Efficacy of a novel chewable tablet (Credelio Quattro) containing lotilaner, moxidectin, praziquantel, and pyrantel against Toxocara canis and Toxascaris leonina infections in dogs.

Background: Roundworms such as Toxascaris leonina and Toxocara canis are routinely diagnosed in dogs globally, especially in dogs 6 months of age or younger. Toxocara canis is zoonotic, can cause significant disease in dogs, and is the causative agent of toxocariasis in humans. To protect both animal and human health, it is imperative that Toxocara canis infections are effectively treated and controlled to minimize the risk of transmission. The following studies were performed to demonstrate the effectiveness and safety of a novel, combination chewable tablet (Credelio Quattro) containing the minimum effective dosages of lotilaner (20.0 mg/kg), moxidectin (0.02 mg/kg), praziquantel (5.0 mg/kg), and pyrantel (5.0 mg/kg) for the treatment and control of T. canis and T. leonina infections in dogs.

Methods: Six well-controlled studies were performed. Two studies each evaluated Credelio Quattro against immature adult T. canis, adult T. canis, and adult T. leonina infections. Post-treatment efficacy was calculated from necropsy worm counts, and fecal egg count reduction was determined 10 days post-treatment in studies evaluating experimentally induced or naturally acquired adult infections.

Results: Credelio Quattro was safe and ≥ 97.9% effective against immature adult stages and ≥ 97.0% effective against adult stages of induced and natural T. canis infections in dogs. After treatment with Credelio Quattro, fecal egg counts were reduced by ≥ 98.8% in T. canis-infected dogs. In both experimentally induced and naturally acquired adult T. leonina infections in dogs, Credelio Quattro was safe and 100% effective in eliminating adult worms and provided 100% reduction in fecal egg counts post-treatment. The most common adverse events reported included digestive tract disorders such as diarrhea, mucus and/or blood in feces, vomiting, and expelled ascarid worms, which occurred in both control- and treated-groups.

Conclusions: These laboratory studies confirm the effectiveness and safety of a single dose of Credelio Quattro, administered at the minimum dosages of 20 mg/kg lotilaner, 0.02 mg/kg moxidectin, 5 mg/kg praziquantel, and 5 mg/kg pyrantel, for the treatment and control of immature adult and adult T. canis and adult T. leonina in dogs.