The meningococcal conjugate vaccine is made from the sugar coating of the bacteria Neisseria meningitidis, the germ that is responsible for causing meningitis in adolescents. The chemical from the outer surface of the bacterium is extracted and purified, and it is then connected (conjugated) to the protein made by the diphtheria bacterium. The conjugation process is necessary because the protein from diphtheria alerts the immune system to the presence of the meningococcal coating much better than the sugar coating alone.

The vaccine also contains a small amount of formaldehyde (used to deactivate the protein from diphtheria bacterium). The vaccine does not contain any preservative or antibiotics. There is no trace of any animal tissue in this vaccine because both meningococcus and diphtheria are bacteria, and they do not need to be grown inside another cell to be produced in the laboratory.