Overview of DaxibotulinumtoxinA for Injection: A Novel Formulation of Botulinum Toxin Type A

Reply to Trosch et al. Comment on "Dashtipour et al. Dysphagia and Muscle Weakness Secondary to Botulinum Toxin Type A Treatment of Cervical Dystonia: A Drug Class Analysis of Prescribing Information. Toxins 2024, 16, 442"

We thank Trosch et al [...].

Influence of the cosmetic use of botulinum toxin type a on temperature measurements using infrared thermography

This study aims to assess the influence of the cosmetic use of Botulinum toxin type A (BTX-A) on temperature measurements using Infrared thermography (IT). A quantitative cross-sectional study was conducted with 16 patients to examine the cosmetic application of BTX-A in the upper third of the face to treat dynamic wrinkles (expression lines). The substance used in the patients was Botulinum Toxin type A DYSPORT® 500 IU. A thermogram in frontal norm was acquired from each patient in three different moments: (M1) before BTX-A application, (M2) 10 min after BTX-A application, and (M3) five days after BTX-A application. The ROIs were demarcated in each image with a diameter of 10 mm, and then the average temperature values of each ROI were recorded. Mixed ANOVA, with Tukey's post hoc test, was used to determine interactions between factors in the dependent variable. The paired T-test was used to assess whether the mean temperatures on the face's right and left sides were statistically different. The significance level was set at 5%, considering p < 0.05. For the left-side temporal ROI, statistically significant differences were observed only between the different assessed times (p = 0.010). Considering the mean temperature difference, at the temporal ROI, a reduction of the M2 temperature was observed (ΔT = 0.3 ℃) and an increase at M3 (ΔT = 0.6 ℃). The cosmetic use of BTX-A may alter skin temperature values assessed using IT, and this effect can last for days.

Peptide-Bound Aflibercept Eye Drops for Treatment of Neovascular Age-Related Macular Degeneration in Nonhuman Primates

The advent of biomacromolecules antagonizing vascular endothelial growth factor (VEGF) has revolutionized the treatment of neovascular age-related macular degeneration (nAMD). However, frequent intravitreal injections of these biomacromolecules impose an enormous burden on patients and create a massive workload for healthcare providers. This causes patients to abandon therapy, ultimately leading to progressive and irreversible vision loss. In order to address this unmet clinical need, a noninvasive treatment for nAMD is developed. An optimized cell-penetrating peptide derivative, bxyPenetratin (bxyWP), is used to non-covalently complex with the anti-VEGF protein aflibercept (AFL) via reversible hydrophobic interaction. The interaction is crucial for AFL delivery, neither impairing the affinity of AFL to pathological VEGF, nor being interfered by endogenous proteins in tear fluids. AFL/bxyWP eye drops exhibit prolonged retention on the eye and excellent absorption into the posterior ocular segment following topical administration, with significant drug distribution to the retina and choroid. In a laser-induced choroidal neovascularization model on cynomolgus monkeys, AFL/bxyWP eye drops efficiently reduce lesion size and leakage comparable to conventional intravitreal injection of AFL. These results suggest that AFL/bxyWP eye drops are feasible self-administered treatment for neovascular retinal diseases and potentially become a substitute for intravitreal injections.

Successful Treatment of Severe, Poorly Controlled Benign Essential Blepharospasm with DaxibotulinumtoxinA

Benign essential blepharospasm is a focal dystonia characterized by involuntary contractions of the orbicularis oculi. Botulinum toxin type A injections are often first-line treatment, but patients may experience refractory symptoms or decreased response over time. DaxibotulinumtoxinA, a novel botulinum toxin type A product, has shown promise in cervical dystonia and facial rhytids but has not been previously reported for benign essential blepharospasm treatment. This case highlights a 57-year-old male with severe, poorly controlled benign essential blepharospasm despite high-dose injections of onabotulinumtoxinA and incobotulinumtoxinA. He subsequently received 100 units of daxibotulinumtoxinA in the same periorbital injection pattern with subjective faster onset, extended duration of effect, and improved symptom management compared to previous treatments. Notably, the patient experienced 50% to 75% efficacy retention at 3 months postinjection, significantly better than his response to other botulinum toxin type A products. This case suggests that daxibotulinumtoxinA may be an effective treatment for benign essential blepharospasm including patients experiencing poor symptom control with other botulinum toxin type A products.

Excitation-contraction coupling inhibitors potentiate the actions of botulinum neurotoxin type A at the neuromuscular junction

BACKGROUND AND PURPOSE

Botulinum neurotoxin type A1 (BoNT/A) is one of the most potent neurotoxins known. At the same time, it is also one of the safest therapeutic agents used for the treatment of several human disorders and in aesthetic medicine. Notwithstanding great effectiveness, strategies to accelerate the onset and prolong BoNT/A action would significantly ameliorate its pharmacological effects with beneficial outcomes for clinical use.

EXPERIMENTAL APPROACH

Here, we combined BoNT/A with two fast-acting inhibitors of excitation-contraction coupling inhibitors (ECCI), either the μ-conotoxin CnIIIC or dantrolene, and tested the effect of their co-injection on a model of hind-limb paralysis in rodents using behavioural, biochemical, imaging and electrophysiological assays.

KEY RESULTS

The BoNT/A-ECCI combinations accelerated the onset of muscle relaxation. Surprisingly, they also potentiated the peak effect and extended the duration of the three BoNT/A commercial preparations OnabotulinumtoxinA, AbobotulinumtoxinA and IncobotulinumtoxinA. ECCI co-injection increased the number of BoNT/A molecules entering motoneuron terminals, which induced a faster and greater cleavage of SNAP-25 during the onset and peak phases, and prolonged the attenuation of nerve-muscle neurotransmission during the recovery phase. We estimate that ECCI co-injection yields a threefold potentiation in BoNT/A pharmacological activity.

CONCLUSIONS AND IMPLICATIONS

Overall, our results show that the pharmacological activity of BoNT/A can be combined and synergized with other bioactive molecules and uncover a novel strategy to enhance the neuromuscular effects of BoNT/A without altering the neurotoxin moiety or intrinsic activity, thus maintaining its exceptional safety profile.

DaxibotulinumtoxinA Treatment for Laryngeal Respiratory Dystonia

BACKGROUND

Laryngeal respiratory dystonia (LRD) is diagnosed based on clinical presentation, patient history, and physical examination. Key indicators include dyspnea, desynchronized breathing patterns, and laryngoscopic findings that reveal vocal fold adduction during inspiration. Treatment for LRD remains controversial and often yields limited effectiveness. While botulinum toxin type A (BtxA) is commonly injected into the thyroarytenoid-lateral cricothyroid (TA-LCA) muscle complex, there are cases where injections into the interarytenoid (IA) muscle have also proven beneficial. DaxibotulinumtoxinA (DAXI) is an emerging therapy that has shown promising effectiveness and safety across various conditions, including cervical dystonia. In this report, we present the first documented use of DAXI specifically for LRD, highlighting the significant benefits experienced by the patient compared to previous treatments with BtxA.

CASE

A 77-year-old man presented with a 1-year history of significant shortness of breath. Laryngeal endoscopy demonstrated inappropriate adduction of the patient's vocal folds during respiration, suggestive of LRD. The patient received their first Botox (BtxA) injection in May 2018 and has since undergone a total of 40 injections. The patient had a variable response to BtxA injection into his TA-LCA muscle complex, experiencing general improvement in breathing but frequent negative impact on voice and swallowing function. In November of 2021, electromyography-guided BtxA injection into the patient's IA muscle was performed with significant improvement in results. The patient described near-complete resolution of his LRD breathing symptoms with minimal voice changes and a duration of benefit of ~50 days. In November of 2023, DAXI injection into the patient's IA muscle was performed. The patient self-reported a complete resolution of his symptoms for a total duration of benefit of 91 days. Subsequent injections with DAXI in February and May of 2024 had near identical responses.

CONCLUSION

DAXI appears to provide ~80% better duration than the patient's average BtxA injection and a 57% improvement than his best BtxA injection. DAXI is a safe and realistic alternative to BtxA injection in patients with LRD.

Innovation in Botulinum Toxins

This study aims to analyze and discuss recent trials of high-dose and liquid toxins for treating moderate to severe glabellar lines. A comprehensive review of clinical studies and patient outcomes data was conducted to assess the effectiveness and safety profiles of high-dose and liquid toxins. Clinical studies have demonstrated that high-dose toxins provide prolonged muscle relaxation and reduced wrinkles, with well-tolerated safety profiles. Liquid toxins offer comparable efficacy to traditional formulations with quicker onset and extended duration of effects. The introduction of high-dose and liquid toxins represents a significant advancement in esthetic medicine, providing patients with more options for achieving natural-looking, long-lasting results.

The recent development, application, and future prospects of muscle atrophy animal models

Muscle atrophy, characterized by the loss of muscle mass and function, is a hallmark of sarcopenia and cachexia, frequently associated with aging, malignant tumors, chronic heart failure, and malnutrition. Moreover, it poses significant challenges to human health, leading to increased frailty, reduced quality of life, and heightened mortality risks. Despite extensive research on sarcopenia and cachexia, consensus in their assessment remains elusive, with inconsistent conclusions regarding their molecular mechanisms. Muscle atrophy models are crucial tools for advancing research in this field. Currently, animal models of muscle atrophy used for clinical and basic scientific studies are induced through various methods, including aging, genetic editing, nutritional modification, exercise, chronic wasting diseases, and drug administration. Muscle atrophy models also include in vitro and small organism models. Despite their value, each of these models has certain limitations. This review focuses on the limitations and diverse applications of muscle atrophy models to understand sarcopenia and cachexia, and encourage their rational use in future research, therefore deepening the understanding of underlying pathophysiological mechanisms, and ultimately advancing the exploration of therapeutic strategies for sarcopenia and cachexia.

DaxibotulinumtoxinA for injection to treat moderate or severe glabellar lines: A randomized, multicenter, Phase III, double-blind, placebo-controlled trial in China

BACKGROUND

DaxibotulinumtoxinA for injection (DAXI), a novel botulinum toxin type A formulation, is FDA-approved for glabellar lines treatment. Its clinical efficacy has been demonstrated in two Phase III trials (SAKURA 1 and SAKURA 2).

OBJECTIVE

To evaluate DAXI efficacy and safety in Chinese adults with moderate/severe glabellar lines.

METHODS

In this Phase III, randomized (2:1), double-blind trial, Chinese adults with moderate/severe glabellar lines received 40 U DAXI or placebo into the corrugator muscles bilaterally and the procerus. Glabellar line severity was evaluated by investigators (Investigator Global Assessment-Frown Wrinkle Severity [IGA-FWS] scale) and participants (Patient Frown Wrinkle Severity [PFWS] scale) for ≥24 to 36 weeks. The primary endpoint was the proportion of 2-point composite responders achieving ≥2-point reduction in IGA-FWS and PFWS scores at week 4 post-treatment.

RESULTS

Overall, 307 participants received treatment (DAXI, 205; placebo, 102). A significantly greater proportion of participants in the DAXI arm vs the placebo arm achieved a 2-point composite response at week 4: 125 (61.0%) vs 1 (1.0%); difference, 60.0% [95% CI 49.40-66.46]; 2-sided p < 0.0001). At week 4, 94.1% of the DAXI-treated participants achieved an IGA-FWS score 0/1 (none/mild) and 86.3% achieved PFWS 0/1; median time to loss of none/mild on IGA-FWS and PFWS was 23.9 weeks. The benefits of DAXI over placebo through week 24 occurred regardless of the baseline IGA-FWS score, prior botulinum toxin type A (BoNTA) exposure, sex or age. DAXI was well tolerated with no new safety signals.

CONCLUSION

DAXI provided durable efficacy and acceptable safety for treating moderate/severe glabellar lines in Chinese participants.

Zinc in Dermatology: Exploring Its Emerging Role in Enhancing Botulinum Toxin Formulations and Clinical Efficacy

This literature review provides a novel exploration of zinc's multifaceted roles in dermatology, with a particular focus on its potential integration into botulinum toxin formulations-an area that remains relatively underexplored in clinical practice. Zinc is widely recognized for its critical functions in skin health, including morphogenesis, regeneration, and protection, and its use in aesthetic medicine offers a unique opportunity for innovation. Specifically, incorporating zinc into botulinum toxin formulations could enhance the efficacy and stability of these treatments. Although zinc has historically been used in topical dermatological products and systemic health interventions, its potential in cosmetic preparations, such as anti-aging therapies or non-invasive aesthetic treatments, remains under-researched. Emerging patents suggest promising formulations combining zinc with botulinum toxin that may improve product stability and extend therapeutic effects. While current studies on oral zinc supplementation present mixed results concerning its ability to prolong botulinum toxin effects, this underscores the need for more rigorous investigation in the realm of aesthetic medicine. Zinc's well-established role in stabilizing dermatological products, such as sunscreens, and its applications in wound healing and skin regeneration, further highlights its potential for broader therapeutic uses beyond cosmetic applications. This review identifies a critical gap in the literature and calls for future research to optimize zinc concentrations and delivery methods specifically for aesthetic medical procedures, offering new insights into improving dermatological treatments beyond the scope of traditional cosmetic preparations.

Dysphagia and Muscle Weakness Secondary to Botulinum Toxin Type A Treatment of Cervical Dystonia: A Drug Class Analysis of Prescribing Information

The first-line management of cervical dystonia (CD) symptoms is intramuscular injection of botulinum toxin type A (BoNTA). However, a comparison of safety among BoNTAs is difficult because, per regulatory authorities, units of BoNTA activity are not interchangeable. Dysphagia and muscle weakness are widely considered two key adverse events to monitor closely in the treatment of CD. This integrated analysis compared the safety of BoNTAs approved for CD in the US by evaluating relationships between the incidence of dysphagia and muscle weakness in prescribing information and the core neurotoxin content. Coefficients The coefficients of determination (R2) and trendlines were estimated via regression-based lines of best fit. Adverse drug reaction (ADR) rates were strongly correlated with core neurotoxin amounts for conventional BoNTAs (slope coefficients: dysphagia = 0.048, R2 = 0.74; muscle weakness = 0.096, R2 = 0.82). The published ADR rates at approved doses for conventional BoNTAs were higher compared with DaxibotulinumtoxinA (DAXI; DAXXIFY®, Revance Therapeutics, Inc., Nashville, TN, USA) by core neurotoxin content. The use of a core neurotoxin amount was found to be an effective method for comparing the safety of BoNTA products. Current clinical trials suggest that DAXI, a novel BoNTA formulation, provides a potentially wider safety margin compared with other approved BoNTAs for CD. The lower amount of core neurotoxin administered at approved doses compared with conventional BoNTAs may explain low on-target ADRs like muscle weakness, whereas reduced diffusion from the injection site is thought to be responsible for low off-target ADRs like dysphagia.

The Efficacy of Botulinum Toxin Type A (BTA) in the Treatment of Hypertrophic Scars and Keloids: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Hypertrophic scars cause significant physical and emotional discomfort. Botulinum toxin type A (BTA) has shown promising outcomes in reducing scar formation. Research suggested its effectiveness in managing hypertrophic scars and keloids. This systematic review and meta-analysis were reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, including randomized controlled trials (RCTs). The included studies involved patients with hypertrophic scars treated with BTA. Five databases were searched from inception to August 2024. Studies were screened and selected by two independent reviewers. Data on study design, patient demographics, and interventions was extracted. The risk of bias (ROB) was assessed using the ROB revised tool developed by Cochrane (ROB2). Meta-analysis was performed using RevMan Web (The Cochrane Collaboration, London, UK) with a random-effects model due to high heterogeneity, calculating mean differences for the primary and secondary outcomes. Outcomes included Vancouver Scar Scale (VSS) scores, scar thickness, vascularity, pliability, and pigmentation. The systematic review identified 182 records from five databases. The screening process resulted in seven studies included in the final analysis after assessment for eligibility. The efficacy of BTA in treating hypertrophic scars and keloids was assessed. The meta-analysis showed that BTA significantly improved VSS scores, with a pooled mean difference of -1.69 (P = 0.01). However, BTA did not show a statistically significant effect on reducing scar height/thickness or improving vascularity. Scar pliability was significantly improved by BTA, with a pooled mean difference of -0.76 (P = 0.002), while there was no significant effect on pigmentation. High heterogeneity was observed across the studies. BTA could be used as an effective treatment for the components of hypertrophic scars and keloids, especially regarding their pliability and improving scar quality. However, for functions such as the change in scar height, vascularity, and pigmentation, more research is still required among larger RCTs. Future research should focus on refining the treatment regimens and the mode of action of BTA to the scar tissue.

The effect of rectus femoris transfer on kinematics and functional outcomes in adult stroke patients walking with a stiff knee gait

BACKGROUND

Stiff knee gait is characterized by a reduced peak knee flexion during swing. Overactivity of the rectus femoris is often cited as a main cause for stiff knee gait. Little is known about the effect of an isolated rectus femoris transfer treatment on kinematic and functional outcomes in a group of stroke survivors.

OBJECTIVE

To perform an experimental study to evaluate the effect of an isolated rectus femoris transfer on knee and hip kinematics and functional outcomes in adult stroke patients walking with a stiff knee gait.

METHOD

In this experimental study, 10 stroke survivors were included. During the surgical procedure, the distal rectus femoris tendon of the affected side was transferred to the medial knee flexors to improve knee flexion during swing. Knee and hip kinematics and a variety of functional outcomes were measured within 3 weeks before surgery and between 6 and 7 months after the surgery.

RESULTS

We found a statistically significant improvements in peak knee flexion during swing and knee range of motion of 10.6° (sd 4.7, p=0.000) and 10.5° (sd 6.2, p=0.001) post-surgery, respectively. Hip kinematics showed no significant differences. In addition, we found statistically significant improvements on the 6-minute walk test (42.5, sd 36.7, p=0.008), 10-meter walk test (1.26, sd 1.4, p=0.030), Timed up-and-go test (1.34, sd 1.18, p=0.009), L-test (2.97 sd 2.85, p=0.014) and on a subjective BORG scoring of foot clearance (1.8, sd 0.6, p=0.006). No significant differences were found on other measured functional outcomes.

CONCLUSIONS

Rectus femoris transfer is a valuable treatment option for stroke patients walking with a stiff knee gait to improve knee kinematics and a selection of functional outcomes. There are no detrimental side effects on hip kinematics.

Immunogenicity of Botulinum Toxin Type A in Different Clinical and Cosmetic Treatment, a Literature Review

BACKGROUND

Botulinum toxin type A is widely utilized for both therapeutic and aesthetic purposes, yet concerns regarding its immunogenicity have raised issues related to treatment failure and adverse reactions.

OBJECTIVE

This review aims to evaluate the immunogenicity of commercially available botulinum toxin type A products across various clinical indications and identify the risk factors associated with antibody formation.

METHODS

A comprehensive search of electronic databases was conducted to find studies that investigated the immunogenicity of botulinum toxin type A in patients treated for different conditions. The studies were classified based on the Oxford Center for Evidence-Based Medicine's evidence hierarchy.

RESULTS

The overall incidence of neutralizing antibody formation with botulinum toxin type A treatment is relatively low. However, it varies depending on the indication and is influenced by factors such as the frequency of injections and the cumulative dose. The total cumulative dose and the number of treatment cycles are critical factors in determining the risk of developing antibodies against botulinum toxin type A.

CONCLUSION

This literature review highlights that the immunogenicity of botulinum toxin type A products differs across indications, with repeated injections posing a significant risk for the formation of neutralizing antibodies. The findings underscore the need for further research to better understand antibody formation mechanisms and to develop strategies that minimize their impact on treatment efficacy.

Clinical Benefits of DaxibotulinumtoxinA for Injection: Beyond Glabellar Line Effacement?

BACKGROUND

Botulinum toxin type A (BoNTA) is standard of care for glabellar lines ameliorization. DaxibotulinumtoxinA for Injection (DAXI) is a new BoNTA with a unique formulation representing the latest advancement in BoNTA technology. There is an unmet need for patients to understand the full potential of BoNTA treatment and new technologies.

OBJECTIVE

To update clinical data supporting the use of DAXI for glabellar lines within the context of clinical experience.

MATERIALS AND METHODS

A narrative review of the literature and summary of clinical experience with DAXI.

RESULTS

The DAXI clinical trial program reflects clinical experience post-FDA approval, with DAXI demonstrating rapid onset, high patient response rates, and extended treatment duration versus conventional BoNTAs. Clinical observations suggest that DAXI has limited diffusion from the injection site, enabling more localized control of muscle activity and greater improvements in wrinkle severity. DAXI enables practitioners to exert greater finesse in their injections and in predicting changes to eyebrow shape and position and achieve improvement in skin quality.

CONCLUSION

Advances in BoNTA technology can provide patients with greater options for treatment outcomes. The potential for enhanced localized effects with DAXI may contribute to more precise and targeted effects on muscle activity and additional aesthetic benefits to patients.

Clinical effect of botulinum toxin type A combined with autologous fat grafting in patients with nasolabial fold depression

BACKGROUND

Nasolabial fold (NLF) depression can affect the facial appearance of patients to some extent and increase their psychological burdens. In recent years, autologous fat grafting (AFG) combined with botulinum toxin A (BTX-A) injection (AFG + BTX-A injection) has been gradually applied in the treatment of patients with NLF depression. Although studies have been conducted on the efficacy and safety of AFG + BTX-A injection in treating NLF depression, the experimental design, observational indicators, and sample enrollment criteria vary remarkably, making it difficult to draw convincing and consistent conclusions. Thus, further relevant research is warranted.

AIM

To assess the esthetic improvement, efficacy, and safety of AFG + BTX-A injections in patients with NLF depression.

METHODS

This study included 60 patients with NLF depression who were treated in our hospital from February 2019 to April 2021. These patients were categorized into control (n = 30) and observation (n = 30) groups. The observation group received AFG + BTX-A injection, whereas the control group underwent AFG only. All patients were evaluated using the wrinkle severity rating scale (WSRS) and global aesthetic improvement scale. The compactness of facial contours, skin evaluation indexes, adverse reactions, and satisfaction of the two groups were evaluated 3 months postoperatively.

RESULTS

The WSRS scores of the observation group at 1, 3, and 6 months postoperatively were lower than those of the control group (P < 0.05). Three months postoperatively, facial fine lines and pores showed obvious improvement and the skin index score was higher in the observation group than in the control group (P < 0.05). The compactness of facial contours was better in the observation group than in the control group (P < 0.05). In addition, no remarkable differences were noted in the incidence of postoperative adverse reactions such as facial stiffness, facial asymmetry, facial bruising, and facial concavity inequality (P > 0.05).

CONCLUSION

AFG + BTX-A injection is a highly safe, cost-effective, effective, and long-lasting treatment for NLF depression with high esthetic value, which should be promoted in the future.

Update on Non-Interchangeability of Botulinum Neurotoxin Products

The growing use of botulinum neurotoxins (BoNTs) for medical and aesthetic purposes has led to the development and marketing of an increasing number of BoNT products. Given that BoNTs are biological medications, their characteristics are heavily influenced by their manufacturing methods, leading to unique products with distinct clinical characteristics. The manufacturing and formulation processes for each BoNT are proprietary, including the potency determination of reference standards and other features of the assays used to measure unit potency. As a result of these differences, units of BoNT products are not interchangeable or convertible using dose ratios. The intrinsic, product-level differences among BoNTs are compounded by differences in the injected tissues, which are innervated by different nerve fiber types (e.g., motor, sensory, and/or autonomic nerves) and require unique dosing and injection sites that are particularly evident when treating complex therapeutic and aesthetic conditions. It is also difficult to compare across studies due to inherent differences in patient populations and trial methods, necessitating attention to study details underlying each outcome reported. Ultimately, each BoNT possesses a unique clinical profile for which unit doses and injection paradigms must be determined individually for each indication. This practice will help minimize unexpected adverse events and maximize efficacy, duration, and patient satisfaction. With this approach, BoNT is poised to continue as a unique tool for achieving individual goals for an increasing number of medical and aesthetic indications.

Embracing the Versatility of Botulinum Neurotoxins in Conventional and New Therapeutic Applications

Botulinum neurotoxins (BoNTs) have been used for almost half a century in the treatment of excessive muscle contractility. BoNTs are routinely used to treat movement disorders such as cervical dystonia, spastic conditions, blepharospasm, and hyperhidrosis, as well as for cosmetic purposes. In addition to the conventional indications, the use of BoNTs to reduce pain has gained increased recognition, giving rise to an increasing number of indications in disorders associated with chronic pain. Furthermore, BoNT-derived formulations are benefiting a much wider range of patients suffering from overactive bladder, erectile dysfunction, arthropathy, neuropathic pain, and cancer. BoNTs are categorised into seven toxinotypes, two of which are in clinical use, and each toxinotype is divided into multiple subtypes. With the development of bioinformatic tools, new BoNT-like toxins have been identified in non-Clostridial organisms. In addition to the expanding indications of existing formulations, the rich variety of toxinotypes or subtypes in the wild-type BoNTs associated with new BoNT-like toxins expand the BoNT superfamily, forming the basis on which to develop new BoNT-based therapeutics as well as research tools. An overview of the diversity of the BoNT family along with their conventional therapeutic uses is presented in this review followed by the engineering and formulation opportunities opening avenues in therapy.

Three-point Method Nerve Block for Relieving Pain of Microbotox Injection in Middle and Upper Face

Background

With the popularity of microbotox, pain caused by multiple microdroplets and subcutaneous injection of botulinum toxin is increasing. This study presents a new, refined, three-point nerve block technique that provides effective pain relief during minimally invasive injection therapy targeting the middle and upper face.

Methods

Fifty volunteers underwent facial ultrasonography to measure the locations of the supraorbital and infraorbital foramen. Following microdrop Botox injection of the middle and upper face, 100 patients underwent a self-controlled study to analyze whether a three-point nerve block surpasses topical anesthesia for reducing injection pain. The visual analog scale pain score, the time of the three-point method and botulinum toxin injection, and side effects were recorded.

Results

Among the volunteers, the location of the supraorbital and infraorbital foramen showed no statistical difference between the left and right sides. For the 100 patients (13 men, 87 women) who underwent the three-point nerve block, the visual analog scale pain scores on the experimental side were significantly lower than those on the control side, except in the frontotemporal region (2.46 ± 0.50, 2.42 ± 0.47, P > 0.05). The duration of the unilateral three-point nerve block was 74.8 ± 5.64 seconds. The total injection time was 189.86 ± 26.79 seconds (range 148-286 s).

Conclusions

The three-point method exerted prominent analgesic effects during middle and upper facial treatments, with benefits including a precise block region, high satisfaction, and simple operation technique. Therefore, clinicians can easily master and apply this method.

Achieving Durable Forehead Line Outcomes With DaxibotulinumtoxinA: Early Experience in Real-World Clinical Practice

Background

Irrespective of botulinum toxin type A (BoNT-A) product used, differences in duration between the frontalis and glabella can be a challenge. Since the approval of daxibotulinumtoxinA for injection (DAXI, DAXXIFY; Revance, Nashville, TN), injectors have been eager not only to reproduce the durable results observed in the glabella but also to achieve an extended duration in the frontalis.

Objectives

To describe how the author has successfully modified their injection technique to achieve extended DAXI duration in the frontalis.

Methods

In this study, the author presents an approach to obtaining longevity in the forehead with DAXI based on clinical experience performing more than 400 treatments on more than 250 patients with DAXI since product approval.

Results

DAXI has a limited diffusion profile. If patients are not injected in the mid-to-low frontalis directly, compensatory motion of the lower frontalis leads to premature return of movement, which can result in suboptimal DAXI injection and shortened patient-reported duration. With previous generations of BoNT-A products, some degree of migration from the upper frontalis injection sites and/or the glabella injection sites into the mid and low frontalis is sufficient to prevent this effect, but the precision of DAXI demands that these fibers be more deliberately addressed with a larger number of individual injections.

Conclusions

Through the use of more injection points, a wider area of treatment, and customization to fit patient needs, duration similar to that observed in clinical studies (20.9 weeks) can be achieved using between 20% and 33% fewer units of DAXI.

Level of Evidence 4

Research progress in spasmodic torticollis rehabilitation treatment

Spasmodic torticollis (ST) is a focal dystonia that affects adults, causing limited muscle control and impacting daily activities and quality of life. The etiology and curative methods for ST remain unclear. Botulinum toxin is widely used as a first-line treatment, but long-term usage can result in reduced tolerance and adverse effects. Rehabilitation therapy, with its minimal side effects and low potential for harm, holds significant clinical value. This article explores the effectiveness of adjunctive therapies, including exercise therapy, transcranial magnetic stimulation, shockwave therapy, neuromuscular electrical stimulation, vibration therapy, electromyographic biofeedback, and acupuncture, in the treatment of ST. The aim is to provide clinicians with additional treatment options and to discuss the efficacy of rehabilitation therapy for ST.

Efficacy and Safety of DaxibotulinumtoxinA for Injection in Cervical Dystonia: ASPEN-1 Phase 3 Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

ASPEN-1 was a phase 3, randomized, double-blind, placebo-controlled study to evaluate the efficacy, duration of response, and safety of 2 doses of DaxibotulinumtoxinA for Injection (DAXI), a novel botulinum toxin type A formulation in participants with cervical dystonia (CD).

METHODS

Adults (aged 18-80 years) with moderate-to-severe CD (Toronto Western Spasmodic Torticollis Rating Scale [TWSTRS] total score ≥20) were enrolled at 60 sites across 9 countries in Europe and North America. Participants were randomized (3:3:1) to single-dose intramuscular DAXI 125U, 250U, or placebo and followed for up to 36 weeks after injection. The primary end point was change from baseline in TWSTRS total score averaged across weeks 4 and 6. Key secondary end points included duration of effect, Clinical and Patient Global Impression of Change (CGIC, PGIC), TWSTRS subscale scores, and safety. Multiplicity-adjusted intent-to-treat hypothesis tests with multiple imputation were performed using ANCOVA and Cochran-Mantel-Haenszel analyses.

RESULTS

Of 444 individuals screened, 301 were randomized to DAXI 125U (n = 125) or 250U (n = 130) or placebo (n = 46). DAXI 125U and 250U significantly improved the mean TWSTRS total score vs placebo (least squares mean [standard error] difference vs placebo: DAXI 125U, -8.5 [1.93], p < 0.0001; DAXI 250U, -6.6 [1.92], p = 0.0006). The median duration of effect (time from treatment until loss of ≥80% of the peak improvement in average TWSTRS total score achieved at weeks 4 and 6) was 24.0 (95% confidence interval 20.3-29.1) weeks with DAXI 125U and 20.3 (16.7-24.0) weeks with DAXI 250U. Significant improvements were also observed with DAXI in CGIC and PGIC responder rates and TWSTRS subscales. Treatment-related treatment-emergent adverse events (TEAEs) were reported by 29.6% of participants with DAXI 125U, 23.8% with DAXI 250U, and 17.4% with placebo, with injection site pain being the most common overall. The most frequently reported treatment-related TEAEs of interest in DAXI 125U, DAXI 250U, and placebo, respectively, were muscular weakness (4.8%, 2.3%, 0%), musculoskeletal pain (2.4%, 3.1%, 0%), and dysphagia (1.6%, 3.8%, 0%).

DISCUSSION

This study demonstrated that DAXI, at doses of 125U and 250U, is an effective, safe, long-acting, and well-tolerated treatment for CD.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov identifier (NCT03608397, submitted July 11, 2018) and EU Clinical Trials Register (ClinicalTrialsRegister.eu EudraCT identifier 2018-000446-19, submitted September 13, 2018). First participant enrolled on June 11, 2018. Trial registration was performed in accordance with the Food and Drug Administration Amendments Act (FDAAA 801), which stipulates that the responsible party register an applicable clinical trial not later than 21 calendar days after enrolling the first human participant (42 CFR 11.24).

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that in adults with moderate-to-severe idiopathic cervical dystonia, DAXI reduces dystonia more effectively than placebo.

From Toxin to Treatment: A Narrative Review on the Use of Botulinum Toxin for Autonomic Dysfunction

Since its regulatory approval over a half-century ago, botulinum toxin has evolved from one of the most potent neurotoxins known to becoming routinely adopted in clinical practice. Botulinum toxin, a highly potent neurotoxin produced by Clostridium botulinum, can cause botulism illness, characterized by widespread muscle weakness due to inhibition of acetylcholine transmission at neuromuscular junctions. The observation of botulinum toxin's anticholinergic properties led to the investigation of its potential benefits for conditions with an underlying etiology of cholinergic transmission, including autonomic nervous system dysfunction. These conditions range from disorders of the integument to gastrointestinal and urinary systems. Several formulations of botulinum toxin have been developed and tested over time, significantly increasing the availability of this treatment for appropriate clinical use. Despite the accelerated and expanded use of botulinum toxin, there lacks an updated comprehensive review on its therapeutic use, particularly to treat autonomic dysfunction. This narrative review provides an overview of the effect of botulinum toxin in the treatment of autonomic dysfunction and summarizes the different formulations and dosages most widely studied, while highlighting reported outcomes and the occurrence of any adverse events.

Complexing Protein-Free Botulinum Neurotoxin A Formulations: Implications of Excipients for Immunogenicity

The formation of neutralizing antibodies is a growing concern in the use of botulinum neurotoxin A (BoNT/A) as it may result in secondary treatment failure. Differences in the immunogenicity of BoNT/A formulations have been attributed to the presence of pharmacologically unnecessary bacterial components. Reportedly, the rate of antibody-mediated secondary non-response is lowest in complexing protein-free (CF) IncobotulinumtoxinA (INCO). Here, the published data and literature on the composition and properties of the three commercially available CF-BoNT/A formulations, namely, INCO, Coretox® (CORE), and DaxibotulinumtoxinA (DAXI), are reviewed to elucidate the implications for their potential immunogenicity. While all three BoNT/A formulations are free of complexing proteins and contain the core BoNT/A molecule as the active pharmaceutical ingredient, they differ in their production protocols and excipients, which may affect their immunogenicity. INCO contains only two immunologically inconspicuous excipients, namely, human serum albumin and sucrose, and has demonstrated low immunogenicity in daily practice and clinical studies for more than ten years. DAXI contains four excipients, namely, L-histidine, trehalosedihydrate, polysorbate 20, and the highly charged RTP004 peptide, of which the latter two may increase the immunogenicity of BoNT/A by introducing neo-epitopes. In early clinical studies with DAXI, antibodies against BoNT/A and RTP004 were found at low frequencies; however, the follow-up period was critically short, with a maximum of three injections. CORE contains four excipients: L-methionine, sucrose, NaCl, and polysorbate 20. Presently, no data are available on the immunogenicity of CORE in human beings. It remains to be seen whether all three CF BoNT/A formulations demonstrate the same low immunogenicity in patients over a long period of time.

：A retrospective study

Background

It is widely acknowledged that botulinum toxin type A (BTX-A) has been widely used in the treatment of hemifacial spasm (HFS). However, there is currently a lack of systematic analysis of the factors affecting its therapeutic effect. Therefore, this study aims to explore the influencing factors of BTX-A in the treatment of HFS and to identify risk factors for poor prognosis.

Methods

Retrospective study including 118 patients with HFS treated with BTX-A from 2019 January to 2023 April. Demographic and etiological variables as well as doses, number of sessions of BTX-A, infiltrated muscles, therapeutic response according to the Cohen evaluation scale, and side effects were analyzed. Logistic regression analysis was performed to identify the factors that are associated with the short-term prognosis of BTX-A for the treatment of HFS.

Results

Among the 118 patients with HFS included in this study, 57 achieved complete relief, 51 had significant relief, 7 had partial relief, and no improvement was observed in 3. The overall effective rate was 91.53 %. Results from the univariate analysis indicated that male, drinking, diabetes, and hypertension were all associated with poor short-term prognosis of BTX-A in the treatment of HFS. Multivariable logistic regression analysis further revealed that hypertension was an independent risk factor for poor short-term prognosis following BTX-A treatment for HFS (OR=5.847, P<0.05).

Conclusion

BTX-A was effective in treating HFS and had minimal adverse effects. Hypertension was an independent risk factor for poor short-term prognosis following BTX-A treatment of HFS.

Symptomatic Treatment of Extrapyramidal Hyperkinetic Movement Disorders

Extrapyramidal hyperkinetic movement disorders comprise a broad range of phenotypic phenomena, including chorea, dystonia, and tics. Treatment is generally challenging and individualized, given the overlapping phenomenology, limited evidence regarding efficacy, and concerns regarding the tolerability and safety of most treatments. Over the past decade, the treatment has become even more intricate due to advancements in the field of deep brain stimulation as well as optimized dopamine- depleting agents. Here, we review the current evidence for treatment modalities of extrapyramidal hyperkinetic movement disorders and provide a comprehensive and practical overview to aid the choice of therapy. Mechanism of action and practical intricacies of each treatment modality are discussed, focusing on dosing and adverse effect management. Finally, future therapeutic developments are also discussed.

TRPV1+ neurons alter Staphylococcus aureus skin infection outcomes by affecting macrophage polarization and neutrophil recruitment

BACKGROUND

The interaction between the nervous system and the immune system can affect the outcome of a bacterial infection. Staphylococcus aureus skin infection is a common infectious disease, and elucidating the relationship between the nervous system and immune system may help to improve treatment strategies.

RESULTS

In this study, we found that the local release of calcitonin gene-related peptide (CGRP) increased during S. aureus skin infection, and S. aureus could promote the release of CGRP from transient receptor potential cation channel subfamily V member 1 (TRPV1+) neurons in vitro. The existence of TRPV1+ neurons inhibited the recruitment of neutrophils to the infected region and regulated the polarization of macrophages toward M2 while inhibiting polarization toward M1. This reduces the level of inflammation in the infected area, which aggravates the local infection. Furthermore, this study demonstrates that TRPV1 may be a target for the treatment of S. aureus skin infections and that botulinum neurotoxin A (BoNT/A) and BIBN4096 may reverse the inhibited inflammatory effect of CGRP, making them potential therapeutics for the treatment of skin infection in S. aureus.

CONCLUSIONS

In S. aureus skin infection, TRPV1+ neurons inhibit neutrophil recruitment and regulate macrophage polarization by releasing CGRP. BoNT/A and BIBN4096 may be potential therapeutic agents for S. aureus skin infection.

Tailored Indications for Different Neurotoxins

Background

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

Methods

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

Results

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

Conclusions

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

Immunogenicity of DaxibotulinumtoxinA for Injection in Glabellar Lines

DaxibotulinumtoxinA-lanm for injection (DAXI), a novel botulinum toxin type A formulation, contains a purified 150-kD core neurotoxin (daxibotulinumtoxinA) and proprietary stabilizing peptide (RTP004), and is approved for glabellar line treatment. As with any biologic product, DAXI may potentially be immunogenic and elicit unwanted antibody formation, possibly resulting in partial or complete treatment failure. The immunogenicity of DAXI was assessed in 2 double-blind, placebo-controlled, single-dose studies and an open-label safety study of up to 3 repeat treatments. Of the 2737 evaluable patients, none developed neutralizing antibodies to daxibotulinumtoxinA and 0.8% developed treatment-related nonneutralizing anti-daxibotulinumtoxinA-binding antibodies. Of evaluable patients exposed to RTP004 with either DAXI or placebo, 1.3% developed treatment-related anti-RTP004-binding antibodies, which were mostly transient. No patient developed binding antibodies to both daxibotulinumtoxinA and RTP004. All patients with treatment-related binding antibodies to daxibotulinumtoxinA or RTP004 achieved a clinical response (none or mild glabellar line severity) at Week 4 following each DAXI treatment cycle. The duration of clinical response was not different between treatment cycles when antibodies were detected vs when they were absent. Although the analysis population was small compared to the number of patients likely to receive repeated treatment in clinical practice, these results suggest that DAXI administration at the approved glabellar lines dose has low immunogenic potential and that nonneutralizing antibodies to daxibotulinumtoxinA or RTP004 occur infrequently and often transiently, and have no impact on clinical efficacy, safety, or duration of action. Real-world data encompassing larger numbers of patients is needed to substantiate these results.

LEVEL OF EVIDENCE: 3

High Levels of Physical Activity Reduce the Esthetic Durability of Botulinum Toxin Type A: A Controlled Single-Blind Clinical Trial

The present study aimed to evaluate the influence of physical activity on the durability of the esthetic effect of botulinum toxin type A (BoNT-A). Sixty female patients were allocated to three groups (n = 20) according to their physical activity level (PA): Low PA, Moderate PA, and High PA. All groups received a single injection of onabotulinumtoxinA, considering standardized doses in the frontalis (12U), corrugator supercilia (7U, each), and procerus muscles (4U). Outcomes were measured using electromyography (EMG), Merz 5-point scales, and Face-Q scales (perceived age and lines between eyebrows). A follow-up occurred after 30, 60, and 90 days. EMG results showed a significant decrease in muscle activity in the Low-PA group at all follow-ups compared with the other groups (p < 0.001). The Merz scale scores showed that the severity of forehead and glabellar lines significantly improved in the Low-PA group throughout this study compared with the other groups (p < 0.001). No significant differences between groups were found in the Face-Q scale for perceived age, while the Face-Q scale for lines between eyebrows showed better results for Low-PA (p < 0.01) and Moderate-PA (p < 0.01) groups compared to the High-PA group at the 30- and 90-day follow-ups. The durability of the esthetic effect of BoNT-A seems to be negatively influenced by the level of physical activity.

Auxiliary rehabilitation training after calf contouring with botulinum toxin type A injection reduces adverse reactions and improves satisfaction

PURPOSE

To analyze the effect of adjuvant rehabilitation training after calf contouring with botulinum toxin type A (BTX-A) injection.

METHODS

Clinical data of 48 female beauty seekers who underwent calf contouring at the Plastic Surgery Laser Center of Guangdong Second People's Hospital from January 2021 to June 2022 were retrospectively analyzed. Among them, 24 cases received routine care from January 2021 to December 2021 and were included in a control group, and 24 cases received rehabilitation care with auxiliary rehabilitation training from January 2022 to June 2022 that were in an observation group. The subjects were followed up for 24 weeks to observe the curative effect, and the injection efficacy was compared between the two groups. The maximum calf circumference (MCC) and gastrocnemius muscle thickness (GMT) were comparatively analyzed before and 2, 4, 12, and 24 weeks after treatment. The incidence of adverse reactions and satisfaction rate were also compared.

RESULTS

Both groups showed reduced calf circumferences after injection, with soft and uniform calf curves. No inter-group statistical significance was identified in terms of curative effects. Reduced MCC and GMT were observed in both groups at 2, 4, 12, and 24 weeks after treatment, with lower values in the observation group than in the control group at week 2, 4, and 12. The observation group also showed markedly fewer adverse reactions and higher satisfaction rate than the control group.

CONCLUSIONS

BTX-A injection is effective in calf contouring and can significantly reduce the MCC and GMT. In addition, post-injection rehabilitation training can significantly reduce the occurrence of adverse reactions and improve patient satisfaction.

Therapeutic Applications of Botulinum Neurotoxins in Veterinary Medicine

Botulinum neurotoxins (BoNTs) are emerging as multipurpose therapeutic compounds for the treatment of several different syndromes involving peripheral and central nervous systems, and muscular and musculoskeletal disorders both in human and veterinary medicine. Therefore, the study of BoNTs is rapidly developing and identifying newly produced BoNT variants. Efforts should be made to clarify the biological and pharmacological characteristics of these novel BoNTs as well as the natural ones. The high potential of BoNTs as a therapeutic compound for medical syndromes lies in its ability to reach a specific cell type while bypassing other cells, thus having mild or no side effects. In this paper the recent developments in BoNTs are reviewed with the aim of analyzing the current knowledge on BoNTs' biological mechanisms of action, immunogenicity, formulations, and therapeutic applications in the veterinary field, highlighting advantages and drawbacks and identifying the gaps to be filled in order to address research priorities.

A technology evaluation of the atypical use of a CPP-containing peptide in the formulation and performance of a clinical botulinum toxin product

INTRODUCTION

Cell-penetrating peptides (CPPs), are small peptides that facilitate cytosolic access and, thus, transport of therapeutic macromolecules to intracellular sites when conjugated to cargo proteins. As with all new delivery platforms, clinical development of CPP-containing therapeutics has faced considerable challenges.

AREAS COVERED

RTP004 is a novel, 35-amino acid, bi-CPP-containing excipient that binds noncovalently with its cargo (botulinum toxin type A) rather than conjugated as a fusion protein. An RTP004-containing neurotoxin formulation, daxibotulinumtoxinA-lanm for injection (DAXI), has recently been approved by the FDA. The formulation and pharmacological characteristics of RTP004 and the efficacy and safety of the RTP004-neurotoxin formulation are discussed.

EXPERT OPINION

RTP004 is a highly positively charged lysine- and arginine-rich structure that provides formulation stability, preventing self-aggregation of the cargo protein and adsorption to container surfaces. The presence of RTP004 in the formulation also appears to increase presynaptic binding of the neurotoxin, reduces post-injection diffusion, and thus facilitates an increase in the cleavage of the intracellular substrate for the botulinum toxin, likely through enhanced cellular uptake. The RTP004-neurotoxin formulation is the first CPP-containing product approved for clinical use. The potential for RTP004 to facilitate other therapeutic cargo molecules requires further research.

Improving the Efficacy of Botulinum Toxin for Cervical Dystonia: A Scoping Review

Cervical dstonia (CD) is a chronic disorder with a significant detrimental impact on quality of life, requiring long-term treatment. Intramuscular injections of botulinum neurotoxin (BoNT) every 12 to 16 weeks have become the first-line option for CD. Despite the remarkable efficacy of BoNT as a treatment for CD, a significantly high proportion of patients report poor outcomes and discontinue the treatment. The reasons that drive sub-optimal response or treatment failure in a proportion of patients include but are not limited to inappropriate muscle targets and/or BoNT dosing, improper method of injections, subjective feeling of inefficacy, and the formation of neutralizing antibodies against the neurotoxin. The current review aims to complement published research focusing on the identification of the factors that might explain the failure of BoNT treatment in CD, highlighting possible solutions to improve its outcomes. Thus, the use of the new phenomenological classification of cervical dystonia known as COL-CAP might improve the identification of the muscle targets, but more sensitive information might come from the use of kinematic or scintigraphic techniques and the use of electromyographic or ultrasound guidance might ensure the accuracy of the injections. Suggestions are made for the development of a patient-centered model for the management of cervical dystonia and to emphasize that unmet needs in the field are to increase awareness about the non-motor spectrum of CD, which might influence the perception of the efficacy from BoNT injections, and the development of dedicated rehabilitation programs for CD that might enhance its effectiveness.

FDA Approvals of Biologics in 2022

The year 2022 witnessed the control of the COVID-19 pandemic in most countries through social and hygiene measures and also vaccination campaigns. It also saw a decrease in total approvals by the U.S. Food and Drug Administration (FDA). Nevertheless, there was no fall in the Biologics class, which was boosted through the authorization of 15 novel molecules, thus maintaining the figures achieved in previous years. Indeed, the decrease in approvals was only for the category of small molecules. Monoclonal antibodies (mAbs) continued to be the drug class with the most approvals, and cancer remained the most targeted disease, followed by autoimmune conditions, as in previous years. Interestingly, the FDA gave the green light to a remarkable number of bispecific Biologics (four), the highest number in recent years. Indeed, 2022 was another year without the approval of an antimicrobial Biologic, although important advancements were made in targeting new diseases, which are discussed herein. In this work, we only analyze the Biologics authorized in 2022. Furthermore, we also consider the orphan drugs authorized. We not only apply a quantitative analysis to this year's harvest, but also compare the efficacy of the Biologics with those authorized in previous years. On the basis of their chemical structure, the Biologics addressed fall into the following classes: monoclonal antibodies; antibody-drug conjugates; and proteins/enzymes.

Current Status of Peptide Medications and the Position of Active Therapeutic Peptides with Scorpion Venom Origin

: Peptides are highly potent, selective, and relatively safe therapeutics. Over the past two decades, natural peptides have been obtained, studied, and eventually approved by the Food and Drug Administration (FDA) due to advancements in identification, production, modification, and analytical technologies. Some peptide therapeutics has been derived from the venom gland of venomous animals, including snake, leech, lizard, snail, and scorpion. Scorpion was identified as a reservoir of important peptides with pharmaceutical properties. The scorpion uses these peptides for capturing prey and defense. However, their pharmacological properties in treating different diseases, including cardiac problems, autoimmune and infectious diseases, and diverse cancers, have been confirmed. Ion channel modifiers are the greatest components of the scorpion venom glands. Due to advances in proteomic and transcriptomic approaches, the identification of new scorpion venom peptides is steadily increasing. In this review, we tried to represent the current status of peptide medicines and describe the last peptide medications approved by FDA in 2022. Moreover, we will further explain potent peptides originating from scorpion venom, which have gone through important steps to be approved.

Cosmetic Treatment Using Botulinum Toxin in the Oral and Maxillofacial Area: A Narrative Review of Esthetic Techniques

Botulinum toxin (BoNT) is an anaerobic rod-shaped-neurotoxin produced by Clostridium botulinum, that has both therapeutic and lethal applications. BoNT injection is the most popular cosmetic procedure worldwide with various applications. Patients with dynamic wrinkles in areas such as the glabella, forehead, peri-orbital lines, nasal rhytides, and perioral rhytides are indicated. Excessive contraction of muscles or hyperactivity of specific muscles such as bulky masseters, cobble stone chins, gummy smiles, asymmetric smiles, and depressed mouth corners can achieve esthetic results by targeting the precise muscles. Patients with hypertrophic submandibular glands and parotid glands can also benefit esthetically. There are several FDA-approved BoNTs (obabotuli-numtoxinA, abobotulinumtoxinA, incobotulinumtoxinA, letibotulinumtoxinA, prabotulinumtox-inA, daxibotulinumtoxinA, rimbotulinumtoxinB) and novel BoNTs on the market. This paper is a narrative review of the consensus statements of expert practitioners and various literature on the injection points and techniques, highlighting both the Asian and Caucasian population separately. This paper can serve as a practical illustrative guide and reference for optimal, safe injection areas and effective doses for application of BoNT in the face and oral and maxillofacial area. The history of BoNT indications, contraindications, and complications, and the merits of ultrasonography (US)-assisted injections are also discussed.

DAXI (DaxibotulinumtoxinA) - An Innovative Approach for Frown Lines

Glabellar frown lines, also known as worry lines, are a common sign of aging. The current treatment option for glabellar lines is subjective and ranges from economical anti-wrinkle creams and skin resurfacing techniques such as microdermabrasion and fillers to highly expensive facelifts. Botox^® has been the mainstream treatment for decades, but the suggested time between treatments for most toxins is 12-16 weeks, and evidence shows that patients being treated for glabellar lines want longer-lasting results. Recently, on September 16th, the US Food and Drug Administration (FDA) approved the development of daxibotulinumtoxinA (DAXI) for injection based on clinical trials (SAKURA 1, 2, and 3). These encouraging findings followed by FDA approval mean that the need for repeated treatments to sustain the desired outcome has decreased. DAXI could be a reliable and secure choice for reducing the appearance of wrinkles on the face caused by muscle activity, and its long duration has the potential to enhance the treatment of both therapeutic and cosmetic disorders.

Treatment of Upper Facial Lines With DaxibotulinumtoxinA for Injection: Results From an Open-Label Phase 2 Study

BACKGROUND

Simultaneous treatment of moderate-to-severe upper facial lines is reflective of real-world clinical practice.

OBJECTIVE

To evaluate the efficacy and safety of daxibotulinumtoxinA-lanm for injection (DAXI) for simultaneous treatment of glabellar, forehead, and lateral canthal (LC) lines.

METHODS

In this open-label, single-arm Phase 2 study, patients (48 enrolled, 94% completed, follow-up 24-36 weeks) received DAXI 40U (glabellar), 32U (forehead), and 48U (LC) lines. Key efficacy endpoints: percentages of patients achieving none/mild wrinkle severity (investigator-rated) for each upper facial line scale at Week 4.

RESULTS

At Week 4, most patients achieved none/mild wrinkle severity (investigator-rated): glabellar (96%), forehead (96%), and LC (92%). Median times to loss of none/mild response (investigator- and patient-rated) among all patients were: 24.6 (glabellar), 20.9 (forehead), and 24.9 (LC) weeks; and 25.0, 24.0, and 28.1 weeks, respectively, among Week-4 responders. At Week 4, most patients reported improvements (Global Aesthetic Improvement Scale: 96%-98%) and high satisfaction rates (85%-98%). Five patients experienced treatment-related adverse events: injection-site erythema (3 patients/7 events), facial discomfort (2 patients/2 events), and headache (1 patient/1 event). No patients experienced eyebrow or eyelid ptosis.

CONCLUSION

Simultaneous treatment of upper facial lines with DAXI was well tolerated and demonstrated high response rates, extended duration, and high patient satisfaction.

CLINICAL TRIAL REGISTRY

https://clinicaltrials.gov/ct2/show/NCT04259086.

Pathogenesis, diagnosis and therapy of facial synkinesis: A systematic review and clinical practice recommendations by the international head and neck scientific group

Introduction

Post-paralytic facial synkinesis after facial nerve injury produces functional disabilities and mimetic deficits, but also cosmetic and non-motor psychosocial impairments for the patients. These patients typically have a high and continuous high motivation for rehabilitation. The aim is to inform the affected patients and their therapeutic professionals (otorhinolaryngologist - head and neck surgeons; oral-maxillofacial surgeons, plastic and reconstructive surgeons, neurosurgeons, neurologists, and mime therapists be it speech and language therapy- or physiotherapy-based) and to provide practical recommendations for diagnostics and a stepwise systematic treatment approach of facial synkinesis.

Methods

In the first phase, a systematic literature search on the topic in PubMed and ScienceDirect starting in 2008 resulted in 132 articles. These were the basis for the review and a comprehensive series of consensus statements on the most important diagnostic tests and treatment options. In the second phase, one consensus article circulated among the membership of the International Head and Neck Scientific Group until a final agreement was reached for all recommendations.

Results

Diagnostics should include a standardized assessment of the degree of synkinesis using validated clinician-graded instruments and synkinesis-specific patient-reported outcome measures. Treatments for facial synkinesis include facial training mainly based on facial biofeedback retraining, chemodenervation with botulinum toxin, selective neurectomy, myectomy, and any combination treatment of these options.

Conclusion

A basic understanding of the pathomechanisms of synkinesis is essential to understand the treatment strategies. A standardized assessment of the synkinetic symptoms and the individual synkinesis pattern is needed. The first-line treatment is facial training, followed by botulinum toxin. Surgery is reserved for individual cases with unsatisfactory first-line treatment.

The Dystonias

PURPOSE OF REVIEW

This article discusses the most recent findings regarding the diagnosis, classification, and management of genetic and idiopathic dystonia.

RECENT FINDINGS

A new approach to classifying dystonia has been created with the aim to increase the recognition and diagnosis of dystonia. Molecular biology and genetic studies have identified several genes and biological pathways involved in dystonia.

SUMMARY

Dystonia is a common movement disorder involving abnormal, often twisting, postures and is a challenging condition to diagnose. The pathophysiology of dystonia involves abnormalities in brain motor networks in the context of genetic factors. Dystonia has genetic, idiopathic, and acquired forms, with a wide phenotypic spectrum, and is a common feature in complex neurologic disorders. Dystonia can be isolated or combined with another movement disorder and may be focal, segmental, multifocal, or generalized in distribution, with some forms only occurring during the performance of specific tasks (task-specific dystonia). Dystonia is classified by clinical characteristics and presumed etiology. The management of dystonia involves accurate diagnosis, followed by treatment with botulinum toxin injections, oral medications, and surgical therapies (mainly deep brain stimulation), as well as pathogenesis-directed treatments, including the prospect of disease-modifying or gene therapies.

Lifting the Mouth Corner: A Systematic Review of Techniques, Clinical Outcomes, and Patient Satisfaction

BACKGROUND

Mouth corners are an essential part of the centrofacial area for perception of attractiveness and emotions. Downturned mouth corners are a result of aging or have a congenital origin. Different mouth corner lifting techniques are described in the literature.

OBJECTIVES

This review was performed to systematically assess and compare invasive and noninvasive mouth corner lifting techniques and their effectiveness, patient satisfaction, and adverse effects.

METHODS

MEDLINE (via PubMed), EMBASE (OvidSP), and the Cochrane Central Register of controlled trials databases were searched for clinical and observational studies published in peer-reviewed academic journals with abstracts available (searched from May 18, 2019, to December 18, 2021). Outcomes of interest were aesthetic mouth corner lifting techniques, the degree of lift as well as the longevity of the lifting effect, patient satisfaction, and adverse effects. Techniques were subdivided in invasive techniques and noninvasive techniques.

RESULTS

Out of 968 studies found from the search, 11 were included in the qualitative analysis. In general, surgical techniques seem to have a better mouth corner lifting effect than nonsurgical techniques; however, objective evidence is weak, and surgery inevitably results in a scar. Reported patient satisfaction was good for both surgical and nonsurgical techniques and no severe complications have been described.

CONCLUSIONS

Surgical techniques seem to have a better lifting effect on mouth corners than nonsurgical techniques. Nevertheless, objective evidence is weak, and a scar is inevitable.

LEVEL OF EVIDENCE: 4