A European field assessment of the efficacy of fluralaner (Bravecto®) chewable and spot-on formulations for treatment of dogs with generalized demodicosis

A systematic review of fluralaner as a treatment for ectoparasitic infections in mammalian species

Fluralaner (Bravecto™) is a novel isoxazoline ectoparasiticide used for controlling ectoparasites of domestic mammals and is increasingly being used on wildlife. The aim of this systematic review was to evaluate the efficacy, pharmacokinetics, and safety of fluralaner on mammals given its increasing use. The search was performed in GoogleScholar and the SciFinder databases using the terms 'fluralaner' and 'Bravecto™', and was concluded on 30th August, 2024. A total of 250 references were initially saved and reduced to 121 peer-reviewed journal articles using PRISMA guidelines, based on the removal of duplicates, those published in low quality journals (ranked less than Q2), and limiting publications to clinical trials. Articles were then categorised and ranked using the level of evidence, Cochrane 'risk of bias' assessment tool, methodological quality, and study size. Overall, the efficacy of fluralaner has been assessed on 14 mammalian species, and pharmacokinetic investigations conducted on 15. Fluralaner was mostly effective at treating some ectoparasites on captive individuals when there was little chance of re-infection; however, it did not prevent bites from blood-sucking ectoparasites and could not prevent blood-borne pathogen transfer to host animals. Very few studies have investigated the pharmacokinetics of fluralaner, and hence were difficult to compare; however, wombats differed greatly from their eutherian counterparts in their Cmax and t½ values and require further investigation. Overall, fluralaner was deemed moderately safe; however, most studies were classified as fair in terms of quality and most studies were based on small or very small sample numbers. Nineteen studies reported side effects, one of which included signs of severe neurological toxicity, with most of the articles not reporting on safety either positively or negatively. Concerns were raised regarding the extended time fluralaner was detected in faeces and subsequently environmental contamination is a concern. No longer-term impacts of the use of fluralaner have been investigated, and wider implications of the use of this ectoparasiticide have not yet been assessed.

A New Herbal Medicine Formulation with Potential Anti-scabies Properties to Treat Demodex and Sarcoptes Parasites

Scabies is considered an external parasite notorious for its high prevalence causing severe and contagious skin lesions in humans and animals worldwide. This study has introduced a medicine to treat dogs infested with scabies (variants of Demodex, Sarcoptes, Psoroptes, Otodectes, etc.). The present study offers a no-side-effect herbal formulation to treat dogs infested with scabies. Unlike oral and injectable medicines, which take the form of an ointment and are topically applied on-site, this medicinal formulation can be easily used without concerns over its side effects or consumption dosages. This medicinal formulation requires no skin rinsing due to its herbal and high skin absorption properties, as recovery may take less than a month with a maximum of two times of application. To carry out the experiment, 25 sick dogs with various breeds and ages suspected of scabies were gathered. Following accurate morphological examinations of all the samples, a deep skin chip of the lesion site was provided, which was examined by a microscope. Then, 13 dogs (Mix, Terrier, Pug, Husky, Spitz) were infested with Demodex scabies and 12 dogs (Pittbull, Mix, Shih Tzu, Terrier, Boxer, Setter) with Sarcoptic scabies. The prepared product was topically administered at a constant 2% dosage to the bodies of all the samples. To prepare the ointment, 1 g of Borax (Na2B4O7·10H2O) was first dissolved in 35 g deionized water and heated to 70°C. Then, 45 g of liquid paraffin (CnH2n+2) was mixed with 1 g of Carvacrol (C10H14O) and 1 g of geranium (C10H18O) and stirred well to become a phase. Later, 17 g of the melted beeswax (C15H31COOC30H61) was added to the liquid paraffin compound. In the end, the aqueous phase was added to the oil phase, and the mixture process immediately began in one direction with a glass stirrer and continued until the product cooled down. Essential oils (EO) was obtained by steam distillation of fresh Thyme and Rose-Acented Geranium in a stainless steel distillation apparatus (alembic) for 3 h. The main components of the essential oils used in the formulation were performed using a Hewlett-Packard GC system interfaced with a mass spectrometer equipped with an HP5-MS capillary column (30 m, 0.32 mm, 0.25 µm film thicknesses). For GC-MS detection, electron ionization with ionization energy of 70 eV was used. To examine the presence of scabies, weekly skin sampling was performed, and the treatment continued until 30 days, when no skin chip of the scabies was noted. The findings revealed that the formulation developed no side effects and removed the daily use, as it could be administered once or twice a week. Also, complete recovery of scabies in all the breeds was found to be less than a month at most. This medicinal formulationcan be easily used without concerns over its side effects or consumption dosages. This study introduced a herbal formulation with effective herbal ingredients without any side effects to treat the sarcoptes and demodex parasites; unlike other chemical compounds, this medicinal formulation has no side effects, while some other formulations could develop side effects.

Fluralaner 5.46% (w/w) flavored chewable tablet (Bravecto® 1-Month) is effective for treatment of canine generalized demodicosis

Background

Orally administered fluralaner (13.64% w/w) is effective for treating canine generalized demodicosis. A study was initiated to assess the efficacy of a novel 5.46% w/w fluralaner chewable tablet formulation for monthly administration in the treatment of this disease.

Methods

Client-owned dogs diagnosed with generalized demodicosis were acclimatized to laboratory conditions and randomized to receive either orally administered fluralaner (Bravecto^® 1-Month) (10.0 to 14.4 mg/kg body weight) (n = 8) or topical imidacloprid-moxidectin (Advocate^® for dogs, Elanco) applied per label on days 0, 28, and 56 (n = 8), or more frequently for ongoing severe demodicosis. On days −2, 28, 56, and 84, deep skin scrapings were taken from five sites on each dog for mite identification and counting, and semiquantitative clinical assessments of generalized demodicosis were recorded. Primary efficacy was based upon arithmetic mean mite count reductions relative to pre-treatment.

Results

By day 28, mean pre-treatment mite counts, > 600 in both groups, were significantly reduced by 99.7% and 89.5% (both P < 0.001) in the fluralaner and imidacloprid-moxidectin groups, respectively. Parasitological cure (100% reduction in mite counts on days 56 and 84) was achieved in all fluralaner-treated dogs (100%) and in two imidacloprid-moxidectin-treated dogs (25%). In the imidacloprid-moxidectin group, the reduction in mean mite counts was 89.5% (day 28), 94.4% (day 56), and 97.5% (day 84). All study dogs were free of crusts on days 56 and 84. Scales resolved by day 84 in all fluralaner-treated dogs and in three imidacloprid-moxidectin-treated dogs. All fluralaner-treated dogs and five imidacloprid-moxidectin-treated dogs had > 90% hair regrowth on day 84.

Conclusion

Three consecutive monthly orally administered treatments with fluralaner (5.46% w/w) flavored chewable tablets (minimum dose rate 10 mg/kg body weight) eliminated Demodex canis mites from dogs diagnosed with generalized demodicosis.

Graphical Abstract

Evaluation of a clinical scoring system for canine demodicosis

BACKGROUND

Canine demodicosis is a common disease in small animal practice. Although a number of studies evaluating treatment efficacy for canine demodicosis have used clinical scoring systems, none have been validated.

OBJECTIVES

This study evaluated the validity, reliability, reproducibility and sensitivity to change of a clinical scoring system for canine demodicosis.

METHODS AND MATERIALS

Fifty-eight dogs with generalised demodicosis were evaluated using a clinical scoring system that assessed erythema, comedones/ papules/pustules, follicular casts/scales/crusts and alopecia, rated from none to mild, moderate and severe in 36 body locations. Two evaluators scored lesions at monthly consecutive visits during treatment. Mites were counted to a maximum of 50 in four deep skin scrapings. With >50 mites, the approximate mite number was calculated with the help of a grid drawn onto the slide before placing the scraped material onto it.

RESULTS

A Pearson correlation coefficient showed a high interobserver reliability (r = 0.97) between two different clinicians evaluating the same dog. The Wilcoxon signed rank test showed good sensitivity to change with a reduction of clinical scores with each of the first six evaluations (P < 0.0001). A linear mixed model also showed a clear reduction in mite counts (P < 0.001) and clinical scores (P < 0.0001) from the first evaluation with time.

CONCLUSION AND CLINICAL RELEVANCE

The clinical scoring system for canine demodicosis evaluated in this study showed a good sensitivity to change and interobserver reliability, and can be used in studies evaluating canine demodicosis.

Long-term follow-up of a single dose of fluralaner in nine dogs with demodicosis

BACKGROUND

Long-term follow-up of oral fluralaner for canine demodicosis has not been demonstrated.

OBJECTIVES

A multicentre prospective open trial for the efficacy of oral fluralaner for the long-term (>12 month) management of canine demodicosis.

ANIMALS

Client-owned dogs diagnosed with demodicosis at nine veterinary clinics.

METHODS AND MATERIALS

A single fluralaner dose was administered orally. Although shampoo was allowed to treat secondary pyoderma, no other medication or shampoo was allowed, except for medication for possible underlying disorders. Each dog underwent a thorough parasitological and dermatological assessment monthly for three months and was followed up for >12 months.

RESULTS

Twenty-six dogs were enrolled. Their ages ranged from three months to 16 years. The cases were nine juvenile and 17 adult onsets; and 18 generalised and eight localised forms. Fluralaner administration resulted in 100% eradication of mites and complete resolution of all skin lesions at three months. Seventeen dogs were excluded from the one year follow-up evaluation as they had required a second dose of isoxazoline or died from causes unrelated to the fluralaner treatment. In the remaining nine cases, no relapse was observed in any of the dogs (six adult and three juvenile onsets; six generalised and three localised forms). Four dogs were monitored for over one year, one dog for over two years, and four dogs for three years.

CONCLUSIONS AND CLINICAL RELEVANCE

The results indicated that a single dose of fluralaner could effectively deliver a long-term cure when combined with managing underling conditions.

Human and Veterinary Vaccines for Lyme Disease

Lyme disease (LD) is an emerging zoonotic infection that is increasing in incidence in North America, Europe, and Asia. With the development of safe and efficacious vaccines, LD can potentially be prevented. Vaccination offers a cost-effective and safe approach for decreasing the risk of infection. While LD vaccines have been widely used in veterinary medicine, they are not available as a preventive tool for humans. Central to the development of effective vaccines is an understanding of the enzootic cycle of LD, differential gene expression of Borrelia burgdorferi in response to environmental variables, and the genetic and antigenic diversity of the unique bacteria that cause this debilitating disease. Here we review these areas as they pertain to past and present efforts to develop human, veterinary, and reservoir targeting LD vaccines. In addition, we offer a brief overview of additional preventative measures that should employed in conjunction with vaccination.

Efficacy of orally and topically administered fluralaner (Bravecto®) for treatment of client-owned dogs with sarcoptic mange under field conditions

Background

Successful canine sarcoptic mange treatment requires immediate efficacy to eliminate active mites, and sustained activity to prevent re-infestation from in-contact animals and fomites. With extended acaricidal activity, fluralaner has been shown to be effective for treating this disease. To confirm this potential under field conditions, two fluralaner formulations were administered to mite-infested, client-owned dogs.

Methods

Households qualified for inclusion if they had at least one dog positive for Sarcoptes scabiei mites, confirmed by skin scraping, and at least one dog with clinical signs evocative of sarcoptic mange. Households were allocated to groups of dogs to receive a single treatment with either oral (Bravecto^® chewable tablets, MSD Animal Health) or topical (Bravecto^® Spot-on, MSD Animal Health), fluralaner at a dose of ≥ 25 mg/kg (range 25–56 mg/kg) on Day 0, or two treatments with oral sarolaner (Simparica^® tablets, Zoetis) (Days 0 and 28) at ≥ 2 mg/kg (2–4 mg/kg). All dogs in each household were treated with the same product. On the enrolment day and subsequently on Days 28, 56 and 84, deep skin scrapings were taken from at least five different body areas judged to be most likely to have active mite infestation. At each visit, the dog’s mange-associated skin lesions were recorded, and pruritus level was assessed.

Results

There were 98 participating households and 135 dogs enrolled across Albania, France, Italy and Portugal. On Day 28, more than 90% of dogs in each group were negative for mites. On Days 56 and 84, all study dogs were free of mites and most dermatological signs of sarcoptic mange had resolved. There were no treatment-related adverse events in any group.

Conclusions

A single treatment of client-owned, sarcoptic mange-affected dogs with either fluralaner chewable tablets or fluralaner spot-on formulation proved a safe and effective treatment of infestations with S. scabiei var. canis, maintained through 84 days (12 weeks) after treatment.