Johnson & Johnson (NYSE:JNJ) has gained some ground in the coronavirus vaccine race. On Thursday, the pharmaceutical and consumer goods company announced that in pre-clinical studies, its Ad26.COV2-S vaccine candidate had demonstrated effectiveness in protecting on non-human primates from infection with SARS-CoV-2.

In contrast to other coronavirus vaccine candidates -- such as the one many observers view as the most promising, Moderna's mRNA-1273 -- Johnson & Johnson's produced its response with a single dose.

A researcher using a petri dish.

Image source: Getty Images.

Based on those results, Johnson & Johnson has begun testing its candidate on humans in phase 1/2a clinical trials in the U.S. and Belgium. For those studies, Ad26.COV2-S will be administered in single- and double-dose regimens; the company will use the trials to gauge its safety, immunogenicity (the ability to produce an immune response), and potential for causing adverse reactions.

More than 1,000 healthy adults between the ages of 18 and 55, plus a cohort 65 and older, will participate in the trials. The company is also planning to conduct a phase 2a trial in the Netherlands, Spain, and Germany, and a phase 1 study in Japan.

Johnson & Johnson aims to advance Ad26.COV2-S through the clinical study process with some haste. "The findings give us confidence as we progress our vaccine development and upscale manufacturing in parallel, having initiated a Phase 1/2a trial in July with the intention to move into a Phase 3 trial in September," said Chief Scientific Officer Paul Stoffels.

A raft of major pharmaceutical companies, as well as numerous biotechs, are developing vaccine candidates, drugs, or both to combat COVID-19. But while a couple of drugs have shown some promise as treatments for the novel coronavirus, no vaccine candidate for it has yet demonstrated its effectiveness in a phase 3 trial -- the pivotal step before one could win regulatory approval and be brought to market for the public.

On Thursday, Johnson & Johnson shares bucked the bearish trend of the market by rising -- albeit only by 2%.