According to the American National Institutes of Health (NIH), results from a large clinical trial in the United States and South America show that the AstraZeneca Covid-19 vaccine is well tolerated and protects against symptomatic Covid-19 disease. The NIH’s independent Data and Safety Monitoring Board (DSMB) overseeing the trial found no safety issues with the vaccine, AZD1222, the medical research agency said in a statement on Monday, according to Xinhua news agency.
The randomized, double-blind, placebo-controlled trial will begin in August 2020.
The study is based on the findings of 32,449 adult volunteer participants from 88 locations in the United States, Chile, and Peru.
For every two people who received AZD1222, one person received a placebo, resulting in nearly 20,000 people receiving the investigational vaccine.
Two doses of the vaccine were given four weeks apart.
According to the National Institutes of Health, AZD1222 has a statistically significant vaccine effectiveness of 78.9% in preventing symptomatic Covid-19 and 100% in preventing serious or critical illness and hospitalization.
Vaccine effectiveness against symptomatic Covid-19 was 79.9% in participants aged 65 and up.
According to the NIH, the DSMB reviewed blood clots and cerebral venous sinus thrombosis among participants and found no increased risk of these conditions in those who had been vaccinated.