A randomized, blinded, controlled USA field study to assess the use of fluralaner tablets in controlling canine flea infestations

Abstract

BackgroundThe novel isoxazoline molecule fluralaner provides 12 weeks activity against fleas and 8 to 12 weeks against tick infestations according to label claims.MethodsThis blinded, multi-center study in client-owned dogs evaluated the flea control provided by a single oral fluralaner treatment (25–56 mg/kg; Bravecto™, Merck Animal Health) compared to a control group administered three oral spinosad (30 – 60 mg/kg; Comfortis®, Elanco) treatments at 4-week intervals together with an amitraz collar (9%, Preventic®, Virbac). Households were randomized (3:1 ratio) to either fluralaner (224 dogs, 118 households) or control (70 dogs, 39 households). Within households, one primary dog with at least 10 live fleas at enrollment was randomly selected for whole body flea counts every 4 weeks through Week 12; all dogs were followed for safety until Week 12. Fluralaner dogs received two additional doses at Weeks 12 and 24 for further safety and palatability observations through Week 26.ResultsGeometric mean flea count reductions from baseline for the fluralaner group at Weeks 4, 8, and 12 were 99.7%, 99.8%, and 99.8%, respectively; and 96.1%, 99.5%, and 99.6% for the spinosad controls. Percentages of flea-free primary dogs at Weeks 4, 8, and 12 were 91.1%, 95.4%, and 95.3% for the fluralaner group; and 44.7%, 88.2%, and 84.4% for the controls; the differences were significant at Weeks 4 (P < 0.0001) and 12 (P = 0.0370). Improvements in veterinarian assessed flea allergy dermatitis (FAD) were observed in both groups. Fluralaner tablets were accepted free choice in over 90% of doses. The most common adverse event was vomiting, occurring in 7.1% of the fluralaner group and 14.3% of the controls. No treatment related serious adverse events were reported.ConclusionsA single treatment of dogs with the palatable fluralaner flavored chewable tablet provides a safe and effective option for 12 weeks of flea control at least equivalent to that of 3 sequential treatments with spinosad tablets. Linked to the high level of flea control was a substantial alleviation of associated signs of FAD.

A randomized, blinded, controlled USA field study to assess the use of fluralaner topical solution in controlling canine flea infestations

“…As would be expected from the use of highly effective flea control measures, and matching findings in earlier field studies, treatment with topical fluralaner was followed by resolution of FAD signs in treated dogs [3, 4, 11]. …”

“…This efficacy was greater than the flea control efficacy of the fipronil-methoprene treatment at several time points. Results of this field study seen with the topical fluralaner formulation align with results of a study with a similar design that assessed the chewable fluralaner formulation [3]. In both studies, a single treatment/application resulted in a > 99% reduction in live flea counts within 4 weeks, and sustained flea count reductions of > 99% through 12 weeks; more than 80% of fluralaner-treated dogs were free of fleas at 4 weeks, and more than 90% were free of fleas at the 8- and 12-week assessments.…”

“…Furthermore, the results observed are also consistent with findings in other field studies. For instance, in the aforementioned field trial with the oral fluralaner formulation, the oral fluralaner group had > 90% of dogs flea-free after a single treatment [3]. In an earlier spinosad study in which fipronil-methoprene was a comparator product, only 38% of dogs in the fipronil-methoprene group were free of fleas after three consecutive monthly treatments [9], aligning with our results of 30% of flea-free dogs receiving three owner-applied fipronil-methoprene treatments at 4 week intervals.…”

“…A separate laboratory study found that 100% efficacy against fleas was maintained for 122 days post-treatment, with a corresponding elimination of flea egg laying [2]. The prolonged efficacy of oral fluralaner treatment demonstrated in laboratory studies translated into similar benefits under field conditions: a single oral fluralaner treatment of naturally infested dogs provided a significant increase in the percentage of flea-free client-owned dogs compared with three treatments at 28 day intervals with orally administered spinosad [3]. In another study, a single fluralaner treatment resolved flea allergy dermatitis (FAD) signs and reduced owner-assessed scores of their dogs’ pruritus [4].…”

Results from a U.S. Dog Owner Survey on the Treatment Satisfaction and Preference for Fluralaner against Flea and Tick Infestations

“…The fluralaner re-treatment interval is three times longer than the re-treatment interval for other flea/tick products that are dosed every 4 weeks. Fluralaner offers a new approach to canine F/T control, based on rapid and persistent acaricidal and insecticidal activity [6][7][8].…”