Comparative Efficacy of Fipronil/(S)-Methoprene/Pyriproxyfen (FRONTLINE® Gold) and Sarolaner (SIM-PARICA®) Against Ctenocephalides felis flea Infestations on Dogs

A study was performed to compare the 6-hour efficacy of FRONTLINE (R) Gold (fipronil/(S)-methoprene/pyriproxyfen) with that of SIMPARICA (R) (sarolaner) against Ctenocephalides felis flea infestations on dogs. Twenty-four dogs were allocated to one of three groups, eight dogs in each group. On Day 0, each dog in Group B was treated with a dose of commercially available FRONTLINE Gold for dogs appropriate for its weight, and each dog in Group C was treated with a dose of commercially available SIMPARICA appropriate for its weight. Group A dogs remained untreated throughout the duration of the study. On each of Days 1, 7, 14, 21, and 28, all dogs were infested with 100 live, unfed Ctenocephalides felis fleas, and 6 hours later, all fleas were removed and counted. Using arithmetic means for all calculations, dogs treated with FRONTLINE Gold had significantly (p<0.01) fewer live fleas than the controls at 6 hours post-infestation on all assessment days from Day 1 to Day 28. FRONTLINE Gold's 6-hour efficacies were 88.8%, 98.2%, 99.2%, 95.2%, and 83.0% on Days 1, 7, 14, 21, and 28, respectively. Dogs treated with SIMPARICA had significantly (p<0.01) fewer live fleas than the controls at 6 hours post-infestation on the same days. SIMPARICA 6-hour efficacies were 100%, 100%, 98.8%, 86.6%, and 87.0% on the same days, respectively. There was no significant (p>0.05) difference in flea count between the dogs treated with FRONTLINE Gold and those treated with SIMPARICA on any of the 6-hour post-infestation assessments.