Issued on Saturday, the EUA authorizes the shot for adults aged 18+. It is the third COVID-19 vaccine to be given the green light in the US, and the first viral vector type (Pfizer and Moderna, both granted EUA in December, are mRNA vaccines).
“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. “With [this] authorization, we are adding another vaccine in our medical toolbox to fight this virus.”
It is also the first authorization for the J&J vaccine globally: which is already being delivered to health workers in South Africa under a Phase 3b trial program; and is currently being assessed for Conditional Marketing Authorisation in Europe. In the US, J&J plans to file for a Biologics License Application (BLA) later in 2021.
“This [EUA] milestone follows a year of incredible work by our dedicated teams and unprecedented collaboration with health leaders around the world – all of whom shared a goal of bringing a single-shot vaccine to the public,” said Alex Gorsky, Chairman and Chief Executive Officer at Johnson & Johnson.
Vaccine efficacy
The FDA drew on Phase 3 trial data: which showed the Ad26.COV2.S vaccine was 67% effective overall in preventing moderate to severe COVID-19 (In US-based trials, this was 74%). Additionally, the vaccine was approximately 77% effective in preventing severe/critical COVID-19 occurring at least 14 days after vaccination and 85% effective in preventing severe/critical COVID-19 occurring at least 28 days after vaccination.
An FDA summary published last week also showed there were no safety concerns about the vaccine.
The J&J vaccine differs from most other authorized vaccines in that is only requires a single shot: creating a logistical advantage and helping vaccinate more people more quickly.
Its Phase 3 trials also included a cohort in South Africa, allowing the company to determine the vaccine is 52% effective against the B.1.351 strain.
The vaccine can be stored at refrigerated temperatures for up to 3 months.
Viral vector tech
While AstraZeneca’s viral vector vaccine has been authorized in the UK, Europe and other jurisdictions; the J&J vaccine is the first of this type in the US.
It is manufactured using adenovirus type 26 (Ad26): which delivers a piece of the DNA used to make the “spike” protein of the SARS-CoV-2 virus.
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. 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.
The vaccine is based on Janssen’s Ad26 vector platform, which is already used with other vaccines (the Ad26.ZEBOV/MVA-BN-Filo Ebola vaccine was approved by the European Medicines Agency in July; while investigational vaccines are being developed against Zika, filovirus, HIV, HPV, malaria, and respiratory syncytial virus).
The vaccine is administered as a single intramuscular injection of 5×1010 vp.