{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T11:17:44Z","timestamp":1788261464523,"version":"build-2803163510"},"reference-count":35,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Pharmacol."],"abstract":"\n Background<\/jats:title>\n Onradivir (ZSP1273) is a novel inhibitor of the RNA polymerase PB2 subunit of influenza A virus, developed for the treatment of acute uncomplicated influenza A. The onradivir tablet, launched in 2023, is intended for adult patients and is not suitable for children. This project aims to evaluate the pharmacokinetic profile of the onradivir granule formulation, providing evidence to support its use in the target pediatric population as well as in adult patients.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n This study adopted a open, four-period, repeated crossover design. Thirty-two healthy adult males received 200\u00a0mg doses of either the onradivir granules or onradivir tablets under fasting conditions. To quantify the plasma concentration of onradivir using an LC-MS\/MS method and evaluate its pharmacokinetic parameters.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n During the trial, no SAEs or SUSARs occurred in any participants. The coefficient of variation for C\n max<\/jats:sub>\n of the onradivir tablets was 74.91%, indicating high variability and necessitating the use of the RSABE method for evaluating C\n max<\/jats:sub>\n equivalence between the two formulations. Within-subject standard deviation of the reference formulation (S\n WR<\/jats:sub>\n ) value of C\n max<\/jats:sub>\n was 0.667, exceeding the cutoff of 0.294. C\n max<\/jats:sub>\n met both acceptance criteria: its 95% upper confidence bound, at \u22120.1769, was &lt;0, and the point estimate of the least-squares geometric mean ratio is 81.58%, fell within the 80.00%\u2013125.00% range, meeting the RSABE equivalence determination criteria; The coefficients of variation for AUC\n 0-t<\/jats:sub>\n and\n \n \n \n \n AUC<\/mml:mtext>\n \n 0<\/mml:mn>\n \u2212<\/mml:mo>\n \u221e<\/mml:mi>\n <\/mml:mrow>\n <\/mml:msub>\n <\/mml:mrow>\n <\/mml:math>\n <\/jats:inline-formula>\n of the onradivir tablets were 18.11% and 15.47%, respectively; therefore, the ABE method was employed to assess the equivalence of AUC\n 0-t<\/jats:sub>\n and\n \n \n \n \n AUC<\/mml:mtext>\n \n 0<\/mml:mn>\n \u2212<\/mml:mo>\n \u221e<\/mml:mi>\n <\/mml:mrow>\n <\/mml:msub>\n <\/mml:mrow>\n <\/mml:math>\n <\/jats:inline-formula>\n . The geometric mean ratios and 90% confidence intervals for AUC\n 0-t<\/jats:sub>\n and\n \n \n \n \n AUC<\/mml:mtext>\n \n 0<\/mml:mn>\n \u2212<\/mml:mo>\n \u221e<\/mml:mi>\n <\/mml:mrow>\n <\/mml:msub>\n <\/mml:mrow>\n <\/mml:math>\n <\/jats:inline-formula>\n were 98.13% and 97.52%, with their corresponding 90% confidence intervals of 93.91%\u2013102.54% and 93.22%\u2013102.03%, respectively, all falling within the 80.00%\u2013125.00% range, meeting the ABE equivalence determination criteria.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n The two formulations demonstrated comparable bioavailability and met the criteria for bioequivalence.<\/jats:p>\n <\/jats:sec>\n \n Clinical Trial Registration<\/jats:title>\n \n https:\/\/www.chinadrugtrials.org.cn\/clinicaltrials.searchlistdetail.dhtml<\/jats:ext-link>\n , identifier CTR20242821.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.3389\/fphar.2026.1905152","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T10:43:23Z","timestamp":1788259403000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Bioavailability of a novel anti-influenza agent, onradivir granules, in healthy Chinese adults: a first-in-human study"],"prefix":"10.3389","volume":"17","author":[{"given":"Xiaoyi","family":"Yi","sequence":"first","affiliation":[{"name":"Department of Phase I Clinical Trial Unit, Jiangxi Cancer Hospital & Institute (The Second Affiliated Hospital of Nanchang Medical College)","place":["Nanchang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuting","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Phase I Clinical Trial Unit, Jiangxi Cancer Hospital & Institute (The Second Affiliated Hospital of Nanchang Medical College)","place":["Nanchang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaosong","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Phase I Clinical Trial Unit, Jiangxi Cancer Hospital & Institute (The Second Affiliated Hospital of Nanchang Medical College)","place":["Nanchang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yahui","family":"Peng","sequence":"additional","affiliation":[{"name":"Department of Phase I Clinical Trial Unit, Jiangxi Cancer Hospital & Institute (The Second Affiliated Hospital of Nanchang Medical College)","place":["Nanchang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jian","family":"Fu","sequence":"additional","affiliation":[{"name":"Guangdong Raynovent Biotech Co., Ltd.","place":["Guangdong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Youyun","family":"Li","sequence":"additional","affiliation":[{"name":"Guangdong Raynovent Biotech Co., Ltd.","place":["Guangdong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haijun","family":"Li","sequence":"additional","affiliation":[{"name":"Guangdong Raynovent Biotech Co., Ltd.","place":["Guangdong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Phase I Clinical Trial Unit, Jiangxi Cancer Hospital & Institute (The Second Affiliated Hospital of Nanchang Medical College)","place":["Nanchang, China"]},{"name":"Jiangxi Key Laboratory of Translational Research for Cancer, Jiangxi Clinical Research Center for Cancer","place":["Nanchang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,1]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"2400199","DOI":"10.2807\/1560-7917.ES.2024.29.17.2400199","article-title":"Severe A(H1N1)pdm09 influenza acute encephalopathy outbreak in children in tuscany, Italy, December 2023 to January 2024","volume":"29","author":"Bartolini","year":"2024","journal-title":"Euro Surveill."},{"key":"B2","volume-title":"Influenza-Associated Pediatric Mortality Surveillance","year":""},{"key":"B3","volume-title":"Types of Influenza Viruses","year":""},{"key":"B4","doi-asserted-by":"publisher","first-page":"915","DOI":"10.1208\/s12248-012-9406-x","article-title":"Implementation of a reference-scaled average bioequivalence approach for highly variable generic drug products by the US food and drug administration","volume":"14","author":"Davit","year":"2012","journal-title":"AAPS J."},{"key":"B5","doi-asserted-by":"publisher","first-page":"2663","DOI":"10.1111\/bcp.13733","article-title":"Single- and multiple-dose pharmacokinetics and safety of pimodivir, a novel, non-nucleoside polymerase basic protein 2 subunit inhibitor of the influenza A virus polymerase complex, and interaction with oseltamivir: a phase 1 open-label study in healthy volunteers","volume":"84","author":"Deleu","year":"2018","journal-title":"Br. 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