In the United States, vaccines are licensed by the Center for Biologics Evaluation and Research (CBER) of the Food and Drug Administration on the basis of their demonstrated safety and efficacy and the demonstrated ability of the manufacturer to produce a consistent product. After licensure, vaccines are generally released to the market on a lot-by-lot basis, following CBER's review of lot-release testing results. A lot is released only if it meets all predefined specifications. A discussion of US vaccine regulation was published recently by Parkman and Hardegree.1
See also p 849.
As reported in this issue of THE Journal,2 during studies of the interchangeability of licensed Haemophilus influenzae type b (Hib) polysaccharide-protein conjugate vaccines, Anderson et al found that a lot of Hib vaccine with the capsular polysaccharide conjugated to the meningococcal outer membrane protein complex (PedvaxHib, Merck and Co, West Point, Pa) produced lower than expected immune
Egan W, Frasch CE, Anthony BF. Lot-Release Criteria, Postlicensure Quality Control. and the Haemophilus influenzae Type b Conjugate Vaccines. JAMA. 1995;273(11):888-889. doi:10.1001/jama.1995.03520350070032