Moderna booster shots show positive results against stubborn strains
Moderna’s Covid-19 booster shots gave positive results against immune system-evading strains that emerged in South Africa and Brazil, according to early results from a mid-stage trial.
Two types of booster shots studied spurred higher levels of virus-halting antibodies against the strain P.1 that hit Brazil and B.1.351, common in South Africa, Moderna said. One of the boosters is an additional low-dose shot of its existing vaccine, while the other type is customised against the South Africa strain.
The boosters, tested in 40 participants, were administered as a third shot six to eight months after the two-shot immunisation with the current vaccine. Antibodies from the initial vaccination were detectable in 37 of those people, but in about half the participants, the antibodies performed poorly against the variants that have pummelled South Africa and Brazil.
Moderna raised its 2021 sales forecast for its COVID-19 shot by 4.3% to $19.2 billion on Thursday, reflecting demand from countries looking to return to normalcy through rapid vaccine rollouts. Deals for “booster” doses, nations looking to stock up supplies for 2022 and beyond and a likely authorization for use of the vaccines in kids have led Moderna and its larger rival Pfizer to ramp up their supplies.