Photographer: Zoltan Mathe / AFP / Getty Images
Photographer: Zoltan Mathe / AFP / Getty Images
The AstraZeneca Plc coronavirus vaccine fared better than expected in a clinical trial in the United States, providing assurances about its safety and efficacy.
The injection developed with the University of Oxford was 79% effective in preventing Covid-19, and an independent monitoring board found no safety concerns, the company said Monday. The shot also protected all immunized people from serious illness and death in a study of more than 30,000 volunteers.
The results should increase confidence in the product after confusion about its true effectiveness and the best affected dosing regimen. The vaccine faced several setbacks, most recently about supply problems and possible side effects. Even after European Medicines Agency declared that it is safe last Thursday, not all countries in the European Union resumed vaccination under the concern of reports of blood clots.
“The effectiveness is better than we expected,” wrote Peter Welford, an analyst at Jefferies, in a note to customers. “It is important to note that, after recent security concerns largely unfounded in Europe, the study confirms the security profile.”
Read more: EU regulator considers Astra safe, but recommends warning label
Astra’s shares rose up to 1.2% in the London trades.
A deficit in deliveries to the EU has put Astra is in conflict with the bloc and has led authorities to oppose the region’s bullet exports while seeking to hold the company accountable.
Read more: Vaccine battle heats up with EU ready to halt UK remittances
Clinical trials in the UK and Brazil last year produced a range of readings due to different dosage amounts and regimens used, and at least 10 EU countries only approved the injection for children under 65 initially.
Data confusion
Many have since he reversed that decision after more real-world usage data showed that the vaccine was effective for everyone. Older adults accounted for about a fifth of the American test, which showed 80% effectiveness in this age group. Trials last year did not provide conclusive data due to the lack of participants over 65 years old.
Several cases involving severe blood clots found in individuals after inoculation have also damaged the image of the vaccine. More than a dozen countries suspended the use of the shot last week in the reports. European Medicines Agency and UK regulator He said Thursday that no definitive link could be established between the clots and the vaccine, and the benefits of using it continue to outweigh the risks. The US review study that found no safety issues looked specifically at blood clots.
Skepticism about the vaccine started last year. When Astra and Oxford The first reported data from clinical trials conducted in the UK and Brazil last November, they produced two very different readings of effectiveness of 62% and 90%. Because of a manufacturing error, a group of participants received a lower first dose, which produced the highest reading, compared to those who received two standard doses. Further analysis suggested that it was the difference in dosage, not the quantity, that created the difference.
More than 70 countries worldwide have approved the Astra-Oxford injection for use and partners plan to produce until three billion doses of the vaccine this year.
The vaccine is particularly important for the global effort to end the pandemic because it is easy to store and transport and the company provides it without profit during the crisis. Unlike vaccines for Pfizer Inc. and partner BioNTech SE, and Moderna Inc., which must be kept frozen, the Astra shot can be kept at the refrigerator temperature.
(Updates to add analyst comments in the fourth paragraph, actions in the fifth)