..........
According to the World Health Organization, as of July 14,
around the world, and 23 of them had started clinical trials involving humans. But only two have reached Phase 3 -- the last scientific stage before approval to be marketed -- which requires large-scale trials with thousands of individuals to assess the efficacy and safety of the vaccine.
..........
Julio Barbosa, a 42-year-old nursing technician who has already lost five colleagues to the coronavirus, has volunteered to participate in one of the mass vaccination trials, conducted by Oxford University and pharmaceutical company AstraZeneca. The Phase 3 trial will involve 50,000 volunteers worldwide.
...........
Chinese biotech company Sinovac is also beginning a Phase 3 trial in Brazil, in collaboration with Brazil's Butantan Institute in Sao Paulo. Its CoronaVac trial vaccine uses inactivated virus cells to stimulate an immune response in patients. The tests will begin next Monday with 9,000 volunteers in
plus the capital.
..............