(Yicai Global) July 21 -- A Chinese research team conducted the second-phase clinical trial of a Covid-19 vaccine whose results show the vaccine is safe and induce immune responses in humans, the team said in a paper appearing yesterday in the distinguished British medical journal the Lancet. The vaccine is China's first to have entered phase-one clinical trials.

Phase two involved over 500 volunteers with a median age of 39.7, a larger range of participants than phase one, in a randomized, double-blind, placebo-controlled trial that sought to discover whether the vaccine can induce immune responses in recipients and is safe, and the results came back in the affirmative, per the paper.

The trial provides further evidence than phase one of the vaccine’s safety and immunogenicity in a larger population, which is an "important step" in evaluating candidate vaccines, the paper stated, adding the team is now conducting the phase three trial.

Academician Chen Wei from the Institute of Bioengineering at the Institute of Military Medicine under the Academy of Military Science of the Chinese People's Liberation Army, and Prof. Zhu Fengcai from Jiangsu Provincial Center for Disease Control and Prevention participated in the test. The team also completed phase one and published its results.

Recipients of the vaccine have not been exposed to the coronavirus since their vaccination, and thus the trial results are not dispositive of whether the vaccine can protect against infection, and more evidence is needed from the phase three trial, the researchers noted.

Around 250 Covid-19 vaccines are under development worldwide, and at least 17 of them are under evaluation in clinical trials, the paper said.

In a double blind test both the subject and observer are unaware the exercise is a test. Deemed the gold standard, the tests are used in both theoretical and practical experiments in medicine and psychology.

Editor: Ben Armour