This Phase 2 study will enroll 910 healthy male/female volunteers 19-80 years of age.

Stage IIa: Group 1- FINLAY-FR-2 (Experimental): high dose RBD conjugated to TT (batch 1) + adjuvant; 0.5 mL by intramuscular route. Treatment scheme: 0-28 days. Presentation: Vial with single dose.

Group 2- FINLAY-FR-2 (Experimental): high dose RBD conjugated to TT (batch 2) + adjuvant; 0.5 mL by intramuscular route. Treatment scheme: 0-28 days. Presentation: Vial with single dose.

Stage IIb: Group 1- FINLAY-FR-2 (Experimental): high dose RBD conjugated to TT (batch 1) + adjuvant; 0.5 mL,by intramuscular route. Treatment scheme: 0-28 days. Presentation: Vial with single dose.

Group 2- FINLAY-FR-2 (Experimental): high dose RBD conjugated to TT (batch 2) + adjuvant; 0.5 mL by intramuscular route. Treatment scheme: 0-28 days. Presentation: Vial with single dose.

Group 3 Placebo (control): 0.5 mL by intramuscular route. Treatment scheme: 0-28 days. Presentation: Vial with single dose.