Effectiveness of COVID vaccines against virus variants
Moderna Inc. is planning to study multiple approaches to vaccine booster shots that could protect against emerging coronavirus variants, while gearing up to produce more doses of its shots this year and next.
In a statement, Moderna said it had completed manufacturing doses of a new version of its COVID-19 vaccine modified to target the South Africa strain, or B.1.351, and shipped it to researchers at the National Institutes of Health for clinical study. The South Africa booster shot is part of a multi-pronged strategy Moderna is taking against new variants, the company said.
In addition to the South Africa specific booster, the company is testing a third dose of its existing vaccine in a clinical study, and it also plans to test a booster that will combine the South Africa-specific vaccine and its existing vaccine, the company said. Clinical studies will be done both at the NIH and through Moderna.
Shares of Moderna rallied in after-hours trading in New York, rising more than 5.6 per cent.
Moderna said it plans to evaluate both the combined vaccine and the South Africa-specific one as an initial shot for people who haven’t yet been vaccinated.
Though its existing vaccine produces neutralizing antibodies against the South African strain, at reduced levels, Moderna is conducting the studies to be ready if researchers and governments decide that booster shots are needed.
“We want to make sure that people are immune in the long run both against the ancestral strain, which may or may not require a third dose, and against what could be an emerging variant of concern,” said Tal Zaks, Moderna’s chief medical officer, in an interview.
In a separate statement, the company said it was making new capital investments to increase manufacturing capacity and said that next year it plans to produce 1.4 billion doses, up from an earlier estimate of 1.2 billion doses. It also raised the low end of its COVID-19 production forecast this year to 700 million doses from 600 million doses. The high end of its range for this year is unchanged at 1 billion doses.
These production estimates are based on the existing dose of 100 micrograms. The company will test booster shots at lower doses, and if some of the production is switched to lower-dose booster shots, the output will be higher, the company said.
“Moderna is committed to making as many updates to our vaccine as necessary until the pandemic is under control,” said Moderna Chief Executive Officer Stephane Bancel, in a statement. “We hope to demonstrate that booster doses, if necessary, can be done at lower dose levels, which will allow us to provide many more doses to the global community in late 2021 and 2022 if necessary.”
In the interview, Zaks said the Food and Drug Administration has “agreed in principle” to Moderna’s plan for increasing the number of doses per vial to as many as 15 from 10. Getting approval for this plan is subject to Moderna providing supplemental manufacturing data to the agency, which will only take weeks, he said.
While the studies of booster shots will focus on people who had received Moderna’s vaccine, Zaks said that mRNA booster shots would be likely to work for people who received other vaccines initially. The company is in talks with other companies and government researchers about studies of Moderna booster shots in people who received another vaccine first, he said.
The company also said in a statement that it has delivered about 60 million COVID-19 vaccine doses globally, including 54.8 million in the U.S. It said another 32.8 million doses have been produced in the U.S. and are in vials awaiting the final stages of production and testing before being released.