This study reports the preliminary assessment of the safety and immunogenicity of the first serogroup C conjugate vaccine candidate that includes meningococcal P64k recombinant protein as the carrier (MenC/P64k). Twenty volunteers were recruited for a double-blind, randomized, controlled phase I clinical trial, receiving a single dose of MenC/P64k (study group) and a single dose of the commercial polysaccharide vaccine AC (control group). Only mild reactions were observed. No statistical differences were detected between the antipolysaccharide C IgG responses of both groups as well as between bactericidal serum titre (P > 0.05). The MenC/P64k vaccine was found to have a good safety profile, to be well tolerated and immunogenic.