Vaccine Roundup

How Vaccines Are Faring Against the Variants

A roundup of the most important Covid-19 vaccine news this week

Yasmin Tayag
Medium Coronavirus Blog
4 min readJan 29, 2021


Photo: William Campbell/Getty Images

There are still 20 vaccines in phase 3 trials, eight approved for limited use, and two approved for full use in some countries after fully completing phase 3 trials — the vaccines from Pfizer/BioNTech and Sinopharm. (Those from Moderna and Oxford-AstraZeneca are being used with emergency use approval in some countries.) More are on their way.

The limited vaccine supply worldwide is raising concerns as new cases surge again, and the Biden administration is attempting to secure additional doses. New vaccines in the final stages of testing, however, offer a much-needed ray of hope.

Biden is trying to buy 200 million more doses for the U.S.

Vaccines are in short supply in the U.S. and around the world because of manufacturing constraints. Nevertheless, nations are trying to secure what they can. On Tuesday, the Biden administration announced it was attempting to buy 200 million more doses of the vaccine — 100 million from Pfizer/BioNTech and 100 million from Moderna — and that these were expected to arrive by the end of the summer. Together with the total 400 million doses already promised to the U.S., the additional doses would be enough to cover 300 million Americans. The success of this plan, of course, rests on the ability of manufacturers to keep production rates up.

Europe’s vaccine supply is dwindling as cases surge

Case counts are soaring in Europe, and vaccine doses are in short supply there too. The rollout of vaccines across the European Union has been a “fiasco,” as Elad Simchayoff put it in the Coronavirus Blog. On January 28, Spain became the first European country to partially suspend its immunization efforts because of a lack of doses, as NPR reported. Germany’s plans are also delayed because of shortages. France, meanwhile, is considering extra restrictions to curb the spread of the virus. Both Pfizer/BioNTech and AstraZeneca have had to delay deliveries of additional doses to the European Union.

Novavax releases promising data on its vaccine

On Thursday, promising new data from the Maryland-based vaccine maker Novavax offered a welcome bit of respite. (In case you’ve forgotten, Novavax is the little-known company that the Trump administration invested $1.6 billion in through Operation Warp Speed.) As the New York Times reported, the company said that an early analysis of its 15,000-person trial in Britain showed an efficacy of nearly 90%. The company is also running trials in the U.S., Mexico, Brazil, and South Africa, however, and a study of about 4,000 people in South Africa suggested that its efficacy rate there is under 50%. South Africa is where the more highly transmissible variant known as B.1.351 was first identified, and on Thursday, it was detected in the U.S. for the first time, in South Carolina.

Novavax’s vaccine isn’t an mRNA vaccine, like those from Pfizer and Moderna. Instead, it’s protein-based, relying on well-established technology. The Times reported that the company is already working on a version of its vaccine, possibly administered as a booster shot, that can address new variants. Results from its U.S. trial are expected in April, and an application for approval will likely follow suit.

Johnson & Johnson also releases promising data

Not to be outdone, Johnson & Johnson released long-awaited phase 3 trial data on its vaccine on Friday, which was similar to that of Novavax in that it showed a strong efficacy rate against the coronavirus — 72% in the U.S. and 66% across all trial sites — but a lower one against the variant from South Africa, at 57%. As the New York Times reports, Johnson & Johnson said it plans to apply for emergency use authorization in the U.S. as soon as next week. What’s most promising about Johnson & Johnson’s vaccine is that it requires only a single dose and needs only standard refrigeration.

Moderna is considering adding a booster shot to address variants

Early research has suggested that Moderna’s vaccine is less effective — though still effective — against the variant from South Africa. As STAT News reported Monday, Moderna’s vaccine is sixfold less effective against the new variant than it is against the original. To address this, Moderna is looking into adding a booster shot to its current two-dose regimen and will explore a booster to specifically target B.1.351. Moderna’s vaccine, fortunately, doesn’t appear to be any less effective against B.1.1.7, the so-called U.K. variant.

Merck bows out of the vaccine race

Merck, one of the world’s leading vaccine makers, announced on Monday that it would shelve the two Covid-19 vaccines it had in development. The vaccines, the company said, were safe but produced “inferior” immune responses compared to natural infection and other vaccines already in use. Merck will, however, continue to develop two therapeutic Covid-19 drugs, one of which the U.S. has already secured up to 100,000 doses of in a $356 million deal. Now that Merck is out of the picture, eyes are on the vaccines from Novavax and Johnson & Johnson.



Yasmin Tayag
Medium Coronavirus Blog

Editor, Medium Coronavirus Blog. Senior editor at Future Human by OneZero. Previously: science at Inverse, genetics at NYU.