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

摘要

Background The novel isoxazoline molecule fluralaner provides 12 weeks activity against fleas and 8 to 12 weeks against tick infestations according to label claims. Methods This 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. Results Geometric 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?