Will emerging variants make the leading vaccines less protective?
As the COVID-19 pandemic in the U.S. surpasses the one-year mark, the numbers are sobering: more than 27 million Americans infected; a death toll of over half a million.
Despite uncertainty about the pandemic’s future, appreciation of the scale and speed of healthcare innovation is warranted. Vaccines to protect against the SARS-CoV-2 virus were developed and deployed in less than a year. The FDA issued emergency use authorizations for two COVID-19 RNA vaccines at the end of 2020: the Pfizer-BioNTech vaccine and the Moderna vaccine. New drugs, such as the monoclonal antibody bamlanivimab, have joined steroids in improving treatment for patients.
But in January and most of February the pace of the distribution of the vaccines wasn’t as remarkable as that of the vaccine and treatment research. Many states had not received the number of doses they were promised. Pfizer said millions of doses of its vaccine were in storage, a situation that may change after the company and the FDA agreed the vaccine could be stored at normal freezer temperatures. As of Feb. 28, the CDC’s COVID-19 vaccine tracker showed 75.2 million doses had been administered, and Bloomberg’s tracker showed 78% of the doses supplied to the states had been administered.
President Joe Biden has vowed to speed up the rollout, bolstering the distribution plan with a $20 billion national vaccination program. He also announced the purchase of another 200 million doses of vaccines from Moderna and Pfizer-BioNTech and an increase in the number of doses being shipped to the states.
Back in the pack
Meanwhile, the emergency use authorization for Johnson & Johnson’s vaccine means there will be three vaccines available in the U.S. The company submitted its request for an emergency use authorization (EUA) in early February, and the go-ahead from the FDA came on Feb. 27. The EUA was based on phase 3 results that showed the J&J Johnson is 66% effective at preventing moderate to severe cases of COVID-19 compared with the 95% protection against symptomatic COVID-19 seen in late-stage trials of the Pfizer-BioNTech and Moderna vaccines.
But the J & J vaccine has the advantage of being a one-dose vaccine that could mean more coverage. Novavax, a relatively small biotech company in Gaithersburg, Maryland, is a David among the Goliaths in the race to deploy a COVID-19 vaccine. Novavax reported positive phase 3 trial results at the end of January. The company will most likely seek approval in the U.K. before the U.S.
The Oxford-AstraZeneca vaccine has had a bumpy ride. The U.K.’s equivalent of the FDA approved emergency use for the vaccine in late December based on results that showed 62% efficacy from two doses but, oddly, higher efficacy among the study volunteers who received a low dose followed by a standard one. In early February, preliminary data showed that it was effective in reducing transmission after just one dose, a result that led to consideration of whether a vaccine strategy emphasizing single doses might make sense. A few days later, however, other data showed that the vaccine was only 22% effective against the South African variant, or B.1.351, of SARS-CoV-2. As a result, South African officials halted its use in that country.
GlaxoSmithKline’s website states that it is one of the largest vaccine companies in the world, with a portfolio of more than 30 vaccines that generated about $9 billion in revenues last year. But GlaxoSmithKline is well off the pace when it comes to COVID-19 vaccines. A vaccine it was developing with Sanofi had to be redesigned when it failed to trigger immunity in older people. In February, it announced that it was building on an existing relationship with CureVac, a German biopharmaceutical company, to develop a “multivalent approach (to COVID-19 vaccines) to address multiple emerging variants in one vaccine.”
Here come the variants
The desire for good news and progress against the pandemic may have led to a premature sigh of relief when the Pfizer-BioNTech and Moderna became available in the U.S. The emergence of variants in January and February may be another setback in the yearlong effort to stem COVID-19 infections, illness and death. Three notable variants have been detected in the U.S.:
Naturally, there’s some worry that these new variants will evade the protective effect of the current crop of vaccines — and the vaccine-lit end of the COVID-19 tunnel will darken. But variance doesn’t necessarily mean immunological evasion; some preliminary data suggest that the current crop of vaccines and vaccine candidates will do just fine against the U.K. strain. There is more concern about the South African variant — and not just with respect to the AstraZeneca-Oxford vaccine. A study of Novavax’s vaccine among 4,400 people in South Africa showed that the vaccine was just 49% effective against the South Africa variant.
A Moderna study of a small group of people who received two doses of its vaccine showed antibody levels that would likely fend off the variants, especially the U.K. one. Moderna has also developed a version of its vaccine that is tailored to produce an immune response to South African variant. A phase 1 trial was of that vaccine is scheduled to start this month.
Jaime Rosenberg is a freelance writer based in Jersey City, New Jersey.