Provided herein are combination vaccines comprising antigens for protecting a subject against at least diphtheria, tetanus, pertussis and Hib, wherein: (a) the antigen for protecting against Hib is a conjugate of a Hib capsular saccharide; (b) the concentration of the Hib conjugate in the vaccine is <;15 μg/ml; and (c) the Hib conjugate has never been lyophilized.