ArticlePublished: 16 May 2026Xiaomo Wu ORCID: orcid.org/0000-0001-6515-15881,2,3,Jinying Zhong1 na1,Xiaorong He1 na1,Ming Wu4,Yu He1,Jiguang Wu5,Chunping Zhang1,Jinyan Zhang6,Meijun Guo7,Xiaochang Jiang8 &…Junyong Wong3,9 Gene Therapy (2026) Cite this articleSubjectsDrug deliveryGene therapyAbstractHemophilia A (HA), an X-linked bleeding disorder caused by factor VIII (FVIII) deficiency, is primarily managed with exogenous therapeutic agents; however, this treatment approach remains burdensome and fails to provide durable hemostatic control. Adeno-associated viral (AAV) vectors enabling endogenous FVIII expression have emerged as promising alternatives to address these limitations, but existing vectors show limited transduction efficiency and declining activity over time. Here, we report the development and preclinical evaluation of two bioengineered AAV8 vectors, HMR-001 and its codon-optimized variant HMR-001z, designed to enhance genome integrity, hepatocellular delivery, and translational efficiency. In hemophilia A mice, intravenous administration of HMR-001 induced dose-dependent and sustained FVIII expression, achieving substantial hemostatic improvement at the highest investigated dose (2 × 10¹³ vg/kg), with blood loss reduced to levels comparable to Xyntha prophylaxis. High-order triple-linkage ddPCR quantification revealed dose-dependent increases in full-length vector genome abundance, reaching 3.74, 21.55, and 48.52 copies per diploid genome at doses of 2 × 10¹², 8 × 10¹², and 2 × 10¹³ vg/kg, respectively. Building on these markedly improved genome delivery and preservation profiles, HMR-001z achieved complete hemostatic correction at a dose of 1 × 10¹³ vg/kg, exhibiting approximately 30-fold higher FVIII expression than HMR-001 and reaching ~400 IU/dL. Collectively, these findings demonstrate that genome-level optimization combined with codon-usage refinement synergistically enhances AAV8-mediated FVIII expression, establishing HMR-001z as a durable and translationally advanced gene therapy candidate for hemophilia A.This is a preview of subscription content, access via your institutionAccess optionsSubscribe to this journalReceive 6 print issues and online access269,00 € per yearonly 44,83 € per issueLearn moreBuy this articlePurchase on SpringerLinkInstant access to the full article PDF.39,95 €Prices may be subject to local taxes which are calculated during checkoutFig. 1: Production and systemic delivery of HMR-001 AAV vector.The alternative text for this image may have been generated using AI.Fig. 2: Circulating hFVIII antigen levels and hemostatic efficacy following intravenous administration of HMR-001.The alternative text for this image may have been generated using AI.Fig. 3: Hepatic transduction and hFVIII-SQ transcription revealed by RNA scope in situ hybridization.The alternative text for this image may have been generated using AI.Fig. 4: HMR-001 vector genome biodistribution.The alternative text for this image may have been generated using AI.Fig. 5: Analysis of transduced full-length HMR-001 vector genomes by linkage ddPCR assays.The alternative text for this image may have been generated using AI.Fig. 6: Enhanced hFVIII-SQ expression and complete hemostatic correction mediated by codon-optimized HMR-001z.The alternative text for this image may have been generated using AI.Data availabilityAll data associated with this study are available in the main text or the Supplementary Information data file. 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Mol Ther Methods Clin Dev. 2022;24:142–53.CAS PubMed Google Scholar Download referencesAcknowledgementsWe thank Francisco Bizouarn for providing valuable calibration support for data generated using a 4-plex ddPCR triple-linkage assay (QX600 Droplet Reader, Bio-Rad Laboratories). We also thank hematologist Hongyue Zhang for the thoughtful discussion. Xiaomo Wu acknowledges support from the Fuzhou Municipal Health Commission Young Talent Research Project (2022-S-rc4). Junyong Wong acknowledges support from the H.M. Hemophilia Foundation (S09F07). As a fee-for-service, animal studies and tissue processing were performed by GemPharmatech LLC, a contract research organization providing genetically engineered mouse models and phenotyping/functional assessments.Author informationAuthor notesThese authors contributed equally: Jinying Zhong, Xiaorong He.Authors and AffiliationsRegenerative Medicine and Gene Therapy Lab, Fuzhou Dermatology Hospital, Fuzhou, ChinaXiaomo Wu, Jinying Zhong, Xiaorong He, Yu He & Chunping ZhangDepartment of Biomedicine, University of Basel, Basel, SwitzerlandXiaomo WuHumvira Therapeutics, East Lake High-tech Campus, Wuhan, ChinaXiaomo Wu & Junyong WongThe United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Fuzhou, ChinaMing WuEngineering Research Centre of Fujian Modern Fermentation Technology, Fujian Normal University, Fuzhou, ChinaJiguang WuFujian Provincial Geriatric Hospital, Fuzhou, ChinaJinyan ZhangBaiChuangyi Biotechnology Inc., Shanghai, ChinaMeijun GuoUniversity of Toronto Scarborough, Toronto, ON, CanadaXiaochang JiangHelyxQuest Co. Ltd., Suzhou, ChinaJunyong WongAuthorsXiaomo WuView author publicationsSearch author on:PubMed Google ScholarJinying ZhongView author publicationsSearch author on:PubMed Google ScholarXiaorong HeView author publicationsSearch author on:PubMed Google ScholarMing WuView author publicationsSearch author on:PubMed Google ScholarYu HeView author publicationsSearch author on:PubMed Google ScholarJiguang WuView author publicationsSearch author on:PubMed Google ScholarChunping ZhangView author publicationsSearch author on:PubMed Google ScholarJinyan ZhangView author publicationsSearch author on:PubMed Google ScholarMeijun GuoView author publicationsSearch author on:PubMed Google ScholarXiaochang JiangView author publicationsSearch author on:PubMed Google ScholarJunyong WongView author publicationsSearch author on:PubMed Google ScholarContributionsXW designed and supervised the research and wrote the manuscript; XW, JZ, XH, and JWu analyzed the data; JZ, XH, MW, MG, JZhang, XJ, YH, and CZ conducted the molecular and biochemical experiments; XW and JW coordinated the project; all authors approved the final manuscript.Corresponding authorCorrespondence to Xiaomo Wu.Ethics declarationsCompeting interestsXW and JW have co-submitted a patent application concerning the methodology described in this study. XW has submitted a separate patent application related to methods applied in this study. XW and JW are scientific co-founders of Humvira Therapeutics and hold equity in this entity. The remaining authors declare no competing interests.Additional informationPublisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.Supplementary informationSupplementary Figures (download PDF )Rights and permissionsSpringer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.Reprints and permissionsAbout this article