This is a phase II, multicentre, multinational, randomized, parallel group, placebo-controlled study of four vaccination regimens in healthy pregnant women. There will be 5 treatment groups; Group 1 will receive one injection of placebo at 22 (±1) weeks gestational age (GA), one injection of GBS-NN/NN2 at 26 (±1) weeks GA and one injection of GBS- NN/NN2 at 30 (±1) weeks GA. Group 2 will receive one injection of GBS-NN/NN2 at 22 (±1) weeks GA, one injection of GBS-NN/NN2 at 26 (±1) weeks GA and one injection of placebo at 30 (±1) weeks GA.Group 3 will receive one injection of GBS-NN/NN2 at 22 (±1) weeks GA, one injection of placebo at 26 (±1) weeks GA and one injection of GBS- NN/NN2 at 30 (±1) weeks GA. Group 4 will receive one injection of placebo at 22 (±1) weeks GA, one injection of GBS-NN/NN2 at 26 (±1) weeks GA and one injection of placebo at 30 (±1) weeks GA.~Group 5 will receive an injection of placebo at 22, 26 and 30 weeks (±1) GA. Participants will attend the clinic for assessment visits up to delivery and for a further 3 visits at 28 (±4) days, 90 (±6) days and 180 (±14) days post delivery.~Babies will be also be assessed at delivery, and 28 (±4) days, 90 (±6) days and 180 (±14) days post delivery.
This is a phase II, multicentre, multinational, randomized, parallel group, placebo-controlled study of four vaccination regimens in healthy pregnant women. There will be 5 treatment groups; three groups of 60 participants will receive will receive two doses of GBS-NN/NN2 vaccine and one dose of placebo (saline); one group of 60 participants will receive one dose of GBS-NN/NN2 vaccine and two doses of placebo (saline), and one group of 60 participants will receive three doses of placebo (saline).