RBI-4000

RBI-4000 is a self-replicating RNA (srRNA) vaccine developed by Replicate Bioscience for the prevention of rabies. It is designed to stimulate virus-neutralizing immune responses, providing prophylactic protection against rabies infection. In phase 1 clinical trials, RBI-4000 demonstrated robust immunogenicity and safety, eliciting protective antibody responses at all tested dose levels—including doses as low as 0.1 micrograms—when administered intramuscularly. The majority of participants achieved or surpassed the World Health Organization's threshold for protective rabies neutralizing antibodies after a single dose, with efficacy comparable to licensed vaccines such as RabAvert and RavAvert. The vaccine was well tolerated with no serious adverse events or dose-limiting toxicities observed[1][3][4][5][6][8].