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The director of the Centers for Disease Control and Prevention (CDC), Rochelle Walensky, MD, signed off Sunday on an advisory panel’s unanimous endorsement of the newly approved single-dose COVID-19 vaccine from Janssen/Johnson & Johnson (J&J).
Her action clears the way to begin distributing the adenovirus vaccine across the United States for use in people aged 18 years and older.
Calling it a “milestone toward an end to the pandemic,” Walensky said in a prepared statement that this vaccine “has been shown to be safe and effective in preventing severe COVID-19 illness, hospitalization, and death. [It] is also another important tool in our toolbox to equitably vaccinate as many people as possible, as quickly as possible. As a one-dose vaccine, people do not have to return for a second dose to be protected.”
Twelve members of the CDC’s Advisory Committee on Immunization Practices (ACIP) voted unanimously in an emergency session to approve the use of the new vaccine from Janssen and J&J. The vaccine was authorized for emergency use on Saturday by the US Food and Drug Adminstration. One panel member recused himself because of a potential conflict of interest.
“In the midst of this tragedy, we do have some reason for optimism,” said Matthew Daley, MD, a pediatrician with Kaiser Permanente in Colorado who is a voting member of the ACIP.
“I just want to state explicitly how very grateful I am that we now have three very safe and highly effective vaccines,” he said. “If we use all supplies of all three vaccines, everyone essentially moves up on whatever prioritization list that they’re on.”
The new vaccine gives the United States an important new weapon against the SARS-CoV-2 virus. The first vaccines approved in the United States, from Pfizer and Moderna, need to be kept frozen. This new vaccine can be stored at conventional refrigeration temperatures for up to 3 months, making it accessible to a wider range of providers and healthcare settings — such as in doctors’ offices.
In clinical trials, the overall efficacy of the J&J vaccine against moderate to severe COVID-19 28 days post vaccination was 66%. It was even more efficacious — about 85% — at preventing severe disease and was 100% efficacious at preventing hospitalization and death.
In her presentation before the ACIP, Sara Oliver, MD, a member of the CDC’s Epidemic Intelligence Service, stressed that it was difficult to compare the efficacy of the J&J vaccine to that of the previous ones because it was tested at a different point in the pandemic and in different settings ― South Africa and Brazil, countries where infections and variants were rapidly spreading. In weighing the benefits and harms of the Janssen vaccine, Oliver said the committee felt the desired effects were large, whereas the undesirable effects were small.
“It’s clear they all provide a high level of protection against what’s most important, including hospitalization and death,” said Jeff Duchin, MD, the health officer for public health in Seattle and King County, Washington.
Most side effects of the vaccine were not serious. They included headache, fever that lasted about a day, and achy muscles.
In the past week, Janssen, the company that created the vaccine, said it had been notified of two serious allergic reactions to its vaccine. A 39-year-old woman developed a fever, swollen tongue, hives, and difficulty breathing a few hours after vaccination. She was taken to the hospital and was treated with hydrocortisone. A 40-year old woman developed fever, chills, and a drop in blood pressure approximately 10 minutes after getting her shot. Both of the women are in the South African arm of the trial.
Those events are still under investigation.
Allergic reactions to the COVID vaccines are extremely rare. It’s not yet known what causes them, but the CDC has warned that people who have been diagnosed with allergies to polyethylene glycol and polysorbate 80 not take the vaccines. The Janssen/J&J vaccine contains polysorbate 80.
Regulators are also keeping an eye on other potential red flags. In the clinical trials, more people in the vaccinated group experienced events caused by blood clots — such as strokes — than did people who received placebo. There were 15 of these events in the vaccine group, compared to 10 in the placebo group.
There were also more cases of tinnitus in the vaccinated group than in the placebo group. There were six cases in the vaccine group and none in the placebo group, but it’s not clear whether the tinnitus was caused by the vaccinations.
In a presentation to the ACIP, Macaya Douoguih, MD, head of clinical development and medical affairs at Janssen, said the company was poised to deliver enough doses of the vaccine to cover 20 million Americans by the end of March.
She said the company would begin trials of its vaccine in adolescents next week and would begin to study the vaccine in pregnant women in March or April.
They are also testing a two-dose regimen to see whether a second shot might boost efficacy and durability of the protection.