Johnson & Johnson (NYSE:JNJ) announced on Wednesday that it expects to begin a phase 1/2a clinical trial of its COVID-19 vaccine candidate Ad26.COV2-S, recombinant, in the second half of July. The company previously projected that the early-stage clinical study would begin in September.

In February, Johnson & Johnson established a partnership with BARDA (the Biomedical Advanced Research and Development Authority) to develop a COVID-19 vaccine candidate at an accelerated pace. Chief Scientific Officer Paul Stoffels noted that the strong preclinical data observed thus far and the company's discussions with regulatory authorities were key in allowing it to speed up the development program.

IMAGE SOURCE: GETTY IMAGES.

The early-stage clinical trial will be conducted in the U.S. and in Belgium. Johnson & Johnson plans to enroll 1,045 healthy adults between the ages of 18 to 55, plus adults aged 65 and over.

Johnson & Johnson is also talking with the National Institutes of Allergy and Infectious Diseases about the possibility of starting a phase 3 study of its COVID-19 vaccine sooner if the early-stage studies produce positive results. The healthcare giant is ramping up manufacturing capacity for the experimental vaccine even before clinical testing is completed, with a goal of being able to supply over 1 billion doses next year if the vaccine proves safe and effective.

10 stocks we like better than Johnson & Johnson

When investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.*

David and Tom just revealed what they believe are the ten best stocks for investors to buy right now… and Johnson & Johnson wasn't one of them! That's right -- they think these 10 stocks are even better buys.