Oliver Berg | alliance d’image | Getty Images
In the trial, Moderna is testing a 50 microgram dose of its vaccine in previously vaccinated individuals. He found that the booster dose increased neutralizing antibody responses against the original virus as well as against B.1.351 and P.1, two variants that have since spread to other countries, including the United States. .
The company also said that a booster shot of its other vaccine, which it calls mRNA-1273.351, generated an even better immune response compared to its current vaccine against South Africa’s B.1.351 variant. The new vaccine is a variant specific booster shot to target B.1.351.
The preliminary results, which Moderna says will be published online, have yet to be peer reviewed.
Moderna said the side effects were similar to those seen after the second dose of the vaccine in previously reported studies. Side effects included pain at the injection site, fatigue and headaches, as well as muscle and joint pain.
The new data comes as drugmakers and scientists now say people are likely to need a booster shot of Covid-19 vaccines and possibly additional doses each year, just like with seasonal flu.
Moderna’s vaccine requires two doses given four weeks apart. Like Pfizer and Johnson & Johnson, the shot is very effective against Covid, although executives and company officials now say they expect this strong protection to wane over time. The Pfizer vaccine is also a two dose regimen while the J&J vaccination is just a jab.
White House chief medical adviser Dr Anthony Fauci has previously said Americans may need to get vaccinated to better protect themselves against the variants.
A Centers for Disease Control and Prevention report released on Wednesday predicted that Covid-19 cases would increase until May – due to the highly contagious B.1.1.7 variant first identified in the UK – before decreasing sharply in July as vaccinations would reduce infections. Still, variants threaten to reverse the nation’s progress, officials said,
“We are finding that our current vaccines protect against the variant contaminants circulating in the country. Simply put, the sooner we get more and more people vaccinated, the sooner we will all get back to normal, ”said Dr. Rochelle Walensky, director of the CDC. during a White House press briefing on Covid.
Moderna is evaluating three approaches to increase immunity. The first approach would use variant-specific booster shots, such as mRNA-1273,351, but at a lower dose than the original vaccine. The second would combine the original vaccine with a variant-specific vaccine into a single injection at 50 micrograms or less, Moderna said. The third would test a third dose of the original vaccine at a lower dose.
Bancel told CNBC last month that the company was hoping to have a booster shot for its two-dose vaccine available in the fall.