purpose was to enhance the statistical effect size using a meta-analysis to detect the incidence rate of adverse events (AEs) in the treatment of facial wrinkles.

METHODS

A systematic search was performed for randomized, double-blind, placebo-controlled trials published through July 2015.

RESULTS

We searched 16 trials, including 42,405 individual participants, and found that in all enrolled facial rejuvenation studies, patients in the BTX-A group had significantly more AEs than those patients in the placebo group (RR = 1.24; 95 % CI 1.07-1.43; p = 0.003). For crow's feet lines injection analysis, the BTX-A group did not exhibit any significant increase in AEs compared with the control group (RR = 1.19; 95 % CI 0.96-1.48; p = 0.12), except in injection site hematoma (RR = 2.14; 95 % CI 1.13-4.07; p = 0.02) in the treatment group. For frown wrinkle injection analysis, AEs were significantly observed in the BTX-A group (RR = 1.47; 95 % CI 1.23-1.77; p < 0.0001), particularly headaches (RR = 1.53; 95 % CI 1.15-2.03; p = 0.003), eyelid ptosis (RR = 5.56; 95 % CI 1.68-18.38; p = 0.005), and heavy eyelids (RR = 6.94; 95 % CI 1.27-37.93; p = 0.03).

CONCLUSION

This meta-analysis confirmed the safety profile of BTX-A for glabellar and crow's feet lines, and BTX-A usage for the removal of upper facial wrinkles, which have some significant mild-to-moderate adverse profiles, including headache, eye disorder, eyelid ptosis, and heavy eyelids. Facial injectors should abide by the technical standards of neurotoxic drugs and be familiar with the local pharmacological effects to lessen the severe side effects.

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 A5 online Instructions to Authors www.springer.com/00266 .

Experiences with CPP-Based Self Assembling Peptide Systems for Topical Delivery of Botulinum Toxin

Considerations in rational designs of CPP-based transcutaneous delivery systems are described. Impact of design considerations of nonclinical and clinical results are presented in detail.

[Management and prevention of adverse events in esthetic interventions]

BACKGROUND

Esthetic interventions are an integral part of today's dermatology. A plethora of novel agents and techniques is currently being launched on the market accompanied by a variety of side effects.

METHOD

We summarize the most common adverse events of fillers, laser treatments, and injection of botulinum toxin and present feasible means of prevention and management.

RESULTS

The profile of adverse events is more favorable in temporary fillers such as hyaluronic acid than in permanent ones. The most common filler-related adverse events include changes of skin color and unspecific swelling. Neural and vascular dysfunctions are observed less frequently, but may result in severe tissue necrosis or loss of vision. Undesirable events of laser treatments largely depend on the applied modality, localization, and indication. Local effects comprise erythema, swelling, crusting, blister formation, and weeping in extreme cases. The formation of laser-induced scarring is more likely to occur in lasers with high energies. Most adverse events of botulinum toxin are mild and transient. Pain and redness around the sites of injection are common. However, a poor injection technique and injection of too many units can trigger major motoric impairment with ptosis and dysarthria.

CONCLUSION

Excellent results can be achieved with esthetic interventions. To guarantee a maximum amount of safety and to minimize risks it is of paramount importance to work with clear indications and respect contraindications. It is important to recognize early adverse events to achieve satisfactory results and avoid severe complications.

Report of Allergic Reaction After Application of Botulinum Toxin

Botulinum toxin is a widely used treatment with satisfactory results, and it is relatively safe in the doses used for cosmetic procedures. The authors report a case of allergic reaction to Chinese botulinum toxin serotype A (CBTX-A). Although this is a rare adverse event, it is nonetheless clinically relevant to healthcare professionals. A 44-year-old woman presented to the authors' hospital complaining of dynamic wrinkles. CBTX-A was used to treat her. Minutes after application, she developed urticarial plaques proximal to the injection site. The patient had an allergic reaction, as documented by a positive skin test, which was controlled by the administration of antihistamines and systemic corticosteroids. This report is intended to guide healthcare professionals faced with this type of adverse event regarding how to proceed without hindering the delivery and effectiveness of the treatment. When performed by a qualified health professional, this treatment brings excellent results in the vast majority of cases.

LEVEL OF EVIDENCE

5 Risk.

Botulinum toxin in the management of blepharospasm: current evidence and recent developments

Blepharospasm is a focal (although usually bilateral) dystonia of the orbicularis oculi muscles, producing excessive eye closure. This produces significant disability through functional blindness. Botulinum neurotoxins (BoNT) have become the treatment of choice for blepharospasm; the impressive response rate and the tolerable safety profile have been proven through multiple clinical studies. There are currently four BoNT approved in the United States for different indications - we review the data on blepharospasm for each of these drugs. Currently, incobotulinumtoxinA and onabotulinumtoxinA have the most evidence of benefit for patients with blepharospasm. Current evidence, recent development and future directions are discussed.

Aesthetic uses of the botulinum toxin

The cosmetic use of botulinum toxin (BoNT) is the most common cosmetic procedure performed in the world today. Common adverse events seen in the aesthetic use of the BoNT include swelling, localized bruising, headaches, injection site discomfort, excessive muscle weakness, and unintended paresis of adjacent muscles. BoNT has a wide array of cosmetic uses, including treatment of glabellar lines, chemical browlift, forehead wrinkles, periorbital, and perioral lines. The future formulations and applications of BoNT type A will be plentiful, and are exciting to consider.

[Botulinum toxin in dermatology]

Treatment with botulinum toxin (BTX) type A has become increasingly important in various clinical areas in dermatology. Particularly popular is the therapy with BTX for hyperkinetic lines associated with muscles of facial expression in aesthetic dermatology, which is the most frequent wrinkle treatment undertaken worldwide. Therapy with BTX also ranks high in curative dermatology. Injections with BTX are the most effective nonoperative therapy for hyperhidrosis. Common indications for the treatment of hyperkinetic lines with BTX are presented in this publication. Therapy of glabellar lines, which has received regulatory approval, is presented in detail. In the second part, treatment of focal hyperhidrosis with emphasis on axillary hyperhidrosis is addressed. In the hand of the experienced practitioner, treatment with BTX in a suitable area of indication is a very safe and effective procedure that leads to remarkable treatment results, associated with a very high patient satisfaction.

Nonclinical and clinical experiences with CPP-based self-assembling peptide systems in topical drug development

Considerations in rational designs of CPP-based transcutaneous delivery systems are described. Impact of design considerations of nonclinical and clinical results are presented in detail.

Botulinum toxin in facial rejuvenation: an update

Since its initial approval by the US Food and Drug Administration (FDA) 20 years ago for the treatment of strabismus, hemifacial spasm, and blepharospasm in adults, botulinum toxin (BTX) has become one of the most frequently requested products in cosmetic rejuvenation around the world. After years of clinical success and consistent safety in the upper face, the use of BTX has expanded and evolved to include increasingly complicated indications. In the hands of adept injectors, the focus has shifted from the treatment of individual dynamic rhytides to shaping, contouring, and sculpting, alone or in combination with other cosmetic procedures, to enhance the aesthetic appearance of the face. Although recent reports have questioned the safety of BTX, 25 years of therapeutic and over 20 years of cosmetic use has demonstrated an impressive record of safety and efficacy when used appropriately by experienced injectors.

Treatment of glabellar lines with botulinum toxin type A (Speywood Unit): a clinical overview

Azzalure (Galderma) is a newly approved European botulinum neurotoxin type A (BoNT-A) specifically designed for aesthetic usages. It is sourced from Dysport (Ipsen Ltd.), which has a 20-year product consistency and has been used widely for various therapeutic and aesthetic applications. Azzalure and Dysport are collectively referred to as BoNT-A (Speywood Unit; s.U) (or abobotulinumtoxinA in the U.S.) after their biological activity unit, which is unique and not interchangeable with units of other commercial BoNT-A preparations. Azzalure is approved for the treatment of moderate-to-severe glabellar lines, with a total dose of 50 s.U distributed evenly among 5 injection points. To ensure optimal treatment outcomes with BoNT-A (s.U), it is crucial for injectors to adopt proper methods of reconstitution and injection, which can be acquired through training. We review here the method of reconstitution for BoNT-A (s.U), as well as the injection dose, points and techniques for glabellar line treatment. We also review the efficacy and safety results of BoNT-A (s.U) demonstrated in 11 clinical studies, most of which were randomized, double-blind and placebo-controlled. The studies included assessments after single injections as well as after up to 6 repeated treatment sessions. We summarize the clinical efficacy results, which include the responder rate 1 month post-injection, onset of response and duration of action, as well as safety results, which include incidence of treatment-emergent adverse events and specifically eyelid ptosis. The efficacy and safety profiles reported here are unique to BoNT-A (s.U) and cannot be generalized to other BoNT-A products.