Clinical studies evaluating abametapir lotion, 0.74%, for the treatment of head louse infestation

Greater mechanistic understanding of the cutaneous pathogenesis of Stevens-Johnson syndrome/toxic epidermal necrolysis can shed light on novel therapeutic strategies: a comprehensive review

PURPOSE OF REVIEW

Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) are severe cutaneous adverse drug reactions (SCARs) characterized by widespread epithelial detachment and blistering, which affects the skin and mucocutaneous membranes. To date, therapeutic interventions for SJS/TEN have focused on systematic suppression of the inflammatory response using high-dose corticosteroids or intravenous immunoglobulin G (IgG), for example. No targeted therapies for SJS/TEN currently exist.

RECENT FINDINGS

Though our understanding of the pathogenesis of SJS/TEN has advanced from both an immunological and dermatological perspective, this knowledge is yet to translate into the development of new targeted therapies.

SUMMARY

Greater mechanistic insight into SJS/TEN would potentially unlock new opportunities for identifying or repurposing targeted therapies to limit or even prevent epidermal injury and blistering.

Investigating the Antibacterial Properties of Prospective Scabicides

Scabies is a dermatological disease found worldwide. Mainly in tropical regions, it is also the cause of significant morbidity and mortality due to its association with potentially severe secondary bacterial infections. Current treatment strategies for scabies do not consider the role of opportunistic bacteria, and here we investigate whether current and emerging scabicides can offer any anti-bacterial protection. Using the broth microdilution method, we examined antimicrobial potential of the current scabicide ivermectin and emerging scabies treatments: abametapir, mānuka oil, and its individual β-triketones. Our results demonstrate that the two novel scabicides abametapir and mānuka oil have antimicrobial properties against common scabies-associated bacteria, specifically Staphylococcus aureus, Streptococcus pyogenes, Streptococcus dysgalactiae subsp. equisimilis and Acinetobacter baumannii. The current scabicide ivermectin offers some antimicrobial activity and is capable of inhibiting the growth aforementioned bacteria. This research is important as it could help to inform future best treatment options of scabies, and scabies-related impetigo.

Head Lice

Head lice infestation is associated with limited morbidity but causes a high level of anxiety among caregivers of school-aged children and adolescents. Since the 2015 clinical report on head lice was published by the American Academy of Pediatrics, new medications have been approved, and an algorithm for management of affected patients is included. This revised clinical report clarifies current diagnosis and treatment protocols.

Synthetic Approaches to the New Drugs Approved During 2020

New drugs introduced to the market are privileged structures that have affinities for biological targets implicated in human diseases and conditions. These new chemical entities (NCEs), particularly small molecules and antibody-drug conjugates (ADCs), provide insight into molecular recognition and simultaneously function as leads for the design of future medicines. This Review is part of a continuing series presenting the most likely process-scale synthetic approaches to 44 new chemical entities approved for the first time anywhere in the world during 2020.

New chemistries for the control of human head lice, Pediculus humanus capitis: A mini-review

Pediculus lice represent one of the longest and most prevalent parasitic infestations of humans. Head lice are an economic and social concern whereas body lice pose a more serious public health threat. Significant progress has been made in the study of human lice over the last 10 years, allowing for new approaches in their control. An in vitro rearing system has made it possible to maintain insecticide-susceptible and -resistant reference strains, which allowed an in depth study of pediculicide resistance, including its underlying molecular mechanisms and the detection and monitoring of resistance. The generation of inbreed strains facilitated the efficient sequencing, assembly and annotation of the genomes and transcriptomes of both lice. The use of functional genomics and reverse genetics elucidated the genetics involved in the evolution of resistance and the discovery of novel target sites for the development of new pediculicides. In this review, four new effective pediculicide products, each with different mode of action and unique chemistries, will be presented. They have been found to be safe and selective, and control resistant lice. As such, they meet the criteria necessary to be used in rotations as a sustainable resistance management strategy.

Common pediatric infestations: update on diagnosis and treatment of scabies, head lice, and bed bugs

PURPOSE OF THE REVIEW

This review will update pediatric providers on the recent data regarding the epidemiology, diagnosis, and treatment of common skin infestations affecting children and adolescents.

RECENT FINDINGS

Standard superficial skin biopsy for scabies and the vacuum method for head lice can increase diagnostic accuracy and efficiency. There is growing resistance to some of the traditional treatments for scabies and head lice, and progress has been made in finding newer and potentially more effective treatments, such as oral moxidectin for scabies and abametapir for head lice. Recent studies have established the safety of traditional treatments, such as permethrin and oral ivermectin in infants and small children.

SUMMARY

Permethrin and ivermectin are both considered safe and effective for children and adolescents with scabies. Permethrin is generally considered safe in infants less than two months of age. Proper application of permethrin is critical, and providers should emphasize proper application technique. Treatment of head lice should only be initiated with active infestations. Resistance to permethrin continues to increase and other options are now available, including an over-the-counter topical ivermectin formulation. Identification and eradication of bed bug infestations are crucial in preventing bedbug bites.

Abametapir for the Treatment of Head Lice: A Drug Review

OBJECTIVE

This article reviews the pharmacology, safety, efficacy, and clinical importance of abametapir 0.74% (Xeglyze) for the treatment of head lice.

DATA SOURCES

From 2020 to May 2021, a systematic review of the MEDLINE and EMBASE databases was conducted using the terms abametapir, Xeglyze, Ha44, and head lice. Bibliographies, Food and Drug Administration (FDA) drug package inserts, and ClinicalTrials.gov were searched for further information.

STUDY SELECTION AND DATA EXTRACTION

All relevant full-text articles in English were considered for inclusion, with a final article date range of 1999 to 2020.

DATA SYNTHESIS

Abametapir chelates heavy metal cations and inhibits metalloproteinases critical to louse ova development, hatching, and adult survival. In phase II, abametapir had direct ovicidal activity inhibiting 100% of treated louse eggs from hatching, compared with 64% in the vehicle-treated group. In two identical phase III clinical trials, subjects treated with a single 10-minute application of abametapir had greater treatment success compared with vehicle-treated subjects, with 81.1% success versus 50.9% in study 1 (P = 0.001) and 81.8% versus 47.2% in study 2 (P < 0.001). Abametapir was well tolerated, with only mild adverse effects.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Abametapir is a newly FDA-approved, single-application treatment for head lice in patients aged 6 months and older. This review highlights the safety and efficacy of abametapir in the treatment of head lice.

CONCLUSIONS

In the wake of increasing widespread resistance to first-line treatment options, abametapir offers a safe and effective new treatment option for head lice infestations.

A year in pharmacology: new drugs approved by the US Food and Drug Administration in 2020

While the COVID-19 pandemic also affected the work of regulatory authorities, the US Food and Drug Administration approved a total of 53 new drugs in 2020, one of the highest numbers in the past decades. Most newly approved drugs related to oncology (34%) and neurology (15%). We discuss these new drugs by level of innovation they provide, i.e., first to treat a condition, first using a novel mechanisms of action, and "others." Six drugs were first in indication, 15 first using a novel mechanism of action, and 32 other. This includes many drugs for the treatment of orphan indications and some for the treatment of tropical diseases previously neglected for commercial reasons. Small molecules continue to dominate new drug approvals, followed by antibodies. Of note, newly approved drugs also included small-interfering RNAs and antisense oligonucleotides. These data show that the trend for declines in drug discovery and development has clearly been broken.

New drug approvals for 2020: Synthesis and clinical applications

53 New drugs including 38 chemical entities and 15 biologics were approved by the U.S. Food and Drug Administration during 2020. Among the marketed drugs, 34 new small molecule drugs and 4 new diagnostic agents with privileged structures and novel clinical applications represent as promising leads for the development of new drugs with the similar indications and improved therapeutic efficacy. This review is mainly focused on the clinical applications and synthetic methods of 34 small-molecule drugs newly approved by the FDA in 2020.

Effect of a New Head Lice Treatment, Abametapir Lotion, 0.74%, on Louse Eggs: A Randomized, Double-Blind Study

Few head lice treatments have demonstrated effectiveness against louse eggs. Abametapir, a metalloproteinase inhibitor, is able to target metalloproteinases critical to egg hatching and louse development. In this double-blind, phase 2 study, 50 subjects aged ≥3 years with active head lice infestation were randomized to receive a single treatment of abametapir lotion, 0.74%, or vehicle (control), applied to scalp and hair for 10 minutes. Ovicidal efficacy was measured by recording the hatch rate of eggs collected from each subject’s hair before and after treatment and incubated for 14 days. With abametapir, 100% of treated eggs remained unhatched compared with 64.0% for vehicle. Accounting for pretreatment hatch rates, the absolute reduction in egg hatching was 92.9% for abametapir versus 42.3% for vehicle (P < .0001). The most frequently reported adverse event was rash (16%). Abametapir lotion, 0.74%, demonstrated significant ovicidal activity against head lice eggs with a single application.

Clinical studies evaluating abametapir lotion, 0.74%, for the treatment of head louse infestation

BACKGROUND

There is a need for better control of head louse infestations. Abametapir is an inhibitor of metalloproteinases critical for louse survival and egg development. The efficacy of abametapir lotion, 0.74%, was assessed for its ability to clear head louse infestations after a single application.

METHODS

Two randomized, double-blind, multicenter, vehicle-controlled studies were conducted in subjects aged 6 months and older to compare the effectiveness of abametapir lotion versus vehicle control for eliminating head louse infestations without nit combing. Abametapir lotion was applied to dry hair for 10 minutes on day 0 and then rinsed with water. The primary endpoint was the proportion of index subjects (youngest household member with ≥ 3 live lice at screening) in the intent-to-treat population who were louse free at all follow-up visits through day 14. Older household members with one or more live lice at screening were designated as nonindex subjects and treated as per the index subject within their household.

RESULTS

In the intent-to-treat population (index subjects, N = 216), 81.5% of subjects treated with abametapir lotion were louse free through day 14 after a single treatment, versus 49.1% with vehicle (P < 0.001). For the combined index and nonindex population (N = 704), 85.9% were louse free through day 14 in the abametapir group, versus 61.3% in the vehicle group (P < 0.001). The most frequently reported adverse events were erythema (4.0%), rash (3.2%), and skin burning sensation (2.6%).

CONCLUSION

Abametapir lotion, 0.74%, was effective at clearing active head louse infestations through day 14 in subjects aged 6 months and older. All adverse events (including one serious but unrelated to study drug) resolved uneventfully.