Field efficacy and safety evaluation of a novel chewable tablet (Credelio Quattro™) containing lotilaner, moxidectin, praziquantel, and pyrantel against gastrointestinal nematode infections in dogs in the USA

Abstract Background Gastrointestinal nematodes such as hookworms (Ancylostoma caninum) and roundworms (Toxocara canis) commonly infect dogs and are zoonotic parasites capable of producing clinical disease in humans. This field study was conducted to confirm the clinical effectiveness and field safety of a novel, chewable tablet (Credelio Quattro™) containing lotilaner, moxidectin, praziquantel, and pyrantel (as pamoate salt) as compared with a control product containing sarolaner, moxidectin, and pyrantel (as pamoate salt) for the treatment of naturally occurring gastrointestinal nematode infections in dogs. Methods In this multicenter field study, 158 dogs were enrolled with an evaluable safety population of 155 dogs and an evaluable effectiveness population of 109 dogs. Dogs were randomized in a 2:1 ratio to receive either the investigational veterinary product (IVP) Credelio Quattro containing lotilaner, moxidectin, praziquantel, and pyrantel or the control product (CP) containing sarolaner, moxidectin, and pyrantel. On Day 0, after confirmation of infection, enrolled dogs were randomized, dispensed, and administered IVP or CP. Enrolled dogs returned to the study site on Day 10 (± 2 d) to quantify the concentration of nematode eggs post-treatment. Results Post-treatment fecal egg counts performed on Day 10 demonstrated a 99.9% reduction in A. caninum eggs per gram in both IVP-treated dogs and CP-treated dogs. In addition, a 98.7% and 96.6% reduction in T. canis fecal egg counts were observed in IVP- and CP-treated dogs, respectively. Adverse events were reported in both treatment groups. The most common adverse events reported in the IVP group included gastrointestinal signs, such as diarrhea and emesis, as well as lethargy. Conclusions This field study demonstrated that Credelio Quattro, a novel oral combination chewable tablet administered at the labeled dose ranges of 20–40 mg/kg lotilaner, 0.02–0.04 mg/kg moxidectin, 5–10 mg/kg praziquantel, and 5–10 mg/kg pyrantel (as pamoate salt), is safe and effective for the treatment and control of naturally occurring A. caninum and T. canis infections in dogs. Graphical Abstract