J&J’s Covid-19 Vaccine Is Safe and Effective, FDA Says

The agency, in its review of J&J’s late-stage study testing the vaccine in about 44,000 volunteers in the U.S., South Africa and other countries, confirmed the vaccine worked safely by a number of measures, including against new variants.

The shot appeared to prevent severe disease. There were seven Covid-19 deaths among study subjects getting a placebo, compared with no deaths among those who got the vaccine. Likewise, fewer people who got the vaccine developed critical Covid-19 cases than volunteers on placebo did.

J&J’s vaccine “met the prespecified success criteria” for the study, the FDA said.

J&J released new information, in an analysis that the FDA posted along with its own, suggesting the vaccine might also help reduce asymptomatic spread of the coronavirus. The vaccine reduced infections that didn’t cause symptoms in study subjects, J&J said.

Public-health officials say that a vaccine that can block such infections will be critical to limit the spread of the coronavirus and bring the pandemic to an end. One of the reasons the virus has spread so widely is because of asymptomatic transmission.

A committee of outside medical specialists convenes Friday to evaluate the analyses by both the FDA and the company, as the panel did for the first two Covid-19 vaccines to be cleared for use.

The advisory committee is expected to recommend the FDA authorize the J&J vaccine, and the agency is expected to make its decision soon after.

The regulatory green light would bolster vaccination efforts just as health authorities pick up the pace to get people back to schools, offices and other establishments ahead of new strains that threaten to evade medicines.

Health authorities expect the initial supply of the J&J vaccine will help ease, though not eliminate, the frustration felt by people unable to sign up for shots because there aren’t enough doses available.

J&J has said it would deliver about 20 million doses for U.S. use by the end of March, which may be enough to boost the countrywide capacity for completed vaccinations by about 20%.

The two other Covid-19 vaccines authorized in the U.S. come from Moderna Inc. and from a partnership between Pfizer Inc. and Germany’s BioNTech SE. The companies have projected delivering enough of their two-dose vaccines by the end of March to immunize 100 million people.

Each of those vaccines requires two shots to confer their full benefit. The J&J vaccine involves only one shot, a factor that also may ease the logistics of delivering doses. The shot also doesn’t require ultracold temperatures, meaning that sites without expensive freezers can start vaccinations.

The late-stage study evaluating J&J’s vaccine primarily measured whether the vaccine prevented cases of Covid-19 that resulted in moderate to severe symptoms.

J&J said a preliminary analysis of a subset of study subjects suggested the vaccine was 65.5% effective in preventing infections that caused no symptoms. J&J cautioned, however, that more analysis is needed to confirm whether the vaccine prevents asymptomatic infections.

Generally, the vaccine proved to be effective protecting against moderate and severe Covid-19.

The vaccine’s efficacy was roughly comparable across most demographic subgroups in the study. However, it was only 42.3% protective in people 60 and over who had certain medical conditions such as diabetes and hypertension, J&J said.

The FDA found there were two Covid-19 hospitalizations starting 14 days in the vaccine group, versus 29 in the placebo group. There were no new hospitalizations after 28 days in people vaccinated, while in the placebo group there were 29.

In the U.S. alone, the vaccine was 72% effective, J&J said. The shot wasn’t as effective in South Africa alone, where a new and more transmissible variant of the virus has emerged.

J&J said, in an analysis that the FDA posted along with its own, the vaccine’s efficacy ranged from 52% to 64% from two weeks to a month after vaccination among South Africa trial subjects.

The company said its vaccine performed even better protecting against severe disease in South Africa, with the vaccine from 73.1% to 81.7% effective two weeks to a month after vaccination.

The vaccine’s efficacy was even higher in Brazil, where another variant has spread.

Several Covid-19 vaccine makers including Moderna and J&J have said they are working on modified shots that could prove more effective against new Covid-19 variants.

The Pfizer-BioNTech and Moderna vaccines recorded higher effectiveness rates in their late-stage trials than J&J’s vaccine. Those companies’ trial results, however, occurred largely before new variants are known to have emerged.

The FDA analysis and advisory-committee meeting are intended to reinforce public confidence in the vaccine, and the FDA’s evaluation would appear to do that.

The vaccine appeared generally safe. The most common side effects, J&J said, were headache, fatigue, muscle ache and injection-site pain. Most weren’t severe. There were no severe allergic reactions known as anaphylactic reactions in studies of its vaccine—something that has occurred rarely in those receiving the Pfizer and Moderna vaccines.

J&J said there were three non-Covid deaths among vaccine recipients in the study but none were considered related to the vaccine, while 16 people who had received a placebo died, some from non-Covid causes.

J&J said one vaccine recipient in the study experienced a condition called transverse sinus thrombosis, a type of blood clot in the brain, resulting in cerebral hemorrhage.

This serious event led to a pause in testing of J&J’s vaccine in October because researchers initially thought it was related to the vaccine. J&J said study investigators subsequently determined it was related to the patient’s pre-existing medical conditions and not the vaccine. The study resumed enrollment later in October.

The expected FDA action is known as an emergency-use authorization, a designation created by federal law to deal with situations like the current global pandemic.

It falls short of a full FDA approval. Yet the FDA has nevertheless required large clinical studies, as well as following study volunteers for a median of two months following vaccination.

J&J has said it expects to ship 100 million doses throughout the U.S. by late June and to supply more than one billion doses world-wide during 2021.

Pfizer and Moderna have committed to supplying enough doses by the end of July to vaccinate 300 million people in the U.S.

Write to Thomas M. Burton at [email protected] and Peter Loftus at [email protected]