Healthy male and non-pregnant female subjects between the ages of 18 and 65 were enrolled and randomized 1:1:1:1 to one of four study arms to receive 0.5 mL ( standard dose ) of vaccine subcutaneously ( SQ ) at : ( A ) days 0 , 14 ; ( B ) days 0 and 28 ; ( C ) days 0 , 14 , and 28 ; or ( D ) 0.25 mL at days 0 , 14 , and 28 .