AstraZeneca Vaccine 100% Effective In Preventing Severe Disease And Hospitalizations, U.S. Trials Show - Forbes

Topline

The AstraZeneca-Oxford Covid-19 vaccine was 79% effective against symptomatic Covid disease and 100% effective in preventing severe disease and hospitalizations in its U.S. Phase III trial, the drug maker said in a press release on Monday, highlighting the safety and effectiveness of the vaccine amid suspension of its use in some countries over safety concerns.

Key Facts

Citing independent safety monitoring of the trials, AstraZeneca said it found no increased risk of blood clots among the 21,583 participants who received at least one dose of the vaccine and no instances of cerebral blood clots were recorded in the trial.

The drug maker noted that the vaccine’s effectiveness was consistent across age groups and showed 80% efficacy in participants aged 65-years and older.

The large-scale Phase-III U.S. trials featured 32,449 participants, mostly from America but also included some participants from Chile and Peru.

Participants who received the vaccine were given two doses at a four week interval, however, AstraZeneca noted an extended interval of 12 weeks between shots has demonstrated even greater efficacy in previous trials.

Around 20% of the participants were older than 65 and 60% had comorbidities—such as diabetes, severe obesity or cardiac disease—which increase the risk of severe disease.

AstraZeneca will prepare for the primary analysis of the trial to be submitted to the U.S. Food and Drug Administration (FDA) for Emergency Use Authorization in the coming weeks.

Big Number

4 million. That’s the total number of doses of the AstraZeneca vaccine the Biden administration plans to send to neighbors Mexico and Canada, White House Press Secretary Jen Psaki said last week. Although the U.S. has not yet approved the vaccine for emergency use, AstraZeneca plans to have 30 million shots ready in the country at the beginning of April.

What To Watch For

It remains to be seen if the U.S. will approve the AstraZeneca shot after raising concerns about the botched global trials in November. A manufacturing error had led to the use of two separate dosing regimens of the vaccine in the global trials last year. However, the new trial data presents more robust evidence of efficacy and safety with standardized doses and this may allow the vaccine to be finally approved for use in the U.S.

Crucial Quote

Oxford Professor Sarah Gilbert, who co-designed the vaccine, told BBC News: “In many different countries and across age groups, the vaccine is providing a high level of protection against Covid-19 and we hope this will lead to even more widespread use of the vaccine in the global attempts to bring the pandemic to an end.”

Key Background

The AstraZeneca vaccine has been at the center of controversy over the past two weeks as several European countries temporarily suspended the use of the shot over concerns that it was causing cerebral blood clots. On Thursday, the European Medicines Agency (EMA) ruled out a broad link to blood clotting but said it was unable to definitively rule out an association with extremely rare clotting events. After the EMA’s review several countries like Germany, Italy and France restarted the use of the shot while others like Norway and Denmark have continued to pause the rollout. The flip-flop over the vaccine has eroded confidence about the shot among people in Europe, many of whom are now avoiding the vaccine and waiting for a substitute. The AstraZeneca vaccine is viewed as being critical for global immunization due to it being cheaper, easier to manufacture and easier to handle than the mRNA vaccines from Pfizer and Moderna.