US closer to its 3rd COVID vaccine — and this one only needs one shot. What to know

Katie Camero
·4 min read

The U.S. Food and Drug Administration released a report on Wednesday that says the one-dose Johnson & Johnson COVID-19 vaccine has a “favorable safety profile with no specific safety concerns,” clearing the way for emergency use authorization.

A committee of scientific experts will meet on Friday to discuss the vaccine’s safety and efficacy, as it did for the authorized Pfizer-BioNTech and Moderna shots. If the group decides to recommend the Johnson & Johnson vaccine for FDA authorization, the shot will become the nation’s third COVID-19 vaccine, joining the fight against the pandemic spurred by more contagious variants.

The vaccine requires one dose and can be stored for three months at normal temperatures, easing distribution efforts and accelerating vaccination rates compared to the two-dose Pfizer and Moderna shots that require ultra cold refrigeration, which some regions lack access to.

Dr. Paul Stoffels, chief scientific officer for Johnson & Johnson, said in January that the results “represent a promising moment.

“The potential to significantly reduce the burden of severe disease, by providing an effective and well-tolerated vaccine with just one immunization, is a critical component of the global public health response.”

The Phase 3 clinical trial, which included nearly 44,000 participants 18 years and older, found that the Johnson & Johnson vaccine was overall 66% effective at preventing moderate to severe COVID-19 in the lab at least 28 days after getting jabbed.

In the U.S., the vaccine was about 72% effective at preventing moderate to severe COVID-19. However, that percentage dropped to 64% in South Africa, where a more contagious coronavirus variant has dominated all others. Still, the vaccine offered “similarly high” protection in both regions, including Brazil, where another more transmissible variant has emerged.

Both the Pfizer and Moderna vaccines have efficacy rates of about 95%.

There were no deaths among those who received the vaccine; seven people who got a placebo died from COVID-19.

Johnson & Johnson had said it plans on shipping vaccines “immediately upon emergency use authorization, and deliver enough single-doses by the end of March to enable the vaccination of more than 20 million Americans.”

Side effects of the Johnson & Johnson vaccine

Immediate reactions to the shot 30 minutes post vaccination were “infrequent,” occurring in 0.02% of participants, while there were no reports of anaphylaxis, or severe allergic reactions, immediately after getting jabbed.

The most common side effects were pain around the injection site (49%), headache (39%), fatigue (38%) and muscle aches (33%) — similar reactions but slightly less frequent than those of the Pfizer and Moderna shots. They were less common in adults older than 60 and generally resolved one to two days after vaccination.

Skin rashes, blood clots and tinnitus were reported in five, 15 and six vaccine recipients, respectively, within seven days after getting the shot. The company said these events are “possibly related to the vaccine,” but “data at this time are insufficient to determine a causal relationship between these events and the vaccine.”

There were “no specific safety concerns” among groups by age, race, ethnicity, medical comorbidities or prior coronavirus infection, according to the report.

Participants who were pregnant or were planning on becoming pregnant within three months of getting the vaccine were excluded from the study. Four individuals reported they became pregnant after receiving the shot; the company said it is collecting data on them.

The company submitted a request for emergency use authorization on Feb. 4. The FDA can authorize the vaccine as early as this weekend, The Wall Street Journal reported.

How the Johnson & Johnson vaccine works

The Johnson & Johnson is a viral vector vaccine.

It works by delivering a modified version of a different, harmless virus (not the novel coronavirus) that carries instructions on how to make the spike protein the coronavirus uses to infect people into our cells, according to the Centers for Disease Control and Prevention.

Our cells then display the spike protein on its surface like a trophy on a pedestal, which the immune system doesn’t recognize. This triggers the production of coronavirus-fighting antibodies and primes the body to protect itself against the pathogen if it comes into contact with it.

This method is different from how the Pfizer and Moderna shots work. They insert mRNA — a molecule already found in the body — that carries directions that teach our cells to make copies of the spike proteins, sparking the creation of antibodies.