Between Nov 22 , 2013 , and Feb 25 , 2014 , we randomly assigned 42 participants to receive the low dose ( n = 12 ) , the medium dose ( n = 12 ) , or the high dose ( n = 12 ) of the measles-virus-based candidate vaccine , or Priorix ( n = 6 ) , of whom 36 participants ( 86 % ; n = 9 , n = 12 , n = 10 , n = 5 , respectively ) were included in the per-protocol population .