Last week two More and more pharmaceutical companies supported by the US federal government’s Operation Warp Speed program have announced preliminary results of large-scale clinical trials of their Covid-19 vaccines. And both had much appreciated results to report. Most.
According to Johnson & Johnson’s Press release, the company’s unique vaccine was 85% effective in preventing severe forms of the disease among 44,000 people enrolled in each of three trials in the United States, Latin America and South Africa. But when it came to fending off more mild cases of coronavirus infection, the vaccine worked best in the United States, where it was 72% protective compared to just 57% in South Africa. (Fire efficiency in Latin America was 66%.)
It was The same story with Novavax, a much smaller Maryland-based company. In its trial carried out in the United Kingdom on 15,000 people, the vaccine demonstrated an effectiveness of 89% against mild, moderate and severe cases of Covid-19; in the company’s small study in South Africa, the effectiveness rate fell to around 50 percent.
The dramatic difference probably comes down to particular versions of the coronavirus circulating in different places. Late last year, when Novavax and Johnson & Johnson were launching their South African trials, scientists in Durban discovered a new cluster of cases, all united by a unique constellation of mutations in the gene for the peak protein of the virus. This variant, known as B.1.351, has grown rapidly across the country, becoming the dominant strain in just a matter of weeks and fueling a massive outbreak of new infections.
Since the initial discovery of B.1.351, scientists around the world have sprint to better understand its changes. A series of non-peer reviewed studies posted as pre-print In recent weeks, one in particular, called E484K, has made it much more difficult for antibodies found in the blood of recovered Covid-19 patients and those with immunity to recognize version B.1.351 of the virus. Based on these lab experiments, scientists strongly suspected that the current class of licensed vaccines would still work against this strain – but perhaps just not as well. Data gathered from the Novavax and Johnson & Johnson trials now seem to reinforce this intuition.
“It’s a wake-up call for all of us,” Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said Friday during a White House press briefing. He acknowledged that the virus is evolving faster than previously thought and that the variants now spreading around the world will not be the end of its evolution. “This means that we, as government, businesses, all of us together, will have to be nimble to be able to adapt easily, to create versions of the vaccine specifically directed against the prevalent mutation at any given time,” he continued.
B.1.351 is one of at least three variants– including one first found in the UK and another in Brazil – it is believed to spread more easily than earlier forms of the coronavirus, although it is not yet clear how much more each is transmissible and to what extent they can cause re-infections. What is It’s obvious to scientists and public health experts that the United States, and indeed the world, is now in a race to vaccinate as many people as possible before these problematic mutations take hold. But at the same time, parallel efforts to develop and distribute multi-variant vaccines to control all existing strains must also begin. How will it actually work?
Executives from Pfizer and Moderna, the first companies to clear Covid-19 vaccines by the US Food and Drug Administration, said they were reorganizing their vaccines to strengthen protection against these new mutations, as a precaution. Moderna has gone so far to begin preparing for a Phase I study of a B.1.351-specific booster dose that would be given as a follow-up to people who already received the original vaccine.