A Guide to Johnson & Johnson’s COVID-19 Vaccine
The Johnson & Johnson vaccine is the third COVID-19 vaccine to be authorized by the Food and Drug Administration. Here, we give a rundown of basic facts about the vaccine and an overview of how it works.
Quick Summary
Vaccine name: Ad26.COV2.S
Design type: Adenovirus viral vector
Dose number: 1 dose
Efficacy: Overall, 66.1% efficacy in preventing moderate to severe COVID-19 in adults 28 days or more after vaccination, but efficacy was higher in the U.S. population (72% efficacy in preventing moderate to severe COVID-19 and 85.9% efficacy in preventing severe or critical COVID-19) than in South Africa (64% and 81.7% efficacy in preventing moderate to severe or severe/critical disease, respectively), where a new strain of coronavirus emerged.
Safety: No serious safety concerns reported. The shot, however, did elicit temporary side effects in some recipients, including pain at the injection site, headache, fatigue, and muscle pain or ache.
Expected dose availability: Nearly 4 million available immediately in the U.S. upon FDA authorization; 20 million by the end of March and 100 million by the end of June.
Expected timeline: On Feb. 27, the FDA authorized the vaccine
