Efficacy and safety of a new spot-on formulation of selamectin plus sarolaner in the treatment of naturally occurring flea and tick infestations in cats presented as veterinary patients in Europe

In the flea study, 277 cats were assessed for efficacy and safety, and an additional 170 cats were assessed for safety only. On days 14, 30, 60 and 90, efficacy against fleas was 97.4%, 97.3%, 98.8% and 99.4% in the selamectin/sarolaner-treated group and was 90.0%, 83.6%, 87.7% and 96.3% in the imidacloprid/moxidectin-treated group, respectively. Selamectin/sarolaner was non-inferior to imidacloprid/moxidectin at all time-points. For the 16 cats identified as having FAD at enrolment, clinical signs related to FAD improved following treatment administration. In the tick study, 200 cats were assessed for efficacy and safety, and a further 70 cats were assessed for safety only. Four tick species were identified. Overall efficacy against ticks was 96.7%, 92.6%, 98.8% and 99.5% in the selamectin/sarolaner-treated group and was 90.2%, 74.6%, 83.0% and 93.4% in the fipronil-treated group on Days 14, 30, 60 and 90, respectively. Selamectin/sarolaner was non-inferior to fipronil at all time-points, and was superior on Days 30 and 60. There were no serious treatment-related adverse events in any study. Thus, the new spot-on formulation of selamectin plus sarolaner administered at monthly intervals was safe and highly effective against natural infestations of fleas and ticks on cats, and improved clinical signs of FAD.