Efficacy of sarolaner, a novel oral isoxazoline, against two common mite infestations in dogs: Demodex spp. and Otodectes cynotis

• Oral sarolaner was effective against Demodex spp. and Otodectes cynotis in dogs.
• Demodex were reduced by 99.8% and 100% after the first and second monthly doses.
• Clinical signs of demodicosis were markedly improved following sarolaner treatment.
• Otodectes cynotis mites were reduced by 98.2% after a single dose.

The efficacy of sarolaner (Simparica™, Zoetis) was evaluated against Demodex spp. in dogs with generalized demodicosis and against Otodectes cynotis (otodectic mange) in dogs with induced infestations.In the first study, 16 dogs with clinical signs of generalized demodicosis and positive for Demodex spp. mites were randomly assigned to treatment with either sarolaner (2 mg/kg) orally on Days 0, 30 and 60, or topical imidacloprid (10 mg/kg) plus moxidectin (2.5 mg/kg) solution every 7 days from Day 0 to Day 81. For sarolaner-treated dogs, pretreatment mite counts were reduced by 97.1% at 14 days and 99.8% by 29 days after the first dose, with no live mites detected thereafter. Weekly imidacloprid plus moxidectin resulted in 84.4 and 95.6% reduction at these two time points, respectively, with no mites detected from Day 74 on. All dogs in both groups showed marked improvement in the clinical signs of demodicosis.In the second study, 32 dogs with induced infestations of O. cynotis were randomly assigned (eight per group) to oral sarolaner (2 mg/kg) as a single treatment on Day 0 or as a two dose regime (Days 0 and 30), or a placebo group for each of the dose regimes. Sarolaner administered at 2 mg/kg as a single oral dose resulted in a 98.2% reduction at Day 30 and two doses of sarolaner, administered one month apart, resulted in a 99.5% reduction in ear mites at Day 60 compared to placebo controls. There were no treatment related adverse events in either study.In these studies, sarolaner at an oral dose of 2 mg/kg was highly effective in reducing the live mite counts associated with a natural infestation of Demodex spp. and an induced infestation of O. cynotis. In addition, the Demodex-infested dogs showed a marked improvement in the clinical signs of generalized demodicosis.