{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T18:41:34Z","timestamp":1776192094171,"version":"3.50.1"},"reference-count":23,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2023,11,13]],"date-time":"2023-11-13T00:00:00Z","timestamp":1699833600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008771","name":"Animal and Plant Quarantine Agency","doi-asserted-by":"publisher","award":["B-1543069-2023-25-02"],"award-info":[{"award-number":["B-1543069-2023-25-02"]}],"id":[{"id":"10.13039\/501100008771","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The recent expiration of patents for the antibiotic tulathromycin has led to a significant increase in the number of generic tulathromycin products (GTPs) available. This study aims to evaluate the bioequivalence of four GTPs, which experienced a rapid increase in market share. The bioequivalence was evaluated by performing pharmacokinetic assessments. The four selected GTPs (Tulaject, Tulagen, Toulashot, and T-raxxin) were compared with the reference product, Draxxin. A dose of 2.5 mg\/kg.bw\/day was administered via subcutaneous injection, and blood samples were collected 460 times from 20 Holstein cattle. Plasma concentrations of tulathromycin were measured over time using LC-MS\/MS analysis. Bioequivalence was evaluated using a statistical program for pharmacokinetic parameters, including the area under the concentration time curve (AUC) and the maximum plasma concentration (Cmax). The bioequivalence was considered proven if the difference between the test and reference products was within 20% for both AUC and Cmax. The results showed that the confidence interval (CI, 90%) for both AUC and Cmax values was within the 80~120% range, demonstrating the bioequivalence of the four GTPs compared to Draxxin. This study provides evidence for the bioequivalence of the selected GTPs, contributing to their validation for use as effective antibiotics.<\/jats:p>","DOI":"10.3390\/ijms242216262","type":"journal-article","created":{"date-parts":[[2023,11,13]],"date-time":"2023-11-13T08:35:52Z","timestamp":1699864552000},"page":"16262","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Evaluation of Biological Equivalence for Generic Tulathromycin Injections in Cattle"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2097-6137","authenticated-orcid":false,"given":"JeongWoo","family":"Kang","sequence":"first","affiliation":[{"name":"Animal Disease Diagnosis Division, Animal and Plant Quarantine Agency (APQA), Ministry of Agriculture, Food and Rural Affairs, 177, Hyeoksin 8-ro, Gimcheon-si 39660, Gyeongsangbuk-do, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"HyunYoung","family":"Chae","sequence":"additional","affiliation":[{"name":"Animal Disease Diagnosis Division, Animal and Plant Quarantine Agency (APQA), Ministry of Agriculture, Food and Rural Affairs, 177, Hyeoksin 8-ro, Gimcheon-si 39660, Gyeongsangbuk-do, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"SungHoon","family":"Jeong","sequence":"additional","affiliation":[{"name":"Veterinary Drugs & Biologics Division, Animal and Plant Quarantine Agency (APQA), Ministry of Agriculture, Food and Rural Affairs, 177, Hyeoksin 8-ro, Gimcheon-si 39660, Gyeongsangbuk-do, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rokeya","family":"Pervin","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, College of Medicine, University of Illinois Chicago, 835 S. Wolcott Ave (MC790), Chicago, IL 60612, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7131-4814","authenticated-orcid":false,"given":"Md Akil","family":"Hossain","sequence":"additional","affiliation":[{"name":"Institute for Tuberculosis Research, College of Pharmacy, University of Illinois Chicago, 833 S. Wood St. (MC964), Chicago, IL 60612, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,13]]},"reference":[{"key":"ref_1","first-page":"245","article-title":"Antimicrobial activity of tulathromycin against contemporary pathogens isolated from North American and European hospitals","volume":"52","author":"Jones","year":"2005","journal-title":"Diagn. Microbiol. Infect. Dis."},{"key":"ref_2","first-page":"455","article-title":"Species differences in pharmacokinetics and pharmacodynamics","volume":"25","author":"Toutain","year":"2002","journal-title":"J. Vet. 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Sci."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/24\/22\/16262\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T21:22:18Z","timestamp":1760131338000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/24\/22\/16262"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,11,13]]},"references-count":23,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2023,11]]}},"alternative-id":["ijms242216262"],"URL":"https:\/\/doi.org\/10.3390\/ijms242216262","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,11,13]]}}}