{"doi":"10.2460/ajvr.25.01.0027","title":"Topical and oral emodepside formulations for last-line treatment of multianthelmintic drug-resistant hookworms when given orally to dogs are not bioequivalent","abstract":"Objective: To evaluate the pharmacokinetics of emodepside in dogs following single-dose administration of the FDA-approved feline topical solution orally and topically and the European Medicines Agency-approved canine modified-release tablet orally and to assess the bioequivalence of the feline topical solution administered orally compared to the canine modified-release tablet. Methods: This study was conducted in 3 phases, during which dogs received single doses of emodepside as the feline topical solution (1 mg/kg) orally, the canine modified-release tablet (1 mg/kg) orally, and the topical feline solution (3 mg/kg) topically. Plasma pharmacokinetic profiles were determined for 21 days postdose. Bioequivalence testing was conducted for orally administered emodepside. Results: 7 healthy client-owned dogs (4 female and 3 male) were prospectively enrolled in this crossover study from May through August 2023. Oral administration of the feline topical solution resulted in markedly greater emodepside absorption than the modified-release tablet and was not bioequivalent. Emodepside plasma concentrations following topical administration of the FDA formulation were 36- to 122-fold lower than after oral administration. Conclusions: The feline topical solution administered orally at 1 mg/kg is not bioequivalent to the canine modified-release tablet. Markedly higher absorption of the feline topical solution administered orally raises potential safety concerns for extralabel use in dogs to treat multianthelmintic drug-resistant hookworm infections. Poor absorption following topical administration suggests it may be unsuitable for treating multianthelmintic drug-resistant hookworm infections. Clinical Relevance: These findings highlight potential emodepside toxicity risks with extralabel use of the FDA-approved topical feline product and help inform safe off-label use in dogs.","journal":"American Journal of Veterinary Research","year":2025,"id":531284,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":4,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9579,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1412019,"name":"Greta N. Karwath","orcid":null,"position":1,"is_corresponding":false},{"id":1143431,"name":"Erin J. Mayhue","orcid":null,"position":2,"is_corresponding":false},{"id":1143109,"name":"Maria C. Jugan","orcid":"0000-0002-6963-7646","position":3,"is_corresponding":false},{"id":433989,"name":"Jeba R. J. Jesudoss Chelladurai","orcid":"0000-0003-3077-0201","position":4,"is_corresponding":false},{"id":492815,"name":"Stephanie E. Martinez","orcid":"0000-0001-8430-4973","position":5,"is_corresponding":false},{"id":1095898,"name":"Theresa A. Quintana","orcid":"0000-0003-1266-3349","position":0,"is_corresponding":true}],"reference_count":26,"raw_metadata":null,"created_at":"2026-07-19T02:51:14.579161Z","pmid":"40185127","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}