RSVpreF

-- Positive Phase 2 (Australia) results strengthen potential best-in-class profile of RSV+hMPV±PIV3 combination vaccines, with the potential differentiated ability to re-vaccinate individuals previously receiving approved RSV vaccines to restore and broaden protection -- -- Robust neutralizing antibody responses across RSV, hMPV and PIV3 in Phase 2 recapitulates Phase 1 results demonstrating best-in-class breadth (with no immune interference) and no drop-off in responses in the oldest participants (75+ years) -- -- Favorable safety & tolerability profile and successful 2,000L commercial-scale production further de-risk late-stage development and commercialization -- SHANGHAI, Sept. 6, 2026 /PRNewswire/ -- Clover Biopharmaceuticals, Ltd. (Clover; HKEX: 02197), a global commercial-stage biotechnology company committed to unleashing the power of innovative vaccines to save lives and improve health around the world, today announced positive preliminary data from a Phase 2 clinical trial in older adults in Australia evaluating SCB-1022 (RSV + hMPV) and SCB-1033 (RSV + hMPV + PIV3) protein-based vaccine candidates based on prefusion-stabilized F (PreF)-Trimer subunit vaccine antigens utilizing Clover's validated Trimer-Tag vaccine technology platform. "We are pleased to announce positive Phase 2 clinical data strengthening the potential first-in-class and best-in-class profile for our RSV+hMPV±PIV3 combination vaccine candidates, with the potential differentiated ability to re-vaccinate individuals previously receiving approved RSV vaccines to restore and broaden protection," said Joshua Liang, Chief Executive Officer & Board Director of Clover. "The positive Phase 2 results significantly de-risk future late-stage development. Importantly, the results also continue to validate our differentiated Trimer-Tag platform for the development of multi-valent protein-based respiratory vaccines that have the potential to make an impact on public health and on chronic diseases caused by respiratory viruses[1]." The ongoing Phase 2 trial for Clover's combination vaccine candidates is a randomized, observer-blinded, multi-center study with 420 older adults (60-85 years) enrolled in Australia, and the participants have been randomized to receive either SCB-1022 (RSV + hMPV), SCB-1033 (RSV + hMPV + PIV3) or placebo. Immunogenicity Antibody titers (geometric mean titers [GMTs]) at 28 days post-vaccination in the Phase 2 were generally in-line with or trended higher than the prior Phase 1 trial. Geometric mean fold rises (GMFRs) in neutralizing antibodies (nAbs) at 28 days post-vaccination compared to pre-vaccination: RSV nAbs: Approximately 6-9 fold increases hMPV nAbs: Approximately 6-8 fold increases PIV3 nAbs: Greater than 3 fold increase (approximately 5 fold increase in participants with baseline PIV3 nAbs in the bottom tertile), driven by up to approximately 20 fold increases in PIV3 PreF-specific antibodies[2] No drop-off in antibody responses observed in the oldest participants (75+ years) compared to younger participants (60-74 years). No signs of immune interference on RSV and hMPV nAbs from the addition of PIV3 PreF antigen in SCB-1033 (RSV+hMPV+PIV3) compared to SCB-1022 (RSV+hMPV). Respiratory Tract Infections (Based on AE Reporting) Approximately 62% lower rate of respiratory tract infection was observed in the vaccine groups (SCB-1022 and SCB-1033) versus the placebo group within 28 days of vaccination based on AE reporting of any respiratory tract infections (no PCR sequencing of infection cases was conducted in the study). Significant RSV outbreak[3] with co-circulation[4] of hMPV and PIV in Australia occurred during the study enrollment and follow-up period. Safety and Reactogenicity SCB-1022 and SCB-1033 were generally well-tolerated; solicited local and systemic adverse events (AEs) within 7 days of vaccination were mostly mild and all transient. The most common solicited AEs were fatigue, headache and injection site pain, with mean durations of approximately 2 days for the vaccine groups (SCB-1022 and SCB-1033) and the placebo group. The frequency of unsolicited AEs within 28 days of vaccination was similar across the vaccine and placebo groups. There were no vaccine-related serious adverse events (SAEs), AEs of special interest (AESIs), or AEs leading to discontinuation. Commercial-Scale Manufacturing Scale-Up In parallel with the Phase 2 trial, Clover conducted commercial-scale 2,000L bioreactor scale-up production of multiple batches of Trimer-Tagged RSV, hMPV and PIV3 PreF antigen components of SCB-1022/1033. The successful 2,000L production process scale-up further de-risk future late-stage development and commercialization. Based on these positive Phase 2 results for the RSV + hMPV ± PIV3 combination vaccine candidates further validating the Trimer-Tag platform, Clover will continue to evaluate continued mid- and late-stage development plans as well as potential global collaboration opportunities for value maximization. About Clover Clover Biopharmaceuticals is a global commercial-stage biotechnology company committed to unleashing the power of innovative vaccines to save lives and improve health around the world. With integrated research and development, manufacturing and commercial capabilities as well as strong partnerships with organizations globally, Clover has a diverse pipeline of candidates that have the potential to meaningfully reduce the burden of vaccine-preventable diseases—and to make more diseases preventable.  Clover Forward-looking Statements This press release contains certain forward-looking statements and information relating to us and our subsidiaries that are based on the beliefs of our management as well as assumptions made by and information currently available to our management. When used, the words "aim," "anticipate," "believe," "could," "estimate," "expect," "going forward," "intend," "may," "might," "ought to," "plan," "potential," "predict," "project," "seek," "should," "will," "would" and the negative of these words and other similar expressions, as they relate to us or our management, are intended to identify forward-looking statements. Forward-looking statements are based on our current expectations and assumptions regarding our business, the economy and other future conditions. We give no assurance that these expectations and assumptions will prove to have been correct. Because forward-looking statements relate to the future, they are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict. Our results may differ materially from those contemplated by the forward-looking statements. They are neither statements of historical fact nor guarantees or assurances of future performance. We caution you therefore against placing undue reliance on any of these forward-looking statements. Any forward-looking statement made by us in this document speaks only as of the date on which it is made. Factors or events that could cause our actual results to differ may emerge from time to time. SOURCE Clover Biopharma 21% more press release views with Request a Demo

呼吸道合胞病毒（RSV）是一种广泛存在的呼吸道病原体，也是导致婴幼儿、老年人及免疫功能低下人群呼吸道感染的重要原因之一。RSV感染可引起从轻度上呼吸道感染到严重下呼吸道疾病的不同临床表现，其中婴幼儿可能发生毛细支气管炎和肺炎，老年人及慢性疾病患者则面临更高的重症和住院风险。中国作为RSV感染负担较高的国家之一，婴幼儿RSV相关急性下呼吸道感染病例数量庞大，同时老年人群和高风险患者也受到持续影响。 长期以来，RSV缺乏有效的特异性预防手段。近年来，随着mRNA技术、重组蛋白疫苗技术以及单克隆抗体技术的发展，RSV预防领域取得重要突破。本文将围绕RSV感染预防领域的最新进展，系统介绍当前主要RSV疫苗和抗体疗法的技术路线、作用机制、免疫效果及安全性特点，并探讨未来RSV防控策略的发展方向。随着创新疫苗和抗体药物不断推进，RSV感染有望从“难以预防”逐步迈向“精准防控”的新时代。 RSV结构、感染机制和流行特点 RSV是一种具有囊膜的非分节段负链RNA病毒，属于副黏病毒科肺病毒属。根据抗原特征，RSV主要分为A型（RSV-A）和B型（RSV-B）两个亚型，两者均可在全球范围内流行，并导致相似程度的疾病负担。RSV感染后的免疫保护时间较短，人体自然感染后通常无法形成长期有效免疫，这也是RSV易发生重复感染的重要原因。 RSV病毒颗粒包含多种结构蛋白，其中融合蛋白（F蛋白）和附着蛋白（G蛋白）在病毒感染过程中发挥核心作用。G蛋白负责介导病毒与宿主细胞结合，而F蛋白则促进病毒囊膜与宿主细胞膜融合，使病毒进入细胞。目前，多数RSV中和抗体主要靶向F蛋白，尤其是融合前构象F蛋白，这也成为当前RSV疫苗和单克隆抗体研发的重要靶点。 此外，RSV还具有较强的免疫逃逸能力。病毒编码的NS1和NS2等非结构蛋白能够抑制干扰素信号通路、影响树突状细胞成熟，并调节宿主炎症反应，从而帮助病毒逃避免疫系统识别。F蛋白也可通过影响IFN-λ等抗病毒免疫因子的产生，促进病毒复制和持续感染。 RSV主要通过呼吸道飞沫以及接触污染表面传播。病毒首先侵入鼻咽部和结膜黏膜，感染上呼吸道上皮细胞，随后进一步扩散至下呼吸道，感染纤毛气道上皮细胞。随着病毒复制增加，感染细胞脱落并导致细支气管阻塞，引发中性粒细胞浸润、水肿以及炎症反应，最终造成气道损伤。 婴幼儿是RSV感染最主要的高风险人群，典型表现为毛细支气管炎。患儿通常先出现类似感冒的症状，如流鼻涕、咳嗽和发热，随后可能发展为呼吸急促、喘鸣、呼吸困难甚至肺炎。对于老年人及慢性疾病患者，RSV感染同样可能诱发严重下呼吸道疾病，并增加住院和死亡风险。 全球范围内，RSV每年可导致约3300万例下呼吸道感染病例，其中约300万例需要住院治疗。中国是全球RSV疾病负担较高的国家之一，研究显示，RSV是导致中国5岁以下儿童急性下呼吸道感染的重要病原，每年造成大量儿童门急诊就诊和住院病例。同时，随着人口老龄化加剧，老年人群RSV相关疾病负担也日益受到关注。 RSV单克隆抗体开启精准免疫防护新时代 目前，RSV感染的治疗策略主要包括支持治疗、免疫预防和抗病毒治疗三大方向。由于大多数RSV感染病例，尤其是轻中度儿童感染，并不需要特异性药物干预，临床治疗仍以缓解症状和维持生命支持为主，包括鼻腔分泌物清理、退热、补液以及氧疗等措施。对于出现严重呼吸困难或呼吸衰竭的患者，则可能需要高流量鼻导管吸氧（HFNC）、持续气道正压通气（CPAP）或机械通气等支持治疗。 在抗病毒治疗方面，目前可选择药物仍较为有限。利巴韦林（Ribavirin）是一种核苷类似物，曾被用于RSV治疗，但由于其疗效证据有限，同时存在成本较高、给药安全性以及潜在不良反应等问题，目前并不推荐常规使用。此外，针对RSV融合蛋白的小分子抑制剂齐雷索韦（Ziresovir）正在开展临床研究，早期结果显示其能够改善RSV感染婴幼儿的毛细支气管炎症状，为未来RSV治疗提供了新的方向。 相比传统抗病毒药物，靶向RSV关键抗原的单克隆抗体（mAbs）已成为近年来RSV预防领域的重要突破。由于RSV自然感染难以诱导长期保护性免疫，直接给予具有中和活性的抗体，可在病毒暴露前提供快速、精准的被动免疫保护。目前，RSV单抗主要靶点均集中于RSV融合前F蛋白。 尼塞韦单抗（Nirsevimab，Beyfortus®）是目前应用最广泛的长效RSV单克隆抗体之一，由赛诺菲与阿斯利康联合开发，并已于2023年获得中国国家药品监督管理局（NMPA）批准，用于预防新生儿和婴儿RSV相关下呼吸道感染。该抗体通过结合RSV F蛋白融合前构象中的保守表位，阻断病毒与宿主细胞融合。尼塞韦单抗具有更长血清半衰期，仅需单次肌肉注射即可覆盖整个RSV流行季。在Ⅲ期研究中，尼塞韦单抗可显著降低婴幼儿RSV相关下呼吸道感染发生率，并表现出良好的安全性。 另一款长效RSV单抗克莱罗韦单抗（Clesrovimab，Enflonsia®）由默沙东开发，于2025年6月美国获批、2026年6月中国获批。该抗体靶向RSV F蛋白Ⅳ位点，对RSV-A和RSV-B均具有广泛中和活性，采用固定剂量给药策略，可为婴幼儿提供最长约5个月的保护。目前，该产品也正在全球范围内推进商业化布局。 除已上市产品外，中国企业也积极布局RSV单克隆抗体研发，推动国产RSV预防产品的发展。目前，国内已有多个抗RSV单抗项目进入临床后期或注册申请阶段，其中珠海泰诺麦博自主研发的全球首款一针给药拥有长达9个月保护数据的全人源单克隆抗体新药——新多妥（通用名：芮特韦拜单抗注射液，曾用名：TNM001注射液）已获得NMPA批准上市： 部分国内RSV单克隆抗体产品，数据来源：智慧芽（2026.8） mRNA与重组蛋白技术推动下一代RSV疫苗研发加速 长期以来，RSV疫苗研发受到病毒免疫逃逸机制复杂、自然感染后免疫保护持续时间有限以及早期疫苗相关增强型疾病（VAERD）风险等因素影响，开发过程面临较大挑战。近年来，随着结构生物学、基因工程和新型疫苗递送技术的发展，RSV疫苗研发取得重要突破。目前，全球RSV疫苗主要涵盖mRNA疫苗、重组蛋白亚单位疫苗、病毒载体疫苗以及减毒活疫苗等技术路线。其中，基于RSV融合前构象F蛋白（prefusion F protein）的重组亚单位疫苗，以及利用核酸递送技术的mRNA疫苗，已成为当前临床开发最活跃的两大方向。 mRNA疫苗通过人工合成编码RSV F蛋白的信使RNA，并利用脂质纳米颗粒（LNP）等递送系统将其导入宿主细胞，在细胞内完成抗原蛋白表达，从而同时激活体液免疫和细胞免疫反应，诱导产生中和抗体以及CD4⁺、CD8⁺ T细胞应答。该技术具有研发周期短、抗原设计灵活以及易于针对病毒变异进行快速优化等优势。新冠病毒mRNA疫苗的成功商业化进一步推动了RSV mRNA疫苗的发展。目前，Moderna的mRESVIA已成为全球首款获批上市的RSV mRNA疫苗，用于老年人群RSV相关下呼吸道疾病（RSV-LRTD）的预防。临床研究显示，该疫苗能够诱导较强的中和抗体反应和T细胞免疫，并表现出良好的保护效果。然而，mRNA疫苗仍面临生产成本、冷链储存条件以及接种后短期免疫反应等挑战，例如注射部位疼痛、疲劳和发热等。 重组蛋白亚单位疫苗是目前RSV疫苗研发中最成熟的技术路线之一。该类疫苗通常采用哺乳动物细胞表达系统（如CHO细胞）生产稳定化的RSV融合前F蛋白，通过基因工程构建表达载体，经细胞培养、蛋白表达、纯化以及结构稳定化处理后获得高纯度抗原。由于融合前F蛋白包含大量关键中和抗体结合表位，能够诱导更强的保护性免疫，因此成为目前RSV疫苗设计的核心抗原。相比传统灭活疫苗或全病毒疫苗，重组亚单位疫苗具有抗原组成明确、安全性高、生产工艺成熟以及质量控制体系完善等优势，但由于其诱导细胞免疫能力相对有限，通常需要结合佐剂增强免疫原性。 目前，辉瑞的Abrysvo和葛兰素史克的Arexvy是全球已上市的代表性RSV重组蛋白疫苗，均基于稳定化融合前F蛋白设计，并在老年人群中显示出较高的保护效力。其中，Abrysvo还被用于孕妇免疫，通过母体抗体转移为出生后早期婴儿提供被动免疫保护。此外，随着RSV疫苗产业化推进，基于CHO细胞表达体系的重组蛋白生产工艺也逐渐成为未来RSV疫苗商业化制造的重要技术路径。 除mRNA疫苗和重组蛋白疫苗外，病毒载体疫苗和减毒活疫苗仍处于持续探索阶段。病毒载体疫苗利用腺病毒、痘苗病毒等递送RSV抗原，可诱导较强的细胞免疫和长期免疫记忆，但其效果可能受到机体预存抗载体免疫影响。减毒活疫苗则主要面向婴幼儿人群，通过降低病毒复制能力，在保持免疫原性的同时提升安全性，目前仍处于临床研究阶段。 近年来，中国RSV疫苗研发也快速推进，多种技术路线已进入临床阶段。其中，重组蛋白亚单位疫苗进展较为领先。成都迈科康生物科技股份有限公司开发的重组呼吸道合胞病毒疫苗（CHO细胞）已进入临床Ⅲ期，是目前国内研发进度较快的RSV疫苗项目之一；北京百邑无忧科技发展有限公司开发的BW-201（Adj1）预防性疫苗也已推进至临床Ⅲ期阶段。这些产品均采用重组抗原技术路线，旨在通过稳定化RSV关键抗原诱导有效免疫保护，代表了中国企业在RSV疫苗领域的重要突破。 与此同时，中国RSV mRNA疫苗研发也快速发展，多家企业已推进相关产品进入临床阶段。苏州艾博生物、深圳深信生物等企业的RSV mRNA疫苗已进入临床Ⅱ期研究阶段，部分产品采用单价或二价抗原设计策略，探索通过核酸技术实现更强、更广谱的免疫保护。此外，石药集团巨石生物等企业也开展了RSV mRNA疫苗早期临床研究，进一步丰富了国内RSV疫苗研发管线。 部分开发中的RSV疫苗产品，数据来源：智慧芽（2026.8） 总体来看，不同RSV疫苗平台具有互补优势：mRNA疫苗具有开发速度快、免疫激活能力强以及适应病毒变化能力强等特点；重组蛋白疫苗则凭借成熟生产工艺、高安全性和良好的产业化基础，更适用于老年人、孕妇等重点人群；病毒载体疫苗则在诱导长期细胞免疫方面具有潜力。未来，RSV疫苗研发将进一步向广谱保护、多价联合疫苗、个体化免疫策略以及更加灵活高效的生产体系方向发展。 总结：RSV预防体系加速构建，中国研发力量推动创新突破 RSV感染已成为全球重要公共卫生挑战，尤其威胁婴幼儿、老年人及免疫功能低下人群。目前，由于缺乏高效特异性治疗手段，疫苗和单克隆抗体已成为降低RSV疾病负担的核心策略。近年来，随着结构生物学、mRNA技术和重组蛋白表达工艺的发展，RSV预防领域取得快速突破，全球多个疫苗和抗体产品相继进入临床及商业化阶段。 中国RSV疫苗与抗体研发也进入快速发展阶段，已形成覆盖mRNA疫苗、重组亚单位疫苗及单克隆抗体等多技术路线的创新格局。其中，部分国产RSV疫苗已进入临床Ⅲ期阶段，体现出中国在该领域的研发实力和产业化潜力。未来，随着更多创新产品推进临床验证及商业转化，中国有望在全球RSV预防体系建设中发挥更加重要的作用。通过疫苗接种、长效抗体预防以及个体化免疫策略的结合，有望进一步降低RSV相关疾病负担，提升高风险人群的健康保障水平。 多宁生物依托覆盖上游细胞培养、一次性生物反应器、下游过滤纯化、流体管理及质量控制等环节的一站式生物工艺解决方案，为RSV单克隆抗体、重组蛋白疫苗、mRNA疫苗等创新产品开发提供全流程支持。针对RSV单克隆抗体，多宁生物可提供从哺乳动物细胞培养、纯化工艺优化到制剂开发的综合支持，助力提高抗体产量、纯度及工艺稳定性。针对重组亚单位疫苗，多宁生物基于CHO细胞培养基平台、生物反应器系统及下游纯化技术，可支持RSV融合前F蛋白等关键抗原的规模化生产与工艺放大。同时，针对mRNA疫苗研发需求，多宁生物可提供涵盖质粒制备、体外转录、核酸纯化、LNP制备及分析检测等环节的工艺支持，帮助客户提升研发效率和产业化能力。 未来，多宁生物将持续依托完善的一站式生物工艺平台，助力全球RSV预防产品创新，加速新一代疫苗与抗体疗法从研发阶段迈向规模化制造，为呼吸道病毒感染防控提供更加高效、可靠的生物制造解决方案。 无血清、化学限定CHO细胞培养基 多宁生物无血清CHO细胞培养基平台专为重组蛋白、抗体及新型疫苗等生物制品的研发与生产打造，涵盖种子扩增、补料分批培养、灌流培养及流加培养等多种工艺场景。培养基采用无动物源成分、完全化学成分限定配方设计，可有效降低批次差异和污染风险。平台适配多种主流CHO细胞株及不同筛选系统，支持高密度悬浮培养和高水平蛋白表达。产品按照GMP标准生产，具有良好的工艺适配性和放大性能，为工艺开发和规模化生产提供稳定可靠的培养基解决方案。 DuoBioX® Explore 系列平行生物反应器系统 DuoBioX® Explore提供500 mL至15 L多种台式反应器罐体规格，满足工艺开发、优化和表征需求，可高效支持重组蛋白及新型疫苗开发。系统支持1至8台罐体平行控制，可高效开展培养条件筛选和工艺研究。基于WinCC工业级架构开发的软件平台具备强大的自动化控制能力，可精准调控DO、pH、温度及通气策略，支持高密度CHO等哺乳动物细胞培养和灌流工艺开发，为疫苗抗原的高效表达和工艺放大提供可靠支撑。 DuoBioX® Pro系列 一次性生物反应器 DuoBioX® Pro一次性生物反应器采用底部搅拌式设计，可实现50 L至2000 L规模的线性工艺放大，广泛应用于生物制药的中试放大及GMP生产。系统搭配多宁自主研发的3D一次性细胞培养袋，具有优异的生物相容性以及极低的溶出和析出水平，有助于保障产品安全性与工艺稳定性。独特的搅拌与通气一体化设计在降低剪切力的同时实现高效传质和混合，特别适用于CHO等哺乳动物细胞培养。基于西门子PLC和WinCC控制平台，系统支持精准过程控制与数据追溯，为生物制品和新型疫苗生产提供可靠保障。 参考文献： D.Genis, W.Riaz, A.Hussain, et al., Current and Emerging Strategies for the Prevention of Respiratory Syncytial Virus (RSV) Infections: A Comprehensive Review of Vaccines and Antibody Therapies. Cureus, 2026. W.Xu, R.H.Katte, M.Lu, RSV vaccine development: advances and fusion protein-focused strategies. Front. Immunol.,2026. D.Trusinskaa, B.Leeb, S. Ferdous, et al., Real-world evidence on RSV vaccine uptake, effectiveness, and safety in older adults: a systematic review and meta-analysis. The Lancet Regional Health Europe, 2026. S.Lee, J.Yoon, S.Shoote, et al. Respiratory syncytial virus mRNA vaccine-induced immunity and protection against subgroups A and B in mice. ImmunoHorizons, 2026. 关于多宁生物 上海多宁生物科技股份有限公司是一家中国领先的一站式生物工艺解决方案提供商，致力于提供生物制药产品从研发到商业化生产的综合解决方案，包括试剂及耗材、仪器设备、服务。公司主要运营生物工艺解决方案、实验室产品及服务两大业务线，通过一站式生物工艺体系帮助合作伙伴实现高效、稳定、质量及成本可控的药物研发及生产流程。 了解更多：www.duoningbio.com 媒体垂询：PR@duoningbio.com Respiratory syncytial virus (RSV) is a widely prevalent respiratory pathogen and one of the major causes of respiratory infections among infants, older adults, and immunocompromised populations. RSV infection can lead to a broad spectrum of clinical manifestations, ranging from mild upper respiratory tract infections to severe lower respiratory tract diseases. In infants, RSV infection may cause bronchiolitis and pneumonia, while older adults and patients with chronic diseases face higher risks of severe disease and hospitalization. As one of the countries with a substantial RSV disease burden, China experiences a large number of RSV-associated acute lower respiratory tract infections among infants, while elderly populations and high-risk individuals continue to be significantly affected. For many years, effective specific preventive measures against RSV have been lacking. In recent years, significant breakthroughs have been achieved in RSV prevention with the advancement of mRNA technology, recombinant protein vaccine technology, and monoclonal antibody technology. This article provides a comprehensive overview of the latest developments in RSV infection prevention, systematically introducing the current major RSV vaccine and antibody therapy approaches, their mechanisms of action, immune efficacy, and safety profiles, while discussing future directions for RSV prevention and control strategies. With the continued advancement of innovative vaccines and antibody therapeutics, RSV infection is expected to transition from a disease that is "difficult to prevent" toward a new era of "precision prevention and control." RSV Structure, Infection Mechanisms, and Epidemiological Characteristics RSV is an enveloped, non-segmented negative-sense RNA virus belonging to the genus Orthopneumovirus within the family Pneumoviridae. Based on antigenic characteristics, RSV is mainly classified into two subtypes: RSV-A and RSV-B. Both subtypes circulate globally and contribute to a similar disease burden. Immune protection following RSV infection is relatively short-lived, and natural infection generally does not induce long-lasting effective immunity, which is a major reason why repeated RSV infections are common. RSV virions contain multiple structural proteins, among which the fusion protein (F protein) and attachment protein (G protein) play essential roles in virus infection. The G protein mediates virus attachment to host cells, while the F protein facilitates fusion between the virus envelope and the host cell membrane, allowing virus entry into cells. Currently, most RSV-neutralizing antibodies target the F protein, particularly the prefusion conformation of the F protein, which has become a key target for RSV vaccine and monoclonal antibody development. In addition, RSV possesses strong immune evasion capabilities. Virus nonstructural proteins such as NS1 and NS2 can suppress interferon signaling pathways, affect dendritic cell maturation, and regulate host inflammatory responses, thereby helping the virus evade immune recognition. The F protein may also promote virus replication and persistent infection by influencing the production of antivirus immune factors such as IFN-λ. RSV is primarily transmitted through respiratory droplets and contact with contaminated surfaces. The virus initially infects the nasopharyngeal and conjunctival mucosal surfaces, targeting upper respiratory epithelial cells, and subsequently spreads to the lower respiratory tract where it infects ciliated airway epithelial cells. As virus replication increases, infected cells detach and contribute to bronchiolar obstruction, triggering neutrophil infiltration, edema, and inflammatory responses, ultimately resulting in airway damage. Infants represent the primary high-risk population for RSV infection, with bronchiolitis being the typical clinical manifestation. Children usually initially develop cold-like symptoms, including runny nose, cough, and fever, which may progress to rapid breathing, wheezing, respiratory distress, and even pneumonia. For older adults and patients with chronic diseases, RSV infection can also induce severe lower respiratory tract disease and increase the risks of hospitalization and mortality. Globally, RSV causes approximately 33 million cases of lower respiratory tract infections each year, with around 3 million cases requiring hospitalization. China is among the countries with a high RSV disease burden worldwide. Studies have shown that RSV is an important pathogen responsible for acute lower respiratory tract infections in children under five years of age in China, resulting in a large number of outpatient visits and hospitalizations annually. Meanwhile, with the acceleration of population aging, the burden of RSV-associated diseases among elderly populations has received increasing attention. RSV Monoclonal Antibodies Open a New Era of Precision Immune Protection Currently, treatment strategies for RSV infection mainly include three major approaches: supportive care, immune prevention, and antivirus therapy. Since most RSV infection cases, particularly mild-to-moderate infections in children, do not require specific drug intervention, clinical management remains primarily focused on symptom relief and life-support measures, including nasal secretion clearance, fever reduction, fluid supplementation, and oxygen therapy. For patients with severe respiratory distress or respiratory failure, supportive treatments such as high-flow nasal cannula (HFNC) oxygen therapy, continuous positive airway pressure (CPAP), or mechanical ventilation may be required. In terms of antivirus therapy, available treatment options remain relatively limited. Ribavirin, a nucleoside analogue, was previously used for RSV treatment; however, due to limited evidence supporting its efficacy, along with concerns related to high cost, administration safety, and potential adverse effects, routine use is currently not recommended. In addition, the small-molecule RSV fusion protein inhibitor ziresovir is undergoing clinical studies. Early results have shown that it may improve bronchiolitis symptoms in infants infected with RSV, providing a new direction for future RSV treatment. Compared with traditional antivirus drugs, monoclonal antibodies (mAbs) targeting key RSV antigens have become an important breakthrough in RSV prevention in recent years. Since natural RSV infection is unable to induce long-lasting protective immunity, direct administration of antibodies with neutralizing activity can provide rapid and precise passive immune protection before virus exposure. Currently, the primary targets of RSV monoclonal antibodies are concentrated on the RSV prefusion F protein. Nirsevimab (Beyfortus®) is currently one of the most widely used long-acting RSV monoclonal antibodies. It was jointly developed by Sanofi and AstraZeneca and received approval from the National Medical Products Administration (NMPA) of China in 2023 for the prevention of RSV-associated lower respiratory tract infections in newborns and infants. The antibody binds to a conserved epitope within the prefusion conformation of the RSV F protein, thereby blocking virus fusion with host cells. Nirsevimab has an extended serum half-life and can provide protection throughout the entire RSV season with a single intramuscular injection. In Phase III clinical studies, nirsevimab significantly reduced the incidence of RSV-associated lower respiratory tract infections in infants and demonstrated a favorable safety profile. Another long-acting RSV monoclonal antibody, clesrovimab (Enflonsia®), was developed by Merck and was approved in the United States in June 2025 and in China in June 2026. This antibody targets site IV of the RSV F protein and exhibits broad neutralizing activity against both RSV-A and RSV-B. Using a fixed-dose administration strategy, clesrovimab can provide infants with protection for up to approximately five months. The product is also advancing commercialization efforts globally. In addition to marketed products, Chinese companies are actively investing in RSV monoclonal antibody development to promote the advancement of domestic RSV prevention products. Currently, multiple anti-RSV monoclonal antibody programs in China have entered late-stage clinical development or regulatory submission stages. mRNA and Recombinant Protein Technologies Accelerate the Development of Next-generation RSV Vaccines For many years, RSV vaccine development has faced significant challenges due to complex virus immune evasion mechanisms, limited duration of immune protection following natural infection, and the risk of vaccine-associated enhanced respiratory disease (VAERD) observed in early vaccine studies. In recent years, with advances in structural biology, genetic engineering, and novel vaccine delivery technologies, major breakthroughs have been achieved in RSV vaccine development. Currently, global RSV vaccines mainly encompass several technological approaches, including mRNA vaccines, recombinant protein subunit vaccines, virus vector vaccines, and live attenuated vaccines. Among these, recombinant subunit vaccines based on the prefusion conformation of the RSV fusion protein (prefusion F protein), as well as mRNA vaccines utilizing nucleic acid delivery technologies, have become the two most active areas in current clinical development. mRNA vaccines use artificially synthesized messenger RNA encoding the RSV F protein and deliver it into host cells through delivery systems such as lipid nanoparticles (LNPs), enabling antigen protein expression within cells. This approach activates both humoral and cellular immune responses, inducing neutralizing antibodies as well as CD4⁺ and CD8⁺ T-cell responses. This technology offers advantages including short development cycles, flexible antigen design, and the ability to rapidly optimize vaccine formulations in response to virus mutations. The successful commercialization of COVID-19 mRNA vaccines has further accelerated the development of RSV mRNA vaccines. Currently, Moderna’s mRESVIA has become the world’s first approved RSV mRNA vaccine, indicated for the prevention of RSV-associated lower respiratory tract disease (RSV-LRTD) in older adults. Clinical studies have demonstrated that this vaccine can induce strong neutralizing antibody responses and T-cell immunity, while showing favorable protective efficacy. However, mRNA vaccines still face challenges related to manufacturing costs, cold-chain storage requirements, and short-term immune reactions following vaccination, such as injection-site pain, fatigue, and fever. Recombinant protein subunit vaccines represent one of the most mature technological approaches in current RSV vaccine development. These vaccines typically utilize mammalian cell expression systems (such as CHO cells) to produce stabilized prefusion RSV F protein. Through genetic engineering-based expression vector construction, cell culture, protein expression, purification, and structural stabilization processes, highly purified antigens are obtained. Since prefusion F protein contains multiple critical neutralizing antibody epitopes and can induce stronger protective immune responses, it has become the core antigen design strategy for current RSV vaccines. Compared with traditional inactivated vaccines or whole-virus vaccines, recombinant subunit vaccines offer advantages including well-defined antigen composition, high safety, mature manufacturing processes, and established quality control systems. However, because their ability to induce cellular immune responses is relatively limited, they typically require combination with adjuvants to enhance immunogenicity. Currently, Pfizer's Abrysvo and GSK's Arexvy are representative recombinant protein RSV vaccines that have been approved globally. Both are based on stabilized prefusion F protein designs and have demonstrated high protective efficacy in older adults. Among them, Abrysvo is also used for maternal immunization, providing passive immune protection to newborns during early life through the transfer of maternal antibodies. In addition, with the advancement of RSV vaccine commercialization, recombinant protein production platforms based on CHO cell expression systems are gradually becoming an important manufacturing pathway for future commercial-scale RSV vaccine production. In addition to mRNA and recombinant protein vaccines, virus vector vaccines and live attenuated vaccines remain under continued exploration. Virus vector vaccines utilize delivery platforms such as adenoviruses and vaccinia viruses to present RSV antigens, inducing strong cellular immune responses and long-term immune memory. However, their effectiveness may be affected by pre-existing immunity against the virus vector. Live attenuated vaccines are primarily designed for infants and reduce virus replication capacity to improve safety while maintaining immunogenicity. These vaccines remain under clinical investigation. In recent years, RSV vaccine development in China has also progressed rapidly, with multiple technological approaches entering clinical development stages. Among them, recombinant protein subunit vaccines have advanced relatively quickly. The recombinant respiratory syncytial virus vaccine (CHO cell) developed by Maxvax Biotechnology has entered Phase III clinical trials and represents one of the most advanced domestic RSV vaccine programs in China. The BW-201 (Adj1) preventive vaccine developed by BeneWill Technology has also progressed into Phase III clinical development. These products both adopt recombinant antigen technology approaches and aim to induce effective immune protection by stabilizing key RSV antigens, representing important breakthroughs by Chinese companies in the RSV vaccine field. Meanwhile, the development of RSV mRNA vaccines in China is also advancing rapidly, with multiple companies progressing related products into clinical studies. RSV mRNA vaccines developed by companies such as Abogen Biosciences and Innorna have entered Phase II clinical studies. Some products utilize monovalent or bivalent antigen design strategies to explore the potential of nucleic acid technologies in achieving stronger and broader immune protection. In addition, companies such as CSPC have also initiated early-stage clinical studies of RSV mRNA vaccines, further enriching the domestic RSV vaccine development pipeline. Overall, different RSV vaccine platforms offer complementary advantages: mRNA vaccines feature rapid development, strong immune activation capability, and high adaptability to virus changes; recombinant protein vaccines, with their mature manufacturing processes, high safety profiles, and strong industrialization foundation, are more suitable for key populations such as older adults and pregnant women; virus vector vaccines show potential in inducing long-lasting cellular immunity. In the future, RSV vaccine development will continue to advance toward broader protection, multivalent combination vaccines, personalized immunization strategies, and more flexible and efficient manufacturing systems. Conclusion RSV infection has become an important global public health challenge, particularly threatening infants, older adults, and immunocompromised populations. Currently, due to the lack of highly effective specific treatment options, vaccines and monoclonal antibodies have become core strategies for reducing the burden of RSV disease. In recent years, with advances in structural biology, mRNA technology, and recombinant protein expression processes, significant progress has been achieved in RSV prevention, with multiple vaccine and antibody products entering clinical development and commercialization stages worldwide. The development of RSV vaccines and antibody therapies in China has also entered a phase of rapid growth, forming an innovative landscape covering multiple technological approaches, including mRNA vaccines, recombinant subunit vaccines, and monoclonal antibodies. Among them, several domestic RSV vaccine candidates have entered Phase III clinical trials, demonstrating China's research capabilities and industrialization potential in this field. In the future, as more innovative products advance through clinical validation and commercial translation, China is expected to play an increasingly important role in the global RSV prevention landscape. Through the combination of vaccination, long-acting antibody prophylaxis, and personalized immune strategies, the burden of RSV-related diseases can be further reduced, while improving health protection for high-risk populations. Duoning Biotech leverages its one-stop bioprocessing solutions covering upstream cell culture, single-use bioreactors, downstream filtration and purification, fluid management, and quality control to provide comprehensive support for the development of innovative products such as RSV monoclonal antibodies, recombinant protein vaccines, and mRNA vaccines. For RSV monoclonal antibodies, we provide integrated support ranging from mammalian cell culture and purification process optimization to formulation development, helping improve antibody yield, purity, and process robustness. For recombinant subunit vaccines, our CHO cell culture media platform, bioreactor systems, and downstream purification technologies support the scalable production and process development of key antigens such as RSV prefusion F protein. Meanwhile, for mRNA vaccine development, we provide process support covering plasmid preparation, in vitro transcription, nucleic acid purification, LNP formulation, and analytical testing, helping customers improve development efficiency and commercialization capabilities. In the future, we will continue leveraging its comprehensive one-stop bioprocessing platform to support innovation in global RSV prevention products, accelerate the transition of next-generation vaccines and antibody therapies from research and development to large-scale manufacturing, and provide more efficient and reliable biomanufacturing solutions for respiratory virus infection prevention and control. Serum-Free, Chemically Defined CHO Cell Culture Media Our serum-free CHO cell culture media platform is specifically designed for the development and manufacturing of biopharmaceutical products, including recombinant proteins, antibodies, and novel vaccines. The platform covers various process scenarios such as seed expansion, fed-batch culture, perfusion culture, and intensified fed-batch cultivation. The media are formulated with animal-origin-free components and a fully chemically defined formulation, effectively reducing batch-to-batch variation and contamination risks. The platform is compatible with multiple mainstream CHO cell lines and different selection systems, enabling high-density suspension culture and high-level protein expression. Manufactured according to GMP standards, the products feature excellent process compatibility and scalability, providing stable and reliable media solutions for process development and large-scale production. DuoBioX® Explore Series Multi-Parallel Benchtop Bioreactor System DuoBioX® Explore offers a range of benchtop bioreactor vessels from 500 mL to 15 L, meeting the needs of process development, optimization, and characterization, and efficiently supporting the development of recombinant proteins and novel vaccines. The system enables parallel control of 1 to 8 vessels, facilitating efficient screening of culture conditions and process studies. The software platform, developed based on the industrial-grade WinCC architecture, provides powerful automated control capabilities, enabling precise regulation of DO, pH, temperature, and gas supply strategies. It supports high-density mammalian cell culture, as well as perfusion process development, providing reliable support for efficient vaccine antigen expression and process scale-up. DuoBioX® Pro Single-Use Bioreactor DuoBioX® Pro single-use bioreactors adopt a bottom-mounted stirring design, enabling linear process scale-up from 50 L to 2,000 L and are widely applied in pilot-scale production and GMP manufacturing of biopharmaceutical products. Equipped with Duoning's proprietary 3D single-use cell culture bags, the system offers excellent biocompatibility and extremely low levels of extractables and leachables, helping ensure product safety and process stability. The unique integrated stirring and aeration design achieves efficient mass transfer and mixing while minimizing shear stress, making it particularly suitable for mammalian cell culture such as CHO cell cultivation. Based on Siemens PLC and WinCC control platforms, the system supports precise process control and data traceability, providing reliable assurance for the production of biopharmaceutical products and novel vaccines. References: D.Genis, W.Riaz, A.Hussain, et al., Current and Emerging Strategies for the Prevention of Respiratory Syncytial Virus (RSV) Infections: A Comprehensive Review of Vaccines and Antibody Therapies. Cureus, 2026. W.Xu, R.H.Katte, M.Lu, RSV vaccine development: advances and fusion protein-focused strategies. Front. Immunol.,2026. D.Trusinskaa, B.Leeb, S. Ferdous, et al., Real-world evidence on RSV vaccine uptake, effectiveness, and safety in older adults: a systematic review and meta-analysis. The Lancet Regional Health Europe, 2026. S.Lee, J.Yoon, S.Shoote, et al. Respiratory syncytial virus mRNA vaccine-induced immunity and protection against subgroups A and B in mice. ImmunoHorizons, 2026. Shanghai Duoning Biotechnology Co., Ltd. Is a leading one-stop bioprocess solutions provider, dedicated to offering comprehensive solutions for biopharmaceutical products from R&D to commercial manufacturing, including reagents and consumables, instruments and equipment, and services. The company primarily operates two business segments: bioprocess solutions and laboratory products & services. Through its one-stop bioprocess platform, we help partners achieve efficient, stable, and cost- and quality-controlled drug development and manufacturing processes. Learn more: www.duoningbio.com Media: PR@duoningbio.com Swipe left/right to switch languages (CN/EN)