Merck Issues Voluntary Recall of Two Vaccines

Whitehouse Station, NJ (Dec. 12)-Merck & Co. initiated a voluntary recall of 11 lots of its Haemophilus influenzae type B vaccine “Pedvaxhib”  [Haemophilus b Conjugate Vaccine (Meningococcal Protein Conjugate)] and two lots of its combination Haemophilus influenzae type B–hepatitis B vaccine “Comvax” [Haemophilus b Conjugate (Meningococcal Protein Conjugate)]. The recall is specific to these 13 lots and does not affect any other vaccines manufactured by Merck. The affected doses of Pedvaxhib and Comvax were distributed starting in April 2007.

Merck is conducting this recall because it cannot confirm the sterility of these specific vaccine lots. The potential contamination of these specific lots was identified as part of Merck’s standard evaluation of its manufacturing processes, said the company in a press release. Routine testing of the vaccine-manufacturing equipment that produced Pedvaxhib and Comvax identified the presence of Bacillus cereus bacteria, according to a MedWatch Alert issued by the US Food and Drug Administration. Sterility tests of the vaccine lots that are the subject of this recall have not found any contamination in the vaccine.

“The potential for contamination of any individual vaccine is low, and, if present, the level of contamination would be low,” said Merck in a press release.  “However, because the company cannot assure the sterility of these specific lots of vaccine, it is conducting this recall.”

Merck is working with FDA and the US Centers for Disease Control and Prevention to inform affected healthcare providers of this recall. Merck is also in the process of communicating with public-health authorities and healthcare providers in the US and in other countries where these lots were distributed, as appropriate.

Physicians are advised not to administer any vaccine from the lots being recalled. Individuals who received vaccine from these lots should complete their immunization series with a Haemophilus b conjugate-containing vaccine not affected by this recall, but do not need to be revaccinated to replace a dose they received from a recalled lot. The efficacy of the vaccine was not affected.