To the Editor.
—The information regarding SmithKline Beecham's diphtheria-tetanus—acellular pertussis (DTaP) vaccine, Infanrix, as well as Tripedia (manufactured by Connaught Laboratories, Inc), presented in a Medical News & Perspectives1 article is misleading on several counts.The efficacy attributed to Tripedia is not in agreement with the manufacturer's own package insert, which states that, when adjusted for confounding factors, efficacy was calculated to be 80%.2 According to the Food and Drug Administration (FDA), Tripedia has been estimated to be between 69% and 80% effective, depending on the study.3 The article also implies that Tripedia has been granted licensure for a fifth dose following priming with Tripedia. The FDA has, in fact, requested more data before considering approval of the fifth dose for children primed with Tripedia.Regarding Infanrix, the article refers to an increase in rates of reactogenicity with successive doses without reference to what is known about
Howe BJ. Diphtheria-Tetanus—Acellular Pertussis (DTaP) Vaccine. JAMA. 1996;276(22):1803. doi:10.1001/jama.1996.03540220027023