On September 3, 2026, Simcere Pharmaceutical Group Limited (02096) announced that Clulevibart Injection (brand name: Inmular®), a domestically developed Category 1 innovative biologic developed by Reyoung (Shandong) Biopharmaceutical Co., Ltd. ("Reyoung Bio"), received marketing approval from China's National Medical Products Administration (NMPA; approval number: Guoyao Zhunzi S20260068). Simcere and Reyoung Bio are collaborating on the commercialization of the product.
Clulevibart is approved for the prevention of respiratory syncytial virus (RSV)-associated lower respiratory tract infection (LRTI) in neonates and infants born at a gestational age of at least 35 weeks who are entering or were born during their first RSV season. The indication excludes children with chronic lung disease, including bronchopulmonary dysplasia, or clinically significant congenital airway abnormalities. As the first domestically developed long-acting RSV prophylactic monoclonal antibody approved in China, Clulevibart expands access to a domestically supplied option for infant RSV prophylaxis.
RSV is a leading cause of LRTI in infants and a major cause of hospitalization for bronchiolitis and pneumonia, with children under two years of age facing a particularly high disease burden. RSV infection during infancy has also been associated with recurrent wheezing, a higher risk of asthma, and persistent impairment of lung function, placing a substantial burden on children, families, and healthcare systems.
Pharmacological management of RSV in infants currently consists primarily of supportive or symptomatic treatment for active infection and monoclonal antibody prophylaxis. The prophylactic monoclonal antibodies currently available in China are imported, highlighting the clinical and public health importance of expanding access to domestically developed alternatives.
Clulevibart is a recombinant human IgG1 kappa monoclonal antibody that confers passive immunity by targeting antigenic site II of the RSV fusion (F) protein. Fc engineering extends its half-life, allowing a single intramuscular injection to provide sustained protection throughout an RSV season. Because it provides passive immunity, Clulevibart can achieve protective antibody concentrations rapidly after administration and offers a prophylactic option for infants for whom no active immunization option is currently available.
On August 20, 2026, Simcere Pharmaceutical Group and Reyoung Bio entered into a strategic partnership under which Simcere obtained exclusive commercialization rights for Clulevibart in Greater China. The product is developed and manufactured in China, which is expected to support a stable and predictable domestic supply.
Approval was supported by a pivotal multicenter, randomized, double-blind, placebo-controlled Phase III trial. At Day 150, Clulevibart demonstrated 85.32% efficacy in preventing medically attended RSV-associated LRTI, defined as an outpatient visit, emergency department visit, or hospitalization, and 83.27% efficacy in preventing RSV-associated hospitalization compared with placebo. At Day 240, efficacy was 82.04% against medically attended RSV-associated LRTI and 78.44% against RSV-associated hospitalization. A Phase IIIb study in children aged one to two years is underway to evaluate use in a broader age group.
Dr. Yunshu Zhou, President of Simcere Pharmaceutical Group, said: "Clulevibart is a domestically developed innovative biologic with substantial clinical value and strengthens Simcere's anti-infective portfolio. By drawing on our nationwide commercialization network and broad market reach, we will work to improve access following launch so that more infants and families in China can benefit from this new prophylactic option."
Dr. Xuelian Zhao, Chief Executive Officer of Reyoung Bio, said: "Simcere brings an established infectious disease portfolio, extensive commercialization capabilities, and broad market coverage. Through our collaboration, we aim to realize the clinical and public health value of Clulevibart and make this domestically developed, long-acting RSV prophylactic therapy available to more infants and their families."
About Simcere
Simcere Pharmaceutical Group Limited is a pharmaceutical company driven by innovation and focusing on four therapeutic areas including Neuroscience, Oncology, Autoimmune Diseases and Anti-infection. We proactively explore areas with significant unmet needs, and our mission is ‘For patients, for life’. Driven by our in-house R&D efforts and synergistic innovation, Simcere has established strategic cooperation partnerships with many innovative companies and research institutes. Learn more at www.simcere.com.
About Reyoung Bio
Reyoung (Shandong) Biopharmaceutical Co., Ltd. specializes in the research, development, and commercialization of antibody-based biologics. The company focuses on passive immunization for the prophylaxis and treatment of infectious diseases and is also exploring tumor immunotherapy. Guided by its mission, "Nourishing life, warming families," Reyoung Bio combines proprietary technology platforms with the identification and screening of rare samples from elite responders to discover and develop first-in-class antibodies with high specificity, high affinity, and broad-spectrum activity. The company is committed to developing differentiated therapies for major diseases. For more information, visit www.reyoungbio.com.