Omicron has drug companies preparing for the worst. Here are their plans to counterattack the newest COVID-19 variant.

• Drug companies are preparing for Omicron to be the next major challenge of the pandemic.
• The newest variant's mutations could weaken vaccine protection, though that remains unknown.

Vaccine and drug developers are preparing for the Omicron variant to turn into the next major challenge of the pandemic.

The new variant, first identified in South Africa, has already spread to at least 10 countries around the world, with confirmed cases in places such as the UK, Australia, Germany, and Canada. The World Health Organization labeled the new strain a "variant of concern" on Friday, and the world is now waiting on laboratory research to clarify just how threatening Omicron may be.

The biggest questions are still unanswered, particularly how the leading vaccines and treatments hold up against Omicron. Experts say they are worried because this new variant carries more than 30 mutations to its spike protein, the target for the vaccines and many treatments. The fear is these changes to the virus may help it evade protection from vaccination or an antibody infusion.

"On the face of it, it looks pretty gnarly," Robert Nelsen, a managing director of Arch Venture Partners, told Insider.

Vaccine developers are already preparing Omicron-specific boosters

Drug companies have been preparing for this moment. The vaccine manufacturers Moderna, Pfizer, and BioNTech have talked up their ability to quickly update their vaccines to new strains thanks to the flexibility of their mRNA-based shots. While they are also waiting for definitive data on how the vaccine formulations hold up, they are already jumping into action.

"This is the highest level of alert we've ever been on, by far," Stephen Hoge, Moderna's president, told The Washington Post.

Hoge called Omicron's dozens of mutations "a Frankenstein mixture of the greatest hits." They carry some of the changes that raised alarm with variants such as Beta and Delta. Omicron has additional mutations that aren't well studied yet, he added.

Previous lab studies have shown that the vaccines produce fewer neutralizing antibodies against the Beta and Delta variants. Those lower antibody levels are still protective, but some experts suspected that the changes cause protection to wane faster.

Moderna announced its Omicron strategy on Friday. The Massachusetts biotech has started developing a booster shot tailored to the new variant. The company has already started clinical trials for other booster shots, including a version of its vaccine that includes mutations previously seen in the Beta and Delta variants that are also present in Omicron.

Pfizer and BioNTech are also evaluating an Omicron-specific booster shot. Pfizer has said it can have a new shot ready to manufacture and distribute in less than 100 days.

Other vaccine developers are also scrambling to respond. Johnson & Johnson said on Monday that it's also working on an Omicron-specific vaccine. Novavax, a Maryland biotech, said on Friday that it's starting to develop an Omicron shot that could begin testing and manufacturing in a few weeks, if needed.

Not all agree that Omicron-specific shots are the best approach. Tillman Gerngross, the CEO of the antibody developer Adagio Therapeutics, told Insider that a variant-specific shot was a "fool's errand" given how quickly new strains emerge. Gerngross' company is focused on making COVID-19 antibody treatments that are variant-resistant.

Vaccine developers previously created a Beta-specific shot, only to have Delta take over by the time it was ready for clinical study, he said.

"Chasing the waves is an idiotic idea in my view," Gerngross said.

Antiviral treatments could play a larger role as the Omicron variant spreads

Nelsen, a longtime biotech venture capitalist who sits on the board of Vir Biotechnology, said he was confident Omicron would have less effect on the new COVID-19 pills developed by Pfizer and Merck compared to the vaccines.

"The antivirals should work," Nelsen said, although he didn't believe Merck's drug would be much help after a new analysis showed that it was 30% effective at preventing hospitalizations and deaths.

Instead, Nelsen said Pfizer's pill, which showed an 89% reduction in hospitalizations and deaths, could still have a major effect on the pandemic despite Omicron's mutations. Pfizer has said it plans to produce 80 million treatment courses by the end of 2021.

Unlike the leading vaccines, these antiviral pills don't target the spike protein, so experts are confident they may still be effective against a new variant.

Albert Bourla, Pfizer's CEO, said in a Monday interview on CNBC that he had a "very, very high level of confidence that the treatment will not be affected" by Omicron.

Both antiviral treatments are being reviewed by the Food and Drug Administration, with an expert panel set to meet on Tuesday to review and vote on Merck's drug, which was codeveloped with Ridgeback Biotherapeutics.

Antibody drugs could see a major shake-up in leading manufacturers

There's more uncertainty with antibody drugs. These treatments are typically given as IV infusions, delivering antibodies to patients that can help fight COVID-19. A range of companies have produced antibody drugs that are now in use, including Regeneron Pharmaceuticals, Eli Lilly, AstraZeneca, Vir-GlaxoSmithKline, and Celltrion.

Preliminary research from the lab of Jesse Bloom, a biologist at the Fred Hutchinson Cancer Research Center, indicated that Regeneron's drug could "take a hit," and that Lilly's cocktail could also be in trouble against the Omicron variant. But Bloom cautioned on Twitter that it was too early to say for sure how Omicron would affect these drugs, with more research needed.

Some new biotechs see Omicron as an opportunity to show the value of their approaches. Adagio, for instance, was founded in 2020 to develop a COVID-19 antibody drug that could withstand variants. Its stock has more than doubled since last Wednesday, soaring to a $4.9 billion valuation.

Gerngross, Adagio's CEO, said the company's research suggested that its experimental antibody drug wasn't affected by Omicron.

Adagio's antibody is still in clinical trials to see whether it can treat or prevent COVID-19, with pivotal results expected by the middle of 2022, Gerngross said. Adagio expects to produce 2 million treatment courses next year.

A key challenge may be raising awareness of monoclonal antibodies with clinicians and patients, and making it easier to get access, said Dr. Kavita Patel, a primary-care physician in Washington and former White House health-policy director.

"It is just a beast to try to get people monoclonals," Patel said. She added that this weekend she had to send a patient to a Connecticut emergency room to get access to antibodies.

Overall, Omicron may draw more attention to treatments, particularly if the vaccines are less effective against the variant.

"We are at a pivotal moment again in this pandemic," Gerngross said.