China has granted approval to assess a third coronavirus vaccine candidate against Covid-19 in the second phase of clinical trials.

According to state-run Xinhua news agency, an inactivated vaccine created by Wuhan Institute of Biological Products under the China National Pharmaceutical Group, Sinopharm, and the Wuhan Institute of Virology (WIV) entered clinical trials.

An inactivated vaccine is made of virus particles, bacteria or other pathogens, which are grown in culture and lack disease-producing capability.

In the first phase trial of the vaccine candidate, a total of 96 volunteers across three age groups were injected as of 23 April. Sinopharm said that the candidate demonstrated good safety profile so far, with the trial participants still under observation.

The randomised, double-blind and placebo-controlled trials of the vaccine are conducted in Jiaozuo, Henan Province. The second phase trial is set to focus on the vaccination procedure, noted the company.

The Covid-19 vaccine candidate will also undergo the third phase of the trial. It is expected that the safety and efficacy study will take approximately one year to complete.

China also approved an adenovirus vector vaccine, which was developed by Institute of Military Medicine under the Academy of Military Sciences. This candidate was the first vaccine to enter a clinical trial in the country.

The first phase of the trial was completed in March and the second phase began on 12 April.

Earlier this month, China-based Sinovac Biotech received approval for a clinical trial of an SARS-CoV-2 vaccine candidate to protect from Covid-19.

The company started developing the candidate at the end of January this year. It conducted preclinical studies in alliance with academic research institutes in the country.

Findings from an animal challenge study showed that the vaccine candidate protects animals with no antibody-dependent enhancement (ADE).