Merck Withdraws Vaccines on Sterility Fears

Merck has initiated a voluntary recall of 11 lots of its Haemophilus influenzae type B vaccine, PEDVAXHIB, and two lots of its combination Haemophilus influenzae type B/ hepatitis B vaccine, COMVAX . 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.

The company is conducting this recall because it can not assure sterility of these specific vaccine lots. Routine evaluation of manufacturing processes revealed the potential contamination of the lots in question. Sterility tests of the vaccine lots that are the subject of this recall have thus far 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,” according to a company statement. Still, the company contends that the risk is large enough to warrant a recall.

Merck is working closely with the FDA and CDC to inform affected healthcare providers of this recall. The company is also in the process of communicating with public health authorities and healthcare providers in the U.S. and in other countries where these lots were distributed, as appropriate.

“We are taking this action because we are committed to ensuring the quality of our vaccines,” said Mark Feinberg, M.D., Ph.D., vice president, Medical and Policy Affairs, Merck Vaccines and Infectious Diseases. “We know that our vaccines can play an important role in the nation’s public health system, and we are committed to resolving this issue as quickly as possible to ensure that our vaccines are readily available.”

Physicians are advised not to administer any vaccine from the vaccine 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.