Vaccine Take of RV3-BB Rotavirus Vaccine Observed in Indonesian Infants Regardless of HBGA Status

Histo-blood group antigen (HBGA) status may impact vaccine efficacy due to rotavirus strains binding to HBGAs in a P genotype-dependent manner. This study aimed to determine if HBGA status impacted vaccine take of the G3P[6] neonatal vaccine RV3-BB.DNA was extracted from stool samples collected in a subset of participants (n=164) of the RV3-BB Phase IIb trial in Indonesian infants. FUT2 and FUT3 genes were amplified and sequenced, with any single nucleotide polymorphisms analysed to infer the Lewis and secretor status. Measures of positive cumulative vaccine take were defined as serum immune response (either immunoglobulin A or serum neutralising antibody) and/or stool excretion of RV3-BB virus. Participants were stratified by HBGA status and measures of vaccine take.In 147/164 participants, both Lewis and secretor phenotype were determined. Positive vaccine take was recorded for 144/147 participants with combined phenotype determined (97.9%). Cumulative vaccine take was not significantly associated with either secretor status (risk ratio (RR)=1.00, 95%CI=0.94-1.06, p=0.97) or Lewis phenotype (RR=1.03, 95%CI=0.94-1.14, p=0.33). Nor was a difference observed when analysed according to each of the individual components of vaccine take.The RV3-BB vaccine produced positive cumulative vaccine take, irrespective of participant HBGA status in Indonesian infants.