Efficacy of a novel oral formulation of sarolaner (Simparica™) against five common tick species infesting dogs in the United States

Abstract

The efficacy of a single oral treatment with sarolaner (Simparica™, Zoetis), a novel isoxazoline compound, was evaluated against five tick species known to infest dogs in the United States. A total of 10 laboratory studies, two against each species, were conducted using adult purpose-bred mongrels or Beagle dogs. In each study, 16 dogs were randomly allocated to one of two treatment groups based on pre-treatment host-suitability tick counts. Dogs were infested with approximately 50 unfed adult Amblyomma americanum, Amblyomma maculatum, Dermacentor variabilis, Ixodes scapularis or Rhipicephalus sanguineus ticks on Days -2, 5, 12, 19, 26 and 33. On Day 0, dogs were treated with a placebo or a sarolaner tablet providing a minimum dose of 2 mg/kg. Tick counts were conducted 48h after treatment and after each subsequent weekly re-infestation. There were no treatment-related adverse reactions during any of the studies. Dogs in the placebo-treated group maintained tick infestations throughout the studies. Geometric mean live tick counts were significantly lower (P≤0.0001) in the sarolaner-treated group compared to the tick counts in the placebo group at all timepoints. Treatment with sarolaner resulted in ≥99.6% efficacy against existing infestations of all five tick species within 48h. The efficacy against weekly post-treatment re-infestations of all tick species was ≥96.9% for at least 35 days after treatment. Thus, a single dose of sarolaner administered orally at the minimum dosage of 2mg/kg, resulted in excellent efficacy within 48h against existing tick infestations, and against weekly re-infestations for 35 days after treatment. These studies confirmed that administration of the minimum dose of sarolaner will provide rapid treatment of existing infestations and give at least one month of control against re-infestation by the common tick species affecting dogs in the US.

Laboratory evaluations of the immediate and sustained efficacy of lotilaner (Credelio™) against four common species of ticks affecting dogs in North America

“…For instance, lotilaner efficacy was 100% against R. sanguineus and I. scapularis in at least 50% of post-treatment challenges. Another isoxazoline, sarolaner achieved similar results against these tick species, based on 48-h counts, through at least 1 month after treatment [ 13 ]. In contrast, afoxolaner, also an isoxazoline, did not achieve 100% efficacy 48 h after any post-treatment challenge in two studies with R. sanguineus [ 14 ] .…”

Efficacy of sarolaner (Simparic™) against induced infestations of Amblyomma cajennense on dogs

“…The efficacy observed against A. cajennense in this study, 100% within 48 h of treatment of an existing infestation, and ≥ 99.6% within 48 h of weekly re-infestation for 35 days, is comparable with the efficacies reported for sarolaner against other tick species commonly found on dogs. Six et al [ 21 ] showed that sarolaner provided ≥ 99.6% efficacy within 48 h of treatment and ≥ 99.6% efficacy within 48 h after weekly re-infestation for 35 days against Amblyomma americanum , Amblyomma maculatum , Dermacentor variabilis , Ixodes scapularis and Rhipicephalus sanguineus . Similarly, Geurden et al [ 23 ] showed that sarolaner provided ≥ 99.7% efficacy within 48 h of treatment and ≥ 97.5% efficacy within 48 h after weekly re-infestation for 35 days against Dermacentor reticulaus , Ixodes hexagonus , I. ricinus and R. sanguineus.…”

Efficacy of oral sarolaner for the treatment of generalized demodicosis in dogs

“…This drug has high palatability and is fully and voluntarily consumed within 1 minute in 90.5% of cases (Becskei et al, 2016). No severe adverse effects were observed by earlier studies (Becskei et al, 2016;Mctier et al, 2016a;Six et al, 2016a;Six et al, 2016b).…”