China-based Clover Biopharmaceuticals Ltd. (HKG: 2197) has announced encouraging additional immunogenicity and safety data from its Phase I trial of SCB-1019, a non-adjuvanted bivalent RSV prefusion-stabilized F (PreF)-Trimer subunit vaccine candidate. The trial assessed SCB-1019 against GSK (NYSE: GSK)’s AS01E-adjuvanted RSV vaccine, Arexvy, in elderly subjects.
In the ongoing Phase I trial, 70 elderly participants were enrolled, receiving either Clover’s SCB-1019, Arexvy, or a saline placebo. At day 28, the non-adjuvanted SCB-1019 demonstrated geometric mean titers (GMTs) for RSV-A and RSV-B neutralizing antibodies (nAbs) comparable to those induced by the AS01E-adjuvanted Arexvy, with no statistically significant differences noted. Notably, SCB-1019 (bivalent RSV-A/B) showed an approximately 1.5-fold higher trend in antibodies against a potent RSV-B specific neutralization epitope in Site V compared to Arexvy (monovalent RSV-A), based on exploratory competitive-ELISA assays. This suggests the potential for greater and more sustained immunological breadth upon re-vaccination, pending confirmation in future studies.
Encouraged by these positive Phase I results, Clover plans to initiate further clinical trials in 2025 to evaluate SCB-1019 in an RSV re-vaccination setting and as part of a respiratory combination vaccine.- Flcube.com
