Johnson & Johnson begins study of one-dose COVID vaccine

Johnson & Johnson has begun dosing up to 60,000 volunteers in a study of its COVID-19 vaccine, marking the first big U.S. trial of an inoculation that may work after just one shot.

J&J became the fourth vaccine maker to move its candidate into late-stage human studies in the U.S. If enrollment goes as expected, the trial could yield results as soon as the end of the year, allowing the company to seek emergency authorization early next year, should it prove effective, according to Chief Scientific Officer Paul Stoffels.

“A single dose could be a very efficient tool to combat the pandemic as it is faster acting,” he said Wednesday in an interview. Animal models and early human studies showed that one shot of its vaccine generated a strong immune response in just 15 days, he said.

The final-stage study will pit the vaccine against a placebo injection, with a goal of showing whether it reduces cases of moderate to severe COVID-19, “the most important part of the disease to prevent,” Stoffels said. J&J is also looking at whether the shot curbs the virus’s spread.

The company’s shares rose as much as 2.3% in New York.

The New Brunswick, New Jersey-based company published detailed trial plans on Wednesday. Front-runners Pfizer Inc., Moderna Inc. and AstraZeneca Plc have already done the same in a broader transparency push.

“It is likely that multiple COVID-19 vaccine regimens will be required to meet the global need,” said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, in a statement. J&J’s vaccine “may be especially useful in controlling the pandemic if shown to be protective after a single dose.”

The study is nearly two months behind those of Moderna, working with NIAID, and Pfizer, partnered with BioNTech SE, whose final-stage trials started in late July. Pfizer has said it could get efficacy results by the end of October. Those vaccines use two-dose regimens.

J&J’s vaccine could offer an advantage in distribution over those inoculations, which require vaccination sites to ensure recipients return for their second dose.

The company also said its vaccine can be stored at refrigerator temperatures for three months, far longer than the Pfizer vaccine that requires deep freezing for long-term storage.

“In countries where there is less health care infrastructure, it can be much better used at a very large scale,” Stoffels told Bloomberg. “Single dose, easy to use in the field are the main characteristics that make it different.”

The J&J product is made from a cold virus, called an adenovirus, that’s modified to make copies of the coronavirus’s spike protein.