Efficacy of sarolaner (Simparica®) against induced infestations of Haemaphysalis longicornis on dogs.

BACKGROUND: Haemaphysalis longicornis is the major tick affecting dogs in most of the East Asia/Pacific region and has recently been detected in a number of areas of the USA. This tick is a vector for a number of pathogens of dogs, other mammals and humans. In this study, the efficacy of a single oral administration of sarolaner (Simparica®, Zoetis) at the minimum label dosage (2 mg/kg) was evaluated against an existing infestation of H. longicornis and subsequent weekly reinfestations for 5 weeks after treatment. METHODS: Sixteen dogs were ranked on pretreatment tick counts and randomly allocated to treatment on Day 0 with sarolaner at 2 mg/kg or a placebo. The dogs were infested with H. longicornis nymphs on Days - 2, 5, 12, 19, 26 and 33. Efficacy was determined at 48 hours after treatment and subsequent re-infestations based on live tick counts relative to placebo-treated dogs. RESULTS: There were no adverse reactions to treatment. A single dose of sarolaner provided 100% efficacy on Days 2, 7, 14 and 21; and ≥ 97.4% efficacy on Days 28 and 35. Considering only attached, live ticks, efficacy was 100% for the entire 35 days of the study. Geometric mean live tick counts for sarolaner were significantly lower than those for placebo on all days (11.62 ≤ t(df) ≤ 59.99, where 13.0 ≤ df ≤ 14.1, P < 0.0001). CONCLUSIONS: In this study, a single oral administration of sarolaner at 2 mg/kg provided 100% efficacy against an existing infestation of H. longicornis nymphs and ≥ 97.4% efficacy (100% against attached ticks) against weekly reinfestation for at least 35 days after treatment.

Efficacy and safety of a new topical formulation containing selamectin and sarolaner in the prevention of heartworm disease and the treatment of roundworm infection in cats presented as veterinary patients in Japan.

The efficacy and safety of a new topical formulation containing selamectin plus sarolaner (Revolution® Plus / Stronghold® Plus, Zoetis) was evaluated for the prevention of heartworm (Dirofilaria immitis) disease and the treatment of roundworm infection in cats enrolled as veterinary patients in two field studies conducted in Japan. In the heartworm field study, 91 cats negative for D. immitis antigen and anti-D. immitis antibody were enrolled and received 9 monthly topical treatments with selamectin plus sarolaner during the period of April to December 2015. Efficacy was assessed by testing post-treatment blood samples collected 8, 12, and 15 months after initiation of treatment for the presence of D. immitis antigen and anti-D. immitis antibody. Eighty-seven cats completed the entire study and were included in the determination of efficacy. No D. immitis antigen or anti-D. immitis antibody were detected in any of the post-treatment samples. In the roundworm field study, completed in the period from April to November 2015, 64 cats with ≥100 roundworm eggs per gram (EPG) of feces were enrolled and allocated randomly in a 1:1 ratio, to receive either selamectin plus sarolaner or emodepside plus praziquantel (Profender®, Bayer). Treatments were administered topically on Days 0 and 30, and efficacy was assessed by fecal EPG counts conducted on Days 14, 30, and 60. All cats completed the entire study. At enrollment, all cats were infected with Toxocara cati. Compared to pre-treatment, geometric mean T. cati EPG counts on Days 14, 30, and 60 were reduced by >99.9% in both treatment groups. There were no treatment-related adverse events in either study. Monthly topical administration of Revolution® Plus / Stronghold® Plus providing a minimum of 6 mg/kg selamectin and 1 mg/kg sarolaner was safe and effective in the prevention of heartworm disease and the treatment of roundworm infection in cats enrolled as veterinary patients in Japan.

Efficacy of a new topical formulation of selamectin plus sarolaner for the control of fleas and ticks infesting cats in Japan.

The efficacy of a single application of a new topical formulation containing selamectin plus sarolaner (Revolution® Plus / Stronghold® Plus, Zoetis) was evaluated against fleas and ticks infesting cats enrolled as veterinary patients in two field studies conducted in Japan and against Haemaphysalis longicornis ticks on cats in a laboratory study. In the laboratory study, sixteen cats were ranked based on pre-treatment tick counts and allocated randomly to treatment on Day 0 with either selamectin plus sarolaner or placebo. Cats were infested with adult H. longicornis on Days -2, 5, 12, 19, 26 and 33. Efficacy relative to placebo was based on live attached tick counts conducted 48 h after treatment and subsequent re-infestations. Selamectin plus sarolaner reduced live, attached H. longicornis counts by 96.4% within 48 h of treatment, and by ≥91.7% within 48 h of weekly re-infestation for 35 days, based on arithmetic means. In the field studies, 67 client-owned cats harboring six or more live fleas and 63 cats harboring four or more live attached ticks were enrolled to evaluate selamectin plus sarolaner for efficacy and safety compared with a registered product. Cats were allocated randomly to treatment with selamectin plus sarolaner or fipronil plus (S)-methoprene based on order of presentation. Treatment was administered once on Day 0 and efficacy was assessed by parasite counts conducted on Days 14 and 30 compared to the pre-treatment count. In the flea field study, live flea counts on Days 14 and 30 were reduced by 99.5% and 99.9% in the selamectin plus sarolaner group, and by 97.6% and 98.6% in the fipronil plus (S)-methoprene group, based on least squares mean percentage reductions. Clinical signs typically associated with flea allergy dermatitis improved following treatment. In the tick field study, live tick counts on Days 14 and 30 were reduced by 97.5% and 97.7% in the selamectin plus sarolaner group, and by 91.5% and 93.4% in the fipronil plus (S)-methoprene group, based on least squares mean percentage reductions. Selamectin plus sarolaner was determined to be non-inferior to fipronil plus (S)-methoprene in both field studies. There were no treatment-related adverse events in any study. A single topical dose of Revolution® Plus / Stronghold® Plus providing a minimum dosage of 6.0 mg/kg selamectin and 1.0 mg/kg sarolaner was confirmed to be effective against H. longicornis ticks on cats for one month and safe and effective in the treatment of fleas and ticks on cats enrolled as veterinary patients in Japan.