{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T05:04:00Z","timestamp":1790226240448,"version":"4.1.0"},"reference-count":11,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T00:00:00Z","timestamp":1790121600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T00:00:00Z","timestamp":1790121600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Vet Pharm &amp; Therapeutics"],"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>Because P\u2010glycoprotein (P\u2010gp) influences the disposition of substrate drugs, regulatory agencies recommend ascertaining the P\u2010gp substrate status of active pharmaceutical ingredients (API's) intended for humans. Transwell\u2010based assays using P\u2010gp\u2010overexpressing human cell lines are routinely used to predict the API's P\u2010gp substrate status. Although ABCB1\u20101\u0394\u2010mediated P\u2010gp deficiency contributes to serious canine adverse drug reactions, assessment of canine P\u2010gp status is not currently recommended by regulatory agencies for canine API's. We have previously employed a competitive efflux assay to assess drugs as canine P\u2010gp substrates as it affords some advantages over transwell assays. Our objective was to preliminarily compare results generated from these two methods using historical data for transwell assays. Eleven drugs were assessed as canine P\u2010gp substrates by both methods, with two identified as non\u2010P\u2010gp substrates (erythromycin, propranolol) and nine identified as canine P\u2010gp substrates (clarithromycin, daunorubicin, digoxin, etoposide, paclitaxel, quinidine, ritonavir, verapamil, vinblastine). Erythromycin was identified as a canine P\u2010gp substrate by competitive efflux assay at roughly 10\u2010fold higher concentrations than was used for transwell assays. Concordance of these methods assessing canine P\u2010gp substrate status using historical data supports the need for head\u2010to\u2010head studies comparing these two methods for identifying canine P\u2010gp substrates.<\/jats:p>","DOI":"10.1111\/jvp.70110","type":"journal-article","created":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T04:51:21Z","timestamp":1790225481000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Preliminary Comparison of Competitive Efflux and Historical Transwell Assays for Assessing Canine P\u2010Glycoprotein Substrate Status of Eleven Drugs Representing Ten Different Drug Classes"],"prefix":"10.1111","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1614-2903","authenticated-orcid":false,"given":"K. L.","family":"Mealey","sequence":"first","affiliation":[{"name":"Program in Individualized Medicine (PrIMe), College of Veterinary Medicine Washington State University  Pullman Washington USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"N. S.","family":"Burke","sequence":"additional","affiliation":[{"name":"Program in Individualized Medicine (PrIMe), College of Veterinary Medicine Washington State University  Pullman Washington USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,9,23]]},"reference":[{"key":"e_1_2_7_2_1","doi-asserted-by":"publisher","DOI":"10.1111\/jvp.13386"},{"key":"e_1_2_7_3_1","doi-asserted-by":"publisher","DOI":"10.3389\/fphar.2024.1412692"},{"key":"e_1_2_7_4_1","doi-asserted-by":"publisher","DOI":"10.2460\/ajvr.25.11.0419"},{"key":"e_1_2_7_5_1","doi-asserted-by":"publisher","DOI":"10.1111\/jvp.70034"},{"key":"e_1_2_7_6_1","doi-asserted-by":"publisher","DOI":"10.1111\/jvp.13123"},{"key":"e_1_2_7_7_1","doi-asserted-by":"publisher","DOI":"10.1111\/jvp.12390"},{"key":"e_1_2_7_8_1","doi-asserted-by":"publisher","DOI":"10.1111\/jvp.13102"},{"key":"e_1_2_7_9_1","doi-asserted-by":"publisher","DOI":"10.1111\/jvp.70041"},{"key":"e_1_2_7_10_1","doi-asserted-by":"publisher","DOI":"10.1007\/s11095\u2010006\u20100285\u20107"},{"key":"e_1_2_7_11_1","doi-asserted-by":"publisher","DOI":"10.1002\/cpt.2701"},{"key":"e_1_2_7_12_1","doi-asserted-by":"publisher","DOI":"10.1002\/jps.22566"}],"container-title":["Journal of Veterinary Pharmacology and Therapeutics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/jvp.70110","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1111\/jvp.70110","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/jvp.70110","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T04:51:28Z","timestamp":1790225488000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/jvp.70110"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,23]]},"references-count":11,"alternative-id":["10.1111\/jvp.70110"],"URL":"https:\/\/doi.org\/10.1111\/jvp.70110","archive":["Portico"],"relation":{},"ISSN":["0140-7783","1365-2885"],"issn-type":[{"value":"0140-7783","type":"print"},{"value":"1365-2885","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,23]]},"assertion":[{"value":"2026-06-03","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-15","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-23","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"jvp.70110"}}