Assessment of lotilaner (Credelio® CAT) for control of in-home Ctenocephalides felis infestations.

BACKGROUND: Flea infestations remain a major issue in veterinary medicine. Highly effective flea control for dogs and cats remains the foundation for eliminating infestations from homes and improving skin conditions associated with flea-feeding. METHODS: Homes with pet cats were screened by flea-history questionnaire. Qualifying homes were subselected into "high" (≥ 5 fleas on ≥ 1 cat, and ≥ 5 fleas collected in environmental flea traps over a 16-24 h period), "low" (< 5 fleas on all cats, < 5 in traps), and "no" homes (no evidence of fleas on cats or traps). All cats and dogs in a household were treated with a lotilaner oral tablet (Credelio® CAT and Credelio®, respectively) in weeks 0, 4, and 8. On-animal and trap counts were performed for: "high" at weeks 0, 1, 2, 4, 6, 8, and 11-12; "low" at week 0 and at approximately 2-week intervals through week 11-12; and "no" only at week 0. During each visit, one owner completed a pruritus assessment (PVAS) and a veterinary dermatologist assessed dermatologic lesions using the feline allergic dermatitis (SCORFAD) scale. RESULTS: A total of 46 homes met inclusion criteria and completed the study: 19 "high" (35 cats); 17 "low" (27); and 10 "no" (14). By week 1, relative to pretreatment, there was a 99.3% reduction in flea counts on "high" cats, with 31 of 34 cats (91.2%) flea-free. By week 11-12, flea counts across all study cats and traps were zero. Prior to the first treatment, mean PVAS scores were: "high" 6.6; "low" 5.5; and "no" 1.9. By week 1 there was a significant decrease in mean PVAS score of cats from "high" homes to 2.9 (P < 0.0001), and mean week 11-12 scores were 0.5 and 0.8 for "high" and "low" homes, respectively. For SCORFAD, by week 11-12, relative to week 0, there was a significant decline in mean scores of cats from both "high" (8.0 to 1.7) (P < 0.0001) and "low" homes (3.3 to 0.9) (P < 0.0001). CONCLUSIONS: Lotilaner was 100% efficacious in eliminating flea infestations from animals and their homes. The monthly lotilaner treatments of cats and dogs in flea-infested homes resulted in clinical resolution of pruritus and dermatologic lesions.