Pharmaceutical giant Johnson and Johnson (JNJ) has submitted an application for an emergency use authorization (EUA) for its COVID-19 vaccine. In phase 3 clinical trials, results showed that it was effective against the illness, and it was especially robust in preventing severe cases of COVID-19 along with death.
The COVID-19 vaccine, which was developed by JNJ subsidiary Janssen Biotech, will be reviewed by an FDA advisory committee on 26 February 2021. If that review goes well, the FDA Commissioner could issue the EUA within a few days.
JNJ COVID-19 vaccine
The new JNJ COVID-19 vaccine utilizes a live recombined adenovirus vector, human Ad 26, that expresses the S-subunit of the SARS-CoV-2 virus to induce an immune response. These types of vaccines use the adenovirus, which cannot cause diseases, to transport some of the pathogen’s genes (in this case SARS-CoV-2) into the body.
These adenoviruses express the key antigens of the pathogen, for example the S-protein, to stimulate the immune system to attack and destroy the SARS-CoV-2 virus. This is similar to the rationale behind the Pfizer and Moderna mRNA vaccines, which induce the body to produce the antigens to stimulate the immune response.
Adenoviruses are a group of viruses that cause the common cold, so they make good vectors to carry genetic code into the body. The JNJ-Janssen adenovirus vector Ad26.COV2.S. has been genetically modified so that it can no longer replicate in humans – it just carries the S-protein into the body.
The current hepatitis B vaccine uses a similar technology – the hepatitis B surface antigen is produced in genetically-modified yeast because the hepatitis B virus cannot be grown in vitro.
The emergency use authorization process
As we saw with the Pfizer and Moderna vaccines, the new JNJ COVID-19 vaccine will be reviewed by the Vaccines and Related Biological Products Advisory Committee (VRBPAC) in advance of an emergency use authorization (EUA).
Every vaccine, including the JNJ COVID-19 vaccine, is nearly always reviewed by an expert committee of scientists alongside career FDA scientists before approval, including EUAs. The reviews are always deliberative, thorough, and careful.
For vaccines, the Vaccines and Related Biological Products Advisory Committee, also known as VRBPAC, are made up of experts in vaccines, public health, and statistics. There are around 30 individuals on the committee (although several did not attend nor participated) including one vaccine industry expert (a clinical physician-scientist, not some executive) and one consumer representative, in this case, a respected attorney who concentrates on healthcare issues.
After the review, the members of VRBPAC vote on whether or not to approve the vaccine for the EUA which will also include indications and contraindications (if any) for its use in the EUA. Once VRBPAC completes its review, the information is sent to the FDA commissioner for final review and approval, if warranted. A similar process for EUAs exists with other drug regulatory agencies.
Information about the JNJ COVID-19 vaccine
The phase 3 study, called ENSEMBLE, is a randomized, double-blind, placebo-controlled clinical trial of adults 18-years-old and older. The study was designed to evaluate the safety and effectiveness of the JNJ COVID-19 vaccine against both moderate and severe COVID-19 disease. The trial assessed the efficacy at day 14 and 28 as primary endpoints (although, like the Moderna and Pfizer clinical trials, data will continue to be accumulated over several years).
The trial was conducted in eight countries and included a diverse demographic population. It included 43,783 participants and accrued 468 symptomatic cases of COVID-19.
JNJ stated that its vaccine was 66% effective in preventing moderate to severe COVID-19 illness, which was lower than the approximately 95% effectiveness shown in the Pfizer and Moderna phase 3 clinical trials. However, the vaccine was approximately 85% effective in preventing severe cases of the disease. There were no hospitalizations or deaths among people who received the vaccine.
Part of the clinical trial was done in South Africa, where one of the new variants of the disease has arisen. Although data from that part of the trial has been made available, once it is, we will have better information as to how this vaccine prevents that new variant.
The JNJ COVID-19 vaccine has significant advantages over the Moderna and Pfizer vaccines – it can be stored at refrigerator temperatures (2-8ºC) for several months. More importantly, it only requires one shot as opposed to two that are necessary for the other vaccines.
Once all of the documents are submitted and made public for the JNJ COVID-19 vaccine, I will review them and post some of the more important details about the vaccine. We should have more information about the clinical trials, ingredients, and other information.
This is an exciting time to be following vaccines, so stay tuned!
[wp_ad_camp_5]
