Moderna says new Covid vaccine was effective against Eris variant in early trial

Moderna's new Covid vaccine generated a robust immune response against the now-dominant Eris variant and another rapidly spreading strain of the virus in an early clinical trial, the biotech company said Thursday. 

The updated shot is designed to target omicron subvariant XBB.1.5, but the results suggest that the jab may still be effective against newer variants of the virus that are gaining ground nationwide. That includes Eris and another variant nicknamed Fornax, both of which are also descendants of the omicron virus variant. 

Moderna's vaccine and new shots from Pfizer and Novavax are slated to roll out within weeks, pending potential approvals from the U.S. Food and Drug Administration. 

Meanwhile, Covid-related hospitalizations fueled by Eris and other variants continue to accelerate but remain below the summer peak that strained hospitals this time last year.

Eris, also known as EG.5, accounted for 17.3% of all cases as of earlier this month, according to the Centers for Disease Control and Prevention. 

The World Health Organization designated Eris a "variant of interest," meaning it will be monitored for mutations that could make it more severe. 

Fornax, or FL 1.5.1, is also beginning to surge in parts of the U.S. It accounted for 8.6% of all cases nationwide as of earlier this month, the CDC said.

A Pfizer spokesperson on Thursday said the company's own updated Covid shot effectively neutralized XBB.1.5 and Eris, among other variants, in a recent trial on mice.