AstraZeneca and Oxford University’s Covid-19 vaccine is more effective when its second dose is given three months after the first, instead of six weeks, a peer-reviewed study published in The Lancet medical journal showed on Feb. 19.

The World Health Organization listed AstraZeneca’s Covid-19 vaccine for emergency use, widening access in the developing world, while sources said the EU is in talks with Moderna on buying more vaccines.

Britain launched a trial to assess the immune responses generated if doses of the Covid-19 vaccines from Pfizer Inc. and AstraZeneca Plc are combined in a two-shot schedule.

Oxford University and AstraZeneca’s Covid-19 vaccine showed in a study it had 76% efficacy against symptomatic infection for three months after a single dose, which increased if the second shot is delayed, backing Britain’s vaccine rollout policy.

The data continues to come in on the various Covid-19 variants, and so far the news is pretty good, according to BioSpace.

British Prime Minister Boris Johnson said the Covid-19 vaccine developed by Oxford University and AstraZeneca is effective across all age groups, after Germany recommended the shot be given only to under-65s.

Laboratory testing found that Regeneron Pharmaceuticals Inc.’s Covid-19 antibody cocktail can combat a coronavirus variant first found in South Africa, but a similar drug from Eli Lilly and Co. is inactive against it, according to a study.

Global coronavirus cases surpassed 100 million on Jan. 27, according to a Reuters tally, as countries around the world struggle with new virus variants and vaccine shortfalls.

AstraZeneca denied the company’s Covid-19 vaccine is not very effective for people over 65 years old, after German media reports said officials fear the vaccine may not be approved in the European Union for use in the elderly.

U.S. public health officials said a second Covid-19 shot could be administered as much as six weeks apart from the first one in situations where it was not possible to get a booster dose immediately.