Merck Focusing on Combination Vaccine

Merck & Co. Inc. has stopped production and sales of its monovalent vaccines for measles, mumps and rubella. The manufacturer instead plans to focus on its combination vaccine, MMRII.

Merck spokeswoman Amy Rose said MMRII accounts for 98 percent of the company's volume for measles, mumps and rubella vaccines, compared to just 2 percent from monovalent vaccines Attenuvax (measles), Mumpsvax (mumps) and Meruvax (rubella).

"The combination vaccine is what's recommended, and it's such a significant portion of the orders we see," said Rose. "It's in the best interest of public health to make more of that rather than dedicate manufacturing capacity to monovalents."

Rose said Merck had not decided when, or if, it might make the monovalent vaccines available for sale in the future.

Doug Campos-Outcalt, M.D., M.P.A., who serves as the AAFP's liaison to the CDC's Advisory Committee on Immunization Practices and is a former member of the AAFP Commission on Clinical Policies and Research, said Merck's decision was insignificant in terms of public health. He added, however, that some parents likely will be unhappy.

"The use of the single antigen is pretty limited," he said. "There's no harm if you need one in getting all three. There are some parents out there that want a delayed vaccine schedule. They want the vaccines spread out over a longer period of time and not so many at once. That's a lot of hooey. Alternative schedules have never been proven to be superior."