CanSino Biologics's candidate COVID-19 vaccine is 65.7% effective at preventing symptomatic cases based on results from final phase clinical tests, Fortune reported on Tuesday.
The drug, scientists said, adds a one-shot experimental vaccine to the world's growing inoculations against the virus.
CanSino's single-dose COVID-19 vaccine Ad5-nCoV showed a 91% efficacy rate in preventing serious cases of the disease during preliminary evaluations, Faisal Sultan, special assistant to the Pakistani Prime Minister on Health, said.
The clinical trials showing 65.7% efficacy was conducted in several nations including Pakistan. CanSino is China's third vaccine maker to release an efficacy data in its late-stage trials.
In addition to Pakistan, the Chinese biotech has tested its vaccine in Argentina, Chile and Mexico. No serious cases linked to the vaccine had been reported in clinical tests across the world.
According to Sultan, the result was based on a multiple-location analysis of CanSino's third-stage clinical tests, but the Pakistan subset that enrolled 30,000 subjects showed a moderately more robust numbers of almost 75% protection against symptomatic cases.
A COVID-19 vaccine must provide at least a 50% protection rate to be considered safe and effective, as required by the world's leading vaccine authorities and the World Health Organization.
"One vaccine, single visit and cheaper logistics, it has all those advantages," Sultan was quoted by Bloomberg as saying in a phone interview on Tuesday.
Meanwhile, a shot developed by state-run China National Biotec Group, a unit of Sinopharm, proved to be 78% effective, while one from Sinovac had a 50.38% rate in a clinical test involving high-risk health workers.
