CHICAGO, Jan 28 (Reuters) – After developing and deploying COVID-19 vaccines at record speeds, drug manufacturers are already facing rapidly evolving coronavirus variants that could make them ineffective, a challenge that will require months of research and a large financial investment, according to disease experts.
Executives from Moderna Inc. and Pfizer Inc. and their partner BioNTech SE are studying new versions of their vaccines to address the most worrying variants identified to date. This is just part of the work needed to stay ahead of the virus, about a dozen experts told Reuters.
A global monitoring network needs to be built to assess emerging variants. Scientists need to establish what level of antibodies will be required to protect people against COVID-19 and determine when vaccines need to be modified. And regulators need to convey what is needed to show that up-to-date vaccines remain safe and effective.
“At this point, there is no evidence that these variants have changed the equation in terms of vaccine protection,” said Dr. Michael Osterholm, an infectious disease expert at the University of Minnesota. “But we have to be prepared for that.”
Johnson & Johnson told Reuters that the concerning variant first identified in South Africa has attracted attention and will adjust the vaccine accordingly if necessary. Pfizer said it could produce a new vaccine relatively quickly, but a senior vaccine executive said manufacturing it presents additional challenges.
The urgency of this effort is clear.
On Monday, Moderna said lab studies showed that antibodies made in response to its vaccine were six times less effective at neutralizing a lab-created version of a South African variant than previous versions of the virus.
A study published on Wednesday before the expert review found that the South African variant reduced neutralizing antibodies by 8.6 times for the Modern vaccine and 6.5 times for the Pfizer / BioNTech shot, although a A separate study backed by Pfizer published Wednesday suggests its vaccine could be more resistant. Modern said this week that it is starting work on a possible boost.
IT COULD TAKE MONTHS
It is not yet known to what extent protection may be lowered before a COVID-19 vaccine should be altered. With the flu, an eight-fold drop in vaccine-induced antibody protection means time to refresh. This does not necessarily apply to this coronavirus.
“The problem is that we don’t know what the coronavirus cut-off point is,” said Dr. John Mascola, director of the Vaccine Research Center at the National Institute of Allergy and Infectious Diseases (NIAID). scientists of whom helped develop the Modern vaccine.
Mascola said both studies that tested the Modern vaccine against the South African variant are roughly in the “same park.” Antibody protection may be high enough from the vaccine to be effective, he said.
NIAID scientists are analyzing data from the Modern phase final assay to see what level of neutralizing antibodies are required for protection. They are comparing vaccinated people but who got sick anyway with vaccinated people who stayed healthy.
It could take two months to complete this work, Mascola said. They hope to produce a benchmark for the minimum level of vaccine-induced antibodies needed to protect against COVID-19.
A global surveillance network is also needed to identify new worrisome variants as they emerge, similar to that used for monitoring rapidly mutating influenza viruses. This could cost between ten and hundreds of millions of dollars in the United States alone.
Richard Webby, an influenza surveillance expert at St. Louis Children’s Research Hospital. Jude said the United States could probably build a system to identify variants fairly quickly. The development of the ability to determine whether current vaccines are being evaded will take longer.
Currently, the United States conducts genetic sequencing to look for changes in the virus in only 0.3% of positive coronavirus tests. This is evident compared to 10% in the UK, which was the first to discover a major mutation in the virus that increases transmission by at least 50%. Experts said countries should sequence at least 5% of positive cases to detect significant changes in the virus.
Companies are waiting for the U.S. Food and Drug Administration to pass the tests that will be needed for the altered vaccines, said Phil Dormitzer, one of Pfizer’s leading viral vaccine scientists. With flu vaccines, companies can make changes without new trials. “But that’s after doing it for 50 years,” he said.
Peter Marks, who oversees the FDA’s vaccine approval process, said small trials testing up-to-date vaccines on about 400 participants may be needed at first. Even that could add months to the process.
Norman Baylor, chief executive of Biologics Consulting and a former FDA vaccine official, said the agency will chart the regulatory path. But public health agencies like the U.S. Centers for Disease Control and Prevention and the World Health Organization will decide when vaccines should be updated, as with the flu.
Altering the Pfizer vaccine would require “a very small change,” Dormitzer said.
Like Moderna, it uses messenger RNA (mRNA) technology, which is based on synthetic genes that can be generated and manufactured in weeks.
He estimates the company could make a prototype version in a week or so and it will take two more months to expand and upgrade the lab tests.
J&J, which is expected to publish final-phase test data on its vaccine in a matter of days, has laid the groundwork for addressing the worrying virus changes, scientific director Paul Stoffels told Reuters. His essay included sites in South Africa, which should give the company information about this variant.
If a change is needed, Stoffels said J&J would likely add a second strain to the existing vaccine.
“We’re looking at it very closely,” he said.
Report by Julie Steenhuysen in Chicago and Michael Erman in New York; Edited by Caroline Humer and Bill Berkrot