A randomized,controlled study to assess the efficacy and safety of lotilaner (Credelio™) in controlling ticks in client-owned dogs in Europe

Background: oral administration of lotilaner flavoured chewable tablets (credelio™,elanco) to dogs has been shown to provide a rapid onset of killing activity of infesting ticks,with sustained efficacy for at least 35 days. a study was undertaken in europe to confirm lotilaner's safety and anti-tick efficacy in client-owned dogs. methods: in this assessor-blinded study,dogs were enrolled at 19 clinics in germany,hungary and portugal. qualifying households with no more than three dogs were randomized in an approximate 2:1 ratio to a lotilaner or fipronil/(s)-methoprene (fsm) (frontline® combo spot-on,merial) treatment group. one household dog with at least three live attached ticks was the primary dog. treatments were dispensed days 0,28 (± 2) and 56 (± 2) for owner administration to all household dogs. tick counts were performed on primary dogs days 7 (± 1),and ±2 days on days 14,21,28,42,56,70 and 84; supplementary dogs were assessed for safety ± 2 days on days 28,56 and 84. efficacy was assessed by comparing mean day 0 live attached tick counts with subsequent counts. results: the most frequently retrieved ticks were ixodes ricinus,dermacentor reticulatus and rhipicephalus sanguineus (sensu lato),with ixodes hexagonus also present. in the lotilaner group (n = 127) geometric mean tick count reductions were at least 98% from the first post-treatment visit (day 7) through day 56,when efficacy was 100%. for fsm (n = 68),efficacy remained at least 96% through day 84,but at no point were all dogs free of live attached ticks. mean counts in lotilaner-treated dogs were significantly lower than fsm-treated dogs on days 7,42,70 and 84 (p < 0.05). percent efficacy over all post-enrolment visits was 99.3 and 98.3% for lotilaner and fsm groups,respectively (t (190) = 2.23,p = 0.0268). owners successfully administered all treatments,and both products were well-tolerated. conclusion: under european field conditions,lotilaner flavoured chewable tablets administered monthly,were > 98% effective in eliminating live ticks from the first post-treatment assessment (day 7) through day 56 and maintained 100% of dogs tick-free on days 70 and 84. lotilaner was safe,providing superior tick control to fsm administered according to the same schedule. © 2017 the author(s).