On Saturday, the US Food and Drug Association (FDA) granted an Emergency Use Authorization (EUA) to a COVID-19 vaccine by Janssen Biotech Inc., a Janssen Pharmaceutical Company of Johnson & Johnson. This is the third vaccine to be granted EUA in the US after those manufactured by Pfizer-BioNtech and Moderna respectively.

“The authorization of this vaccine expands the availability of vaccines, the best medical prevention method for COVID-19, to help us in the fight against this pandemic, which has claimed over half a million lives in the United States,” said Acting FDA Commissioner Janet Woodcock, M.D.

In a press release, the FDA says that it can “assure the public and medical community that it has conducted a thorough evaluation of the available safety, effectiveness and manufacturing quality information.”

“After a thorough analysis of the data, the FDA’s scientists and physicians have determined that the vaccine meets the FDA’s expectations for safety and effectiveness appropriate for the authorization of a vaccine for emergency use,” said Peter Marks, M.D., Ph.D., director of the FDA’s Center for Biologics Evaluation and Research.

The Janssen COVID-19 vaccine

EUA vs Approval

The FDA clarifies the distinction saying, “The issuance of an EUA is different than an FDA approval (licensure) of a vaccine, in that a vaccine available under an EUA is not approved. In determining whether to issue an EUA for a product, the FDA evaluates the available evidence to determine whether the product may be effective and also assesses any known or potential risks and any known or potential benefits. If the product meets the effectiveness standard and the benefit-risk assessment is favorable, the product is made available during the emergency.” 

How does it work?

The Janssen vaccine is a single dose vaccine. Explaining how the vaccine works, the FDA says, “The Janssen COVID-19 Vaccine is manufactured using a specific type of virus called adenovirus type 26 (Ad26). The vaccine uses Ad26 to deliver a piece of the DNA, or genetic material, that is used to make the distinctive “spike” protein of the SARS-CoV-2 virus. While adenoviruses are a group of viruses that are relatively common, Ad26, which can cause cold symptoms and pink eye, has been modified for the vaccine so that it cannot replicate in the human body to cause illness. After a person receives this vaccine, the body can temporarily make the spike protein, which does not cause disease, but triggers the immune system to learn to react defensively, producing an immune response against SARS-CoV-2.”

Safety and efficacy

The FDA explains the detailed process undertaken to evaluate the safety and efficacy saying, “The available safety data to support the EUA include an analysis of 43,783 participants enrolled in an ongoing randomized, placebo-controlled study being conducted in South Africa, certain countries in South America, Mexico, and the U.S. The participants, 21,895 of whom received the vaccine and 21,888 of whom received saline placebo, were followed for a median of eight weeks after vaccination.” About side effects of the Janssen vaccine, the FDA says, “The most commonly reported side effects were pain at the injection site, headache, fatigue, muscle aches and nausea. Most of these side effects were mild to moderate in severity and lasted 1-2 days.”

*Feature Image: Army Col. Sean Dooley, a doctor at Walter Reed National Military Medical Center, receives a COVID-19 vaccination, Walter Reed National Military Medical Center, Bethesda, Md., Dec. 14, 2020. (DoD photo by Lisa Ferdinando) via Wikimedia Commons.