title: Efficacy of afoxolaner plus milbemycin oxime chewable tablets against naturally acquired intestinal nematodes in dogs.
abstract: The efficacy of oral afoxolaner plus milbemycin oxime combination chewable tablets (NexGard Spectra, Merial) against naturally acquired intestinal nematode infections in dogs was evaluated in six negative control, blinded studies including a total of 114 dogs. Dogs were selected based on a pre-treatment fecal examination indicating patent infections with hookworms (two studies), Toxocara or Toxascaris ascarids (one study each) or Trichuris whipworms (two studies). In each study, dogs were assigned to blocks of two animals each, based on decreasing pre-treatment body weight and were randomly allocated to one of two groups consisting of eight, nine or 10 dogs: untreated (control) or treated with the combination chewable tablet formulation. Chewable tablets were combined to provide doses of actives as close as possible to the minimum effective dose of afoxolaner and milbemycin oxime, i.e., 2.5 mg/kg body weight and 0.5 mg/kg body weight, respectively, once on Day 0. For parasite recovery and count, dogs were euthanized humanely and necropsied seven or eight days after treatment. A single treatment with afoxolaner plus milbemycin oxime chewable tablets provided 94.8% and 90.9% efficacy against adult Ancylostoma braziliense and A. caninum, respectively, 97.8% and 99.4% efficacy against adult Toxocara canis and Toxascaris leonina, respectively, and ≥98.3% efficacy against adult Trichuris vulpis. Compared to untreated controls, nematode counts of the treated dogs were significantly reduced (F-test; p<0.002). In addition, analysis of the pooled data across studies revealed that treatment with afoxolaner plus milbemycin oxime chewable tablets reduced adult Uncinaria stenocephala burdens by 74.9% (p=0.002). All dogs tolerated the treatment well based on clinical observations post-treatment and daily clinical observations. No adverse experiences or other clinical problems related to the treatment were observed throughout the studies. The results of this series of controlled studies demonstrated high efficacy and excellent acceptability and safety of the afoxolaner plus milbemycin oxime chewable tablets when administered for treatment of a broad range of canine intestinal nematode infections.
authors.affiliation: Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany. Electronic address: steffen.rehbein@merial.com.
authors.forename: Steffen
authors.initials: S
authors.lastname: Rehbein
authors.affiliation: Merial, Inc., Missouri Research Center, 6498 Jade Road, Fulton, MO 65251, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Dorr
authors.affiliation: Cheri Hill Kennel & Supply, Inc., 17190 Polk Road, Stanwood, MI, USA.
authors.forename: Dwight D
authors.initials: DD
authors.lastname: Bowman
authors.affiliation: ClinVet International (Pty) Ltd., Uitsig Road, Bainsvlei, 9321 Bloemfontein, South Africa; University of Johannesburg, c/o Kingsway and University Road, Aucklandpark, Jonannesburg, South Africa.
authors.forename: Dionne
authors.initials: D
authors.lastname: Crafford
authors.affiliation: Universiteti Bujqësor, Fakulteti i Mjekësisë Veterinare, Kodër Kamëz, Tirana, Albania.
authors.forename: Ilir
authors.initials: I
authors.lastname: Kusi
authors.affiliation: Universiteti Bujqësor, Fakulteti i Mjekësisë Veterinare, Kodër Kamëz, Tirana, Albania.
authors.forename: Rezart
authors.initials: R
authors.lastname: Postoli
authors.affiliation: Merial, Inc., 3239 Satellite Blvd., Duluth, GA 30096, USA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Yoon
authors.affiliation: Merial, Inc., 3239 Satellite Blvd., Duluth, GA 30096, USA.
authors.forename: S Theodore
authors.initials: ST
authors.lastname: Chester
authors.affiliation: Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany.
authors.forename: Doris
authors.initials: D
authors.lastname: Dollhofer
authors.affiliation: Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Visser
authors.affiliation: Merial, Inc., 3239 Satellite Blvd., Duluth, GA 30096, USA.
authors.forename: Diane L
authors.initials: DL
authors.lastname: Larsen
mesh_terms: D000284:Administration, Oral; D000818:Animals; D004283:Dog Diseases / Q000188:drug therapy*; D004285:Dogs; D018942:Macrolides / Q000008:administration & dosage*; D009348:Nematoda / Q000502:physiology; D009349:Nematode Infections / Q000188:drug therapy / Q000662:veterinary*; D059208:Parasite Load / Q000662:veterinary; D011897:Random Allocation; D013607:Tablets; D016896:Treatment Outcome
chemical_list: D018942:Macrolides; D013607:Tablets; C078973:milbemycin oxime
keywords: Afoxolaner; Ancylostoma braziliense; Ancylostoma caninum; Dog; Milbemycin oxime; Toxascaris leonina; Toxocara canis; Trichuris vulpis