CDC Recommends Pfizer and Moderna Vaccines Over J&J

The Johnson & Johnson vaccine is staying on the market, but the preference for the Pfizer and Moderna mRNA vaccines stems from concerns about the rare but real risk of blood clots from the J&J vaccine.

The CDC has officially expressed a preference for the Pfizer and Moderna COVID-19 vaccines over Johnson & Johnson’s vaccine.

The agency’s endorsement, which was announced yesterday, comes after its committee of outside experts, the Advisory Committee on Immunization Practices (ACIP), made a recommendation favoring the mRNA vaccines. The recommendation arose out of concerns that the Johnson & Johnson vaccine can, in rare instances, trigger blood blots.

The J&J vaccine has the advantage of being a single-shot vaccine but its drawbacks relative to the Pfizer and Moderna vaccines have been apparent. In addition to the risk of blood clots, it is less protective against COVID-19 than the Pfizer or Moderna vaccines.

The FDA fact sheet on the J&J vaccine says that the blood clots appear to occur most often in women, ages 30-49, with the highest reported rate being 1 case per100,000 doses administered. About 15% of the blood clots following vaccination have been fatal, according to the FDA.

The Washington Post reported yesterday that nine deaths — seven women and two men — have been confirmed in connection with the blood clot issue through September.

The newspaper noted that it is unusual for the CDC and ACIP to express this kind of preference.

The J&J vaccine uses a weakened adenovirus to ferry a small piece of DNA of the SARS-CoV-2 virus that codes for the spike protein that the immune system recognizes. The Pfizer and Moderna vaccines also produce the recognizable spike protein, but they introduce mRNA instead of DNA to produce it. The delivery vehicle is also different. Instead of altered adenovirus, the mRNA is encased lipid nanoparticles — tiny fat particles.

The J&J vaccine is staying on the market. The official announcement from the CDC yesterday says the “ACIP reaffirmed that receiving any vaccine is better than being unvaccinated. Individuals who are unable or unwilling to receive an mRNA vaccine will continue to have access to Johnson & Johnson’s COVID-19 vaccine.”

This article originally appeared on Managed Healthcare Executive