A Phase 3 Double-blind, Randomized, Active Comparator-controlled, Group-sequential, Multinational Trial to Assess the Safety, Immunogenicity and Efficacy of a Trivalent Rotavirus P2-VP8 Subunit Vaccine in Prevention of Severe Rotavirus Gastroenteritis in Healthy Infants

The trial will be a multinational, randomized, double-blind, double-dummy, endpoint driven, group-sequential, active comparator-controlled study, in which participating infants will be randomized 1:1 to receive either: 1) 90 µg of the TV P2-VP8 vaccine IM plus oral placebo, or 2) Rotarix® per os (PO) plus IM placebo. Participants will receive three doses of TV P2-VP8/placebo IM and two doses of Rotarix®/placebo PO at monthly intervals starting at ≥6 to <8 weeks of age, administered concomitantly with EPI/UIP vaccines. To maintain the blind, infants allocated to the TV P2-VP8 vaccine arm will receive both TV P2-VP8 IM as well as oral placebo vaccine, and infants allocated to receive Rotarix® will receive both Rotarix® PO and placebo IM. Active surveillance for episodes of gastroenteritis (GE) will be conducted throughout the study, through weekly contact with participants' parents. Unsolicited AEs grade ≥ 2 through 28 days after the last study vaccination will be recorded in the study database, as will data for SAEs (including intussusception) throughout the study.