Enrollment for BNT164a1 and BNT164b1 will be conducted independently, and in parallel. The trial will enroll participants into six cohorts by dose level who will be stratified by interferon gamma release assay (IGRA) status and then randomized 5:1 for BNT164 (BNT164a1 or BNT164b1):placebo. The trial will use a staggered dose escalation schema, i.e., enrollment into the next higher dose level is done sequentially and subject to safety data from the previous dose levels, with sentinel participants for Dose 1 in all cohorts.
This randomized, placebo-controlled, observer-blind, safety and dose-finding Phase Ib trial will be conducted in countries in Africa, including Republic of South Africa. This trial will evaluate three dose levels of the BNT164 investigational vaccines (BNT164a1 and BNT164b1) to select a safe and tolerable dose in a three-dose schedule.