Share on Pinterest
Phase 3 data on Johnson & Johnson’s COVID-19 vaccine was released Friday. MARK RALSTON/Getty Images
  • Interim results from Johnson & Johnson phase 3 trials show that its vaccine offers protection against moderate to severe COVID-19.
  • The company is expected to seek emergency authorization next month.
  • The vaccine may be released as soon as February.

All data and statistics are based on publicly available data at the time of publication. Some information may be out of date. Visit our coronavirus hub and follow our live updates page for the most recent information on the COVID-19 pandemic.

Johnson & Johnson said Friday, Jan. 29, that its single-dose coronavirus vaccine provided strong protection against moderate to severe COVID-19, although it appears to have a lower effectiveness against a new coronavirus variant first identified in South Africa.

Preliminary results released by the company show that the vaccine had an overall effectiveness of 66 percent against moderate to severe disease 28 days after vaccination.

Effectiveness is a measure of how well a vaccine works within the controlled environment of a clinical trial. Real-world effectiveness may be lower.

Effectiveness was similar for all age groups, including those 60 years and older.

However, it varied among regions: 72 percent in the United States, 66 percent in Latin America, and 57 percent in South Africa.

The company said nearly all of the COVID-19 cases in South Africa were due to the coronavirus variant known as B.1.351, which spreads more easily.

The vaccine also had an effectiveness of 85 percent against severe disease in all regions studied 28 days after vaccination.

The effectiveness of the vaccine against severe disease improved over time, with no severe cases seen after 49 days in people who were vaccinated.

In addition, the vaccine offered complete protection against hospitalization and death due to COVID-19 in all regions studied.

Although the overall effectiveness of the Johnson & Johnson vaccine falls below that of the two vaccines already approved for emergency use in the United States — Pfizer-BioNTech and Moderna-NIAID — it still exceeds the 50 percent efficacy threshold set by the Food and Drug Administration (FDA) for coronavirus vaccines.

Angela Rasmussen, PhD, a virologist at the Georgetown University Center for Global Health, Science and Security, said on Twitter that even with the Johnson & Johnson vaccine’s lower effectiveness, it’s still an important development.

“While efficacy varied by region, keeping people out of the hospital everywhere will save lives, which is what this is all about,” she wrote.

Hospitals that are overwhelmed with a surging number of COVID-19 patients have trouble not only taking care of COVID-19 patients, but also providing other urgent and routine care.

It’s difficult to directly compare the vaccines because the Pfizer-BioNTech and Moderna-NIAID clinical trials looked at how well their vaccines prevented any symptomatic coronavirus infection, which also included mild cases.

The Johnson & Johnson study looked only at protection against moderate or severe cases.

Dr. Bruce Y. Lee, executive director of the Public Health Computational and Operations Research (PHICOR) group and professor of health policy and management at CUNY Graduate School of Public Health and Health Policy, said the Johnson & Johnson vaccine has some advantages over the ones already approved.

“With a one-dose vaccine, you would only need to produce and distribute half as many doses, which could alleviate bottlenecks in the supply chain,” he said. “Also, having people return for a second dose is a logistical management challenge.”

The Johnson & Johnson vaccine also has less demanding storage requirements. The company said the vaccine can be stored for up to 2 years in a standard freezer, and at least 3 months in a refrigerator.

Both the Pfizer-BioNTech and Moderna-NIAID vaccines have to be stored in special freezers until they’re thawed just prior to use.

Johnson & Johnson’s results also suggest that the B.1.351 variant appears to evade the protection offered by the company’s vaccine.

Vaccine maker Novavax saw similar concerning signs. The company released preliminary results from its phase 3 trial on Thursday, Jan. 28, showing that its vaccine had an effectiveness of 90 percent in the United Kingdom, according to STAT News.

But the effectiveness dropped to 49 percent in South Africa, where B.1.351 is widely present.

The Centers for Disease Control and Prevention (CDC) said Thursday, Jan. 28, that the first U.S. cases of B.1.351 have been detected in South Carolina.

Dr. Anthony Fauci, the government’s top infectious disease expert, said Friday, Jan. 29, during a COVID-19 press briefing at the White House that the lower efficacy of the Johnson & Johnson vaccine in South Africa is a “wake-up call.”

However, he added that vaccinating as many people as we can, as quickly as possible — even if the vaccine has a lower efficacy — can help keep new variants from emerging.

“Viruses cannot mutate if they don’t replicate,” Fauci said. “And that’s the reason to continue to do what we’re doing.”

The Johnson & Johnson results are from an interim analysis of its phase 3 clinical trial. The study included 43,783 volunteers 18 and older, with 468 symptomatic cases of COVID-19 occurring during the study.

The vaccine uses a common cold virus known as an adenovirus to deliver the genetic instructions for the coronavirus’ spike protein to the cells. When the cells make the protein, it trains the immune system to recognize and attack the coronavirus.

The coronavirus vaccine developed by Oxford University and AstraZeneca uses a similar technology.

Both the Pfizer-BioNTech and Moderna-NIAID vaccines use mRNA technology to deliver the genetic instructions for the spike protein to the cells.

Johnson & Johnson said its single-dose vaccine was “generally well-tolerated” and there were no “significant safety concerns” identified by the study’s Data and Safety Monitoring Board (DSMB).

Nine percent of people who received the vaccine had a fever afterwards, with 0.2 percent having a fever of more than 104°F, according to the interim results. No severe allergic reactions occurred.

These interim results aren’t the end of the research for this vaccine.

“There are still many unanswered questions,” Lee said, “such as the duration of protection or the degree to which the vaccines prevent infection and [viral] shedding.”

Johnson & Johnson plans to apply for emergency approval from the FDA in early February, and expects to be able to ship doses immediately after the vaccine is authorized.

The company has a contract with the United States to provide 100 million doses by the end of June, but only 7 million may be available to ship immediately, according to The New York Times.

If the Johnson & Johnson vaccine is approved, the country will have three different vaccines to choose from. But with one having a lower effectiveness, should people hold out for an mRNA vaccine?

It depends.

Lee and his colleagues published a study recently in the American Journal of Preventive Medicine that found that waiting for a higher efficacy vaccine doesn’t make sense — at least for the country as a whole.

“Our results suggest that, from a population standpoint, it’s better for people to get the first vaccine available, even if the efficacy for the vaccine is lower,” he said, “because having some protection is better than nothing.”

However, what individuals decide to do will depend on which vaccines are available in their area and how long they’re willing to wait for their preferred vaccine.

A year ago, a vaccine with 90 percent efficacy seemed unlikely, especially since the effectiveness of the seasonal flu vaccine varies from 40 to 60 percent.

And even 72 percent efficacy is better than nothing.

“Any of these vaccines, including J&J’s, are better than current flu vaccines are against flu,” said Dr. Reynold A. Panettieri, Jr., a professor at the Rutgers Robert Wood Johnson Medical School and director of the Rutgers Institute for Translational Medicine and Science.

“Further, any COVID-19 vaccine will likely diminish COVID-19 health consequences compared with no vaccine,” he said.