Clover Reports Positive Results for RSV Vaccine SCB-1019 in Comparison with GSK's AREXVY

Clover Biopharmaceuticals, Ltd., a global biotechnology company based in Shanghai, announced promising results from its Phase I trial of the SCB-1019 RSV vaccine candidate. This non-adjuvanted bivalent RSV vaccine was tested against GSK’s adjuvanted AREXVY. The company revealed that their vaccine candidate showed a potential best-in-class combined efficacy and safety profile.

The trial involved 70 older adults and elderly subjects who received either Clover’s SCB-1019, GSK's AREXVY, or a saline placebo. The immunogenicity results indicated that SCB-1019 induced comparable levels of RSV-A and RSV-B neutralizing antibodies to AREXVY by Day 28. Specifically, SCB-1019 generated geometric mean titers (GMTs) of approximately 30,500 IU/mL for RSV-A, surpassing AREXVY’s 26,700 IU/mL and significantly higher than the placebo’s 3,300 IU/mL. For RSV-B, SCB-1019 prompted GMTs of about 32,000 IU/mL, closely following AREXVY’s 37,700 IU/mL and vastly outpacing the placebo’s 2,900 IU/mL. Additionally, SCB-1019 showed a 1.5-fold higher trend in RSV-B specific antibodies compared to AREXVY, hinting at a broader immunological response upon re-vaccination.

Safety and tolerability were substantial highlights of the trial. SCB-1019 demonstrated significantly lower rates of local adverse events (AEs) at 16.7%, compared to 76.7% for AREXVY. The non-adjuvanted vaccine was generally well-tolerated, with local and systemic AEs being mild and comparable to those observed with the saline placebo. There were no vaccine-related serious adverse events, adverse events of special interest, or events leading to discontinuation in the SCB-1019 group.

Joshua Liang, CEO & Board Director of Clover, expressed optimism about the trial’s outcomes, emphasizing the potential of SCB-1019 to address unmet needs in RSV prevention. He highlighted the importance of effective re-vaccination and broad protection against respiratory diseases caused by RSV-related viruses. Liang confirmed that Clover plans to commence further clinical trials in 2025, focusing on SCB-1019’s application in RSV re-vaccination settings and its integration into a respiratory combination vaccine.

Clover Biopharmaceuticals, established as a leader in innovative vaccines, aims to improve global health through its comprehensive vaccine pipeline. The company integrates research, development, manufacturing, and commercialization capabilities. With strategic partnerships worldwide, Clover is dedicated to reducing the burden of vaccine-preventable diseases and making advancements toward preventing more diseases through vaccination.

The announcement underscores Clover’s commitment to leveraging cutting-edge vaccine technology to address critical health challenges. The promising Phase I trial results for SCB-1019 open the door to future studies that could potentially establish Clover’s RSV vaccine candidate as a key tool in combating respiratory syncytial virus infections, especially in vulnerable older populations.