Efficacy of fipronil/(S)-methoprene/eprinomectin/praziquantel (Broadline®) against Thelazia callipaeda in naturally infected cats

Abstract

Background The present clinical field trial was conducted to assess the efficacy of a broad-spectrum parasiticide spot-on formulation containing eprinomectin (Broadline®) against Thelazia callipaeda eyeworm in naturally infected cats. Methods Fifteen privately owned cats harboring at least one live adult T. callipaeda were included in the study. Cats were randomly allocated to an untreated control group of seven cats or to a Broadline®-treated group of eight cats. Cats were treated on Day 0; ocular examinations were performed at inclusion and on Days 7 and 14; eyeworms were recovered and counted on Day 14. The primary efficacy assessment was based on group comparison of number of T. callipaeda on Day 14. Results Seven days after treatment, six of eight treated cats were negative for eyeworm infection per visual examination, and on Day 14 no eyeworms were found in the treated cats while the seven untreated cats were still infected (geometric mean: 1.97). All cats had inflammatory ocular signs at inclusion; on Day 14, five of eight treated cats had recovered while all untreated control cats were still symptomatic. All collected parasites were confirmed to be T. callipaeda by morphology and molecular characterization. Conclusions A single treatment with Broadline® provided 100% efficacy against feline thelaziosis and improved related ocular inflammation signs. Graphical abstract

Efficacy of a combination of esafoxolaner, eprinomectin and praziquantel (NexGard® Combo) against Thelazia callipaeda in naturally infected cats

“…An oral product containing milbemycin oxime had an efficacy of 53.3% after a single treatment and of 73.3% after two treatments 2 weeks apart [ 14 ]. A spot-on formulation containing fipronil, (S)-methoprene, eprinomectin and praziquantel (Broadline TM ) proved 100% efficacy within 2 weeks after a single treatment [ 28 ]. This latter product contains the same amount of eprinomectin and praziquantel as NexGard ® Combo and, accordingly, the results herein presented are consistent with what was observed in the previous efficacy study [ 28 ].…”

“…The ratio treated cats:untreated control was 1:1. The study was conducted in an area of northern Italy where T. callipaeda was previously observed in domestic and wild animals [ 18 , 28 ]. Approval to conduct the study was obtained from the Italian regulatory authority (Italian Health Ministry, authorization no.…”

“…Clinical pictures of feline thelaziosis can vary in severity, ranging from subclinical cases to clinical signs such as tearing, eye scratching and inflammation, conjunctivitis, keratitis, blepharospasm, purulent exudations, and corneal ulcers [ 11 , 28 ].…”

“…Timely and accurate diagnosis, followed by an effective therapeutic approach, is pivotal to safeguard animal health and reduce the circulation of T. callipaeda among intermediate and definitive hosts [ 28 ]. Nonetheless, there are limited treatment choices available for feline thelaziosis [ 14 , 22 ], even though the confirmation of the efficacy of the macrocyclic lactone eprinomectin against the infection in cats is noteworthy [ 28 ].…”

Efficacy of a formulation of sarolaner/moxidectin/pyrantel (Simparica Trio®) for the prevention of Thelazia callipaeda canine eyeworm infection

“…Studies on the efficacy of diverse chemical compounds against T. callipaeda infection have been performed in dogs [ 16 – 20 , 31 ] and cats [ 17 , 32 ] using several formulations, including moxidectin 2.5% and imidacloprid 10% [ 18 ], milbemycin oxime/praziquantel [ 17 ], milbemycin oxime/afoxolaner [ 19 ], and fipronil/(S)-methoprene/eprinomectin/praziquantel [ 32 ]. Here, the oral formulation (minimal commercial dose of 1.2 mg/kg sarolaner, 24 µg/kg moxidectin, and 5 mg/kg pyrantel) has been proved 100% efficacious in preventing eyeworm infections in dogs, adding a new option available in the market for the prevention of T. callipaeda eyeworm infections.…”