Data Inconclusive on Efficacy of Moderna Vaccine Against COVID-19 Variants

World Health Organization experts say more clinical evidence is needed to know whether the Moderna vaccine protects against COVID-19 variants. The conclusion came as WHO’s Strategic Advisory Group of Experts on Immunization, known as SAGE, issued interim recommendations for use of the Moderna vaccine against COVID-19.

Health officials are concerned about the new strains of COVID-19, which recently were found in South Africa and Britain and have since migrated to other places. The appearance of these variants has triggered consternation and many questions regarding their potential impact on the efficacy of newly developed vaccines against the coronavirus.

U.S. pharmaceutical company Moderna announced Monday its COVID-19 vaccine appeared to protect people against the emerging strains. WHO Director of the Immunization Department, Vaccines and Biologicals, Kate O’Brien, says she is aware of the report.

She noted Moderna, however, has just said it has the ability to modify the vaccine to work against the mutant strains but has not actually modified it. She said more clinical evidence was needed to know whether the two-dose regimen of the vaccine protects against the coronavirus variants.

“This is an area that we are concerned about, and I think the readiness of vaccine manufacturers and the preparedness that they have to potentially make modifications to the vaccines that they are continuing to develop is very welcome,” she said.

O’Brien says most of the available evidence indicates the vaccines in hand are an extremely valuable tool in fighting the pandemic and in ultimately crushing the virus.

Based on current evidence, SAGE members recommend an interval of 28 days between Moderna’s first and second shots. They say the interval between the two doses may be extended to 42 days only under exceptional circumstances.

SAGE Chairman Alejandro Cravioto said the experts oppose the preferential vaccination of international travelers against COVID-19, given the limited supply of available vaccines.

“We feel that unless the traveling is essential, people should try to stay home and keep the social distancing measures that have been put in place, that have been proven to be much better to prevent infection than any other measures so far,” Cravioto said.

The WHO recommends pregnant women not be inoculated with either the Moderna or Pfizer vaccines unless the benefit outweighs the potential vaccine risks. It cites as examples that vaccines would be beneficial for health workers at risk of exposure, and pregnant women with co-morbidities, who would be in danger of becoming severely ill from COVID-19.