The purpose of this study was to evaluate the safety and reactogenicity of a single oral dose of heat-stable rotavirus vaccine (HSRV) in healthy adults aged 18–45 years, followed by an evaluation of the safety, reactogenicity, and immunogenicity of three doses of HSRV in healthy infants aged 6–8 weeks at enrollment. Adults were subjected to a single-center randomized controlled, sequential, blinded, and open-label study (infants). Fifty eligible adults were randomly assigned in a 1:1 ratio (HSRV: Placebo), followed by 50 eligible infants in a 1:1 ratio. Adults were given a single dose of HSRV or a placebo and were monitored for 14 days. Infants were given three doses of either HSRV or a placebo, with a 28-day follow-up after each dose. Adult and infant safety and reactogenicity assessments included both solicited and unsolicited adverse events (AEs), as well as any serious adverse events (SAEs), whereas serum anti-rotavirus IgA response rates were only included in the infant immunogenicity assessment. 

In this study, HSRV did not result in an increase in solicited adverse events in adults when compared to placebo. In infants, HSRV had a similar safety profile to the comparator in terms of solicited AEs. The percentage of infants with a threefold increase in serum anti-rotavirus IgA titers from baseline to 1-month post-dose 3 in the HSRV group was 88 percent, while the percentage in the comparator group was 84 percent. HSRV was found to be immunogenic in infants and generally well-tolerated in adults.