The United States Food and Drug Administration (FDA) authorised Johnson & Johnson’s single-shot Covid-19 vaccine for emergency use.
The announcement arrived at a critical moment, as the steep decline in coronavirus cases in the US seemed to have plateaued.
J&J has pledged to provide the US with 100 million doses by the end of June. There are already 600 million doses from the two-shot vaccines made by Pfizer-BioNTech and Moderna.
The J&J vaccine, known as JNJ-78436735 or Ad26.COV2.S., has been developed by Janssen Pharmaceutica, a Belgium-based division of the company, in collaboration with Beth Israel Deaconess Medical Centre.
The vaccine is based on the SARS-CoV-2 virus’s genetic instructions for building the spike protein that it uses to enter human cells.
But unlike the Pfizer-BioNTech and Moderna vaccines, which store the instructions in single-stranded RNA, the J&J vaccine uses double-stranded DNA.
Unlike the Pfizer, Moderna, Oxford-AstraZeneca and even the Bharat Biotech (Covaxin) vaccine, the J&J vaccine is given as a single dose.
J&J began work on its coronavirus vaccine in January 2020, and received $456 million in assistance from the US government in March.