Moderna announces step toward updating COVID shots for fall
Moderna hopes to offer updated COVID-19 boosters in the fall that combine its original vaccine with protection against the Omicron variant. On Tuesday, it reported a preliminary hint that such an approach might work.
Today's COVID-19 vaccines all are based on the original version of the coronavirus. But the virus continues to mutate, with the super-contagious omicron variant -- and its siblings -- the latest threat.
Before Omicron came along, Moderna was studying a combination shot that added protection against an earlier variant named Beta. Tuesday, the company said people given that Beta-original vaccine combination produced more antibodies capable of fighting several variants -- including Omicron -- than today's regular booster triggers.
While the antibody increase was modest, Moderna's goal is to produce a combination shot that specifically targets Omicron. "These results really give us hope" that next step will work even better, said Dr. Jacqueline Miller, a Moderna vice president.
Tuesday's data was reported online and hasn't been vetted by independent experts.
COVID-19 vaccines still are providing strong protection against severe disease, hospitalization and death, even against Omicron. That variant is so different from the original coronavirus that it more easily slips past the immune system's defenses, although studies in the U.S. and elsewhere show an original booster dose strengthens protection. Some countries offer particularly vulnerable people a second booster; in the U.S., that's anyone 50 or older or those with a severely weakened immune system.
Health officials have made clear that giving boosters every few months isn't the answer to the mutating virus. They've begun deliberating how to decide if and when to change the vaccine recipe.
Just switching to a vaccine that targets the latest variant is risky, because the virus could mutate again. So Moderna and its rival Pfizer both are testing what scientists call "bivalent" shots -- a mix of each company's original vaccine and an omicron-targeted version.
Why would Moderna's earlier, beta-targeted combo shot have any effect on Omicron? It includes four mutations that both the beta variant and the newer Omicron have in common, Miller said.
Now Moderna is testing a bivalent shot that better targets Omicron -- it includes 32 of that variant's mutations. Studies of two booster doses are underway in the U.S. and Britain; results are expected by late June.
------
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute's Department of Science Education. The AP is solely responsible for all content.
COVID-19 COVERAGE
CTVNews.ca Top Stories
Engaged couple shot dead fleeing landlord after house dispute near Hamilton, Ont., police say
A 'truly innocent' engaged couple was shot dead while attempting to flee their attacker outside their home after a landlord-tenant dispute escalated on Saturday night, according to police.

Turkiye's Erdogan wins 5th term as president, extending rule into 3rd decade
Turkiye President Recep Tayyip Erdogan won reelection Sunday, extending his increasingly authoritarian rule into a third decade in a country reeling from high inflation and the aftermath of an earthquake that levelled entire cities.
Venice authorities investigate after canal turns fluorescent green
Venetian authorities are investigating after a patch of fluorescent green water appeared in the famed Grand Canal on Sunday morning.
Fight still ahead for Texas' Ken Paxton after historic impeachment deepens GOP divisions
The historic impeachment of Texas Attorney General Ken Paxton was just the first round of a Republican brawl over whether to banish one of their own in America's biggest red state after years of criminal accusations.
Blais scores twice, Canada beats Germany 5-2 to win gold at men's hockey worlds
Samuel Blais scored two goals to rally Canada to a 5-2 victory over Germany in the final of the ice hockey world championship on Sunday.
Jan. 6 rioters are raking in thousands in donations. Now the U.S. is coming after their haul
Less than two months after he pleaded guilty to storming the U.S. Capitol, Texas resident Daniel Goodwyn appeared on Tucker Carlson's then-Fox News show and promoted a website where supporters could donate money to Goodwyn and other rioters whom the site called 'political prisoners.'
3-year-old boy dies after drowning in backyard pool west of Toronto
Police are investigating the death of a three-year-old boy who was pulled from a backyard pool in Oakville on Saturday.
Alberta NDP holds rally in Calgary, UCP talks about crime, mental health supports
Alberta NDP Leader Rachel Notley held a major rally in downtown Calgary Saturday morning, while her United Conservative rival had no public events planned this weekend after a final pitch to voters a day earlier.
'The Little Mermaid' makes box office splash with US$95.5 million opening
'The Little Mermaid' made moviegoers want to be under the sea on Memorial Day weekend.