CanSino Biologics Inc.’s experimental coronavirus vaccine showed promising results in a mid-stage clinical study, paving the way for the next phase of tests as it jostles with Western pharma giants to deliver one of the first pandemic vaccines.

The shot was shown to be safe and induced an immune response, according to a study released in the medical journal The Lancet. Still, the authors stressed that no participants were exposed to SARS-CoV-2 virus after vaccination, so it wasn’t possible for this study to determine whether the candidate effectively protects against infection.

The results reinforce CanSino’s status as a front-runner in the vaccine race. The company emerged as one of the fastest movers in May, when it became the first firm to publish a full scientific study on its early human trials -- a crucial step because it allows researchers to assess a pharmaceutical product’s potential.

CanSino’s experimental vaccine completed the second of three stages of human testing required before a pharmaceutical product can be sold. A shot from AstraZeneca Plc and Oxford University showed promise on Monday in the first phase of tests.

The coronavirus pandemic, which first emerged in Wuhan late last year, has provoked a powerful research push in China amid exacerbated political tensions with the U.S.

A number of vaccines developed by local companies are being tested on humans. Beijing has mobilized its health authorities, drug regulators and research institutes to work around the clock with local companies.