2021 forecast: COVID-19 vaccine rollouts: What's next for Pfizer and Moderna's mRNA shots, and which vaccines might come next?

coronavirus vaccine
In less than a year since the pandemic started, the first COVID-19 vaccines are reaching Americans. (nevodka/iStock/Getty Images Plus/Getty Images)

It’s been a tough year for humanity, but, with two COVID-19 vaccines rolling out, 2021 might look significantly different. That'll all depend on how the rollouts go, of course, but with multiple shots launching—and more in various stages of testing—there's reason to finally be optimistic.

So, what should people expect from the shots—and biopharma in general—as the vaccinations steadily ramp up in the coming months? For each individual, the timing of vaccinations will depend on age, risk factors and geography, but in general, officials say there's a light at the end of the tunnel.

In less than a year, Pfizer/BioNTech and Moderna conducted clinical testing, submitted their programs to the FDA and won emergency authorizations. The U.K. approved the Pfizer shot Dec. 2, and limited vaccinations started the following week. European regulators just this week signed off on the Pfizer shot.

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But winning an FDA authorization isn't the finish line. It'll be a monumental challenge for Operation Warp Speed and logistics partners to distribute the vaccines and for healthcare workers to administer shots to hundreds of millions of people as COVID-19 continues to spread apace. An early back-and-forth between Pfizer and the U.S. government over dose delivery underscored some of the potential challenges ahead.

Right on the heels of the emergency authorizations, companies began distributing doses. As of Monday, The New York Times reported that at least 556,000 people had received their first dose of a coronavirus vaccine—just as Moderna vaccines started rolling across the U.S. Meanwhile, Warp Speed head Moncef Slaoui, Ph.D., has told CNN the U.S. could have herd immunity in May if an aggressive nationwide immunization program goes as planned.

"If" is a big word, though. The mRNA vaccines' cold chain requirements and attendant logistics hurdles are well known, but they're not the only challenges. The two-dose format will require a massive database to track doses and ensure people who get a first dose also get a second, and on time. Plus, it isn’t yet known how long the vaccines will protect against COVID-19, which means revaccinations might be needed down the line.

Nevertheless, states and localities have formulated their own distribution plans and submitted them to the Centers for Disease Control and Prevention (CDC). In a public database, ProPublica has made available those initial plans. In early December, CDC experts determined healthcare workers and long-term healthcare facility residents should be the first to get vaccines.

On the ground in Northern California, Caesar Djavaherian, co-founder and chief clinical innovation officer of Carbon Health, said his team was “encouraged” that healthcare workers and people at the highest risk of contracting coronavirus will get the first vaccines. But he's noticed some hesitancy among front-line workers about getting mRNA shots, an entirely new technology.

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Some colleagues wonder about being “first in line” for mRNA vaccines when there isn’t “visibility” on the duration of protection or the potential for as-yet-unknown side effects, he said. And if doctors aren’t sure, the general population could rightly be expected to harbor their own reservations, Djavaherian said.

His company, a chain of healthcare clinics in California, New York, Florida, Alabama and Nevada, hasn’t been privy to planning conversations around vaccine deployment, Djavaherian said. The ER doctor estimates that fall 2021 is a more realistic timeline for herd immunity in the U.S. from vaccines.

If more vaccines with different characteristics end up making it to market, Djavaherian said he expects people at a lower risk of severe outcomes will be offered “whatever is available” and “easy to distribute.” For those at higher risk, the government will likely prioritize supplies of the best vaccines. That’s already happening in influenza, Djavaherian points out, as people 65 and older get shots with a higher dose.

Aside from the Pfizer and Moderna shots, AstraZeneca’s AZD1222, a replication-deficient chimpanzee viral vector vaccine, turned in 70% efficacy in a phase 3 trial, but a dose error in the trial has raised questions. In the pivotal trial, a mistakenly given half-dose of the vaccine, administered to 2,741 people, outperformed the full dose, prompting AZ to start a new half-dose trial. Even after the error, though, the U.K. government asked its drug regulator to consider a temporary approval. AstraZeneca’s CEO has said the company will need another trial to win U.S. approval.

Behind those programs, Johnson & Johnson and Novavax are also in phase 3 testing and plan to release their initial efficacy results soon, each with the aim to produce around a billion doses in 2021. Dozens of other programs are in early stages of research, too.

In a note last week, Bernstein analysts said they expect 200 million Americans to be vaccinated against the novel coronavirus by May 31, and that the people remaining at that point will either have refused the vaccine or found themselves ineligible. The analysts expect hundreds of millions of doses from Pfizer and Moderna to be delivered through their Warp Speed deals, but also expect "some contribution” from the Johnson & Johnson and Novavax programs. Those companies are set to report efficacy data in early 2021.

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The analysts have said the five leading vaccine players—Pfizer, Moderna, AstraZeneca, Novavax and Johnson & Johnson—will generate about $38.5 billion in COVID-19 shot sales next year. Pfizer and Moderna will take the biggest slices of the pie, the analysts predict, but the other players will still see multibillion-dollar opportunities. The team predicts around 2 billion vaccinations taking place in 2021, with the U.S. and other developed markets hitting herd immunity along the way.