The American pharmaceutical giant Pfizer and German company BioNTech have said on Monday that their COVID-19 vaccine candidate is more than 90% effective in preventing coronavirus among those without evidence of prior infection. The vaccine trials at Pfizer are in the last stage.

In a month, the final analysis of the trials will be out. By the end of this year, as many as 50 million doses will be made available globally). As many as 39,000 volunteers have received their second dose of the vaccine. So far, no serious safety concerns have been reported.

TIME has reported that Pfizer has announced that its vaccine successfully prevented 90% of infections compared to a placebo. This is a great day for science and humanity, Pfizer said in a statement.

Howard Forman, a health policy and economics professor, is positive about the vaccine candidate. However, he has sounded cautious. "We know nothing about the durability of immunity. This will take time. But this first step is critical. Subgroup analysis will be very important. We need to know how effective this is for different age groups, different ethnic and racial groups, etc. This will take time," he tweeted out.