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Home » Johnson and Johnson COVID-19 vaccine scientific facts

Johnson and Johnson COVID-19 vaccine scientific facts

Last updated on June 2nd, 2021 at 10:44 am

On 26 February 2020, the Johnson and Johnson (JNJ) COVID-19 vaccine underwent an FDA expert review, similar to the ones for the Pfizer and Moderna COVID-19 vaccines. The FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) voted unanimously in favor of the third vaccine in the USA to prevent COVID-19. This vote by the vaccine experts is the last step in advance of FDA clearance for an Emergency Use Authorization (EUA).

This article will review the key points about the Johnson and Johnson COVID-19 vaccine’s safety, effectiveness, ingredients, and other critical information. This scientific information should answer a lot of questions about the vaccine that will inevitably arise over the next few weeks.

This will be different than my myth debunking article (which will be constantly updated as the anti-vaxxers get going with their lies and disinformation), as this article will try to make sure that everyone is on the same page with what this vaccine is. 

johnson and johnson COVID-19 vaccine
Photo by Artem Podrez on

What is this FDA expert review?

Almost all of the information in this article will come from the Johnson and Johnson COVID-19 vaccine documents that were submitted for review by the Vaccines and Related Biological Products Advisory Committee (VRBPAC) in advance of an emergency use authorization (EUA) once the FDA reviews and approves the findings. I read through most of the material to save you all time during this holiday season (so please like this article and share it across the planet).

There is a myth pushed by the anti-vaccine crowd that the FDA summarily approves vaccines without even a cursory review. They think that the FDA trusts anything Big Pharma submits to them without thinking. That couldn’t be further from the truth.

Every drug, including the JNJ COVID-19 vaccine, is almost always reviewed by an expert committee of scientists alongside career FDA scientists. These are thorough, scientific, and open.

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 may not attend ) including one vaccine industry scientist (not from JNJ) and one consume representative. All of the voting members of VRBPAC are scientists, statisticians, physicians, and FDA experts.

Because it will be a thing, Dr. Paul Offit, MD, who has been designated a demon Big Pharma shill by anti-vaxxers, is a member of the committee. Dr. Offit is one of the world’s experts on vaccines, who developed one of the rotavirus vaccines that have saved hundreds of thousands of lives across the world every year. 

According to the FDA, the committee is charged with:

The Committee reviews and evaluates data concerning the safety, effectiveness, and appropriate use of vaccines and related biological products which are intended for use in the prevention, treatment, or diagnosis of human diseases, and, as required, any other products for which the Food and Drug Administration has regulatory responsibility. The Committee also considers the quality and relevance of FDA’s research program which provides scientific support for the regulation of these products and makes appropriate recommendations to the Commissioner of Food and Drugs.

The Committee shall consist of a core of 15 voting members including the Chair. Members and the Chair are selected by the Commissioner or designee from among authorities knowledgeable in the fields of immunology, molecular biology, rDNA, virology; bacteriology, epidemiology or biostatistics, vaccine policy, vaccine safety science, federal immunization activities, vaccine development including translational and clinical evaluation programs, allergy, preventive medicine, infectious diseases, pediatrics, microbiology, and biochemistry.

These experts are not industry shills. They are some of the leading experts in all fields of vaccinology, not amateurs with a 15-minute education on vaccines. VRBPAC is a dignified committee that puts scientific evidence above all else.

What is the Johnson and Johnson COVID-19 vaccine technology?

The JNJ COVID-19 vaccine is very different than the Pfizer and Moderna mRNA vaccines. But it still induces an adaptive immune memory response to the S-protein of the SARS-CoV-2 virus that causes COVID-19.

The JNJ COVID-19 vaccine, known as the JNJ-78436735, utilizes a recombined adenovirus vector, human Ad26.COV2.S., which expresses the S-subunit of the SARS-CoV-2 virus to induce an immune response. Basically, the adenovirus vector “carries” the genes for the S-subunit to the cell which will reproduce the protein, then inducing the immune response.

Adenovirus-based vaccines have been investigated for several decades. In fact, JNJ received approval for an Ebola adenovirus vaccine in July 2020, so the technology did not come out of anywhere just for COVID-19. However, like the mRNA vaccines, these adenovirus vaccines, also used by AstraZeneca, can be quickly developed to deliver the most important antigen on the SARS-CoV-2 virus, which is the S-protein.

There is an advantage to adenovirus-based vaccines – they are much less fragile than mRNA vaccines because they are based on DNA which is more rugged than RNA.

Once the Johnson and Johnson COVID-19 vaccine is injected into the arm, the adenoviruses enter cells and moves to the nucleus, where the cell’s genes (DNA) are located.

The adenovirus then injects its DNA into the nucleus. The adenovirus is engineered so it can’t make copies of itself, but the gene for the coronavirus spike protein can be read by the cell and copied into a molecule called messenger RNA, or mRNA.

At this point, it is similar to the mRNA vaccines.

Normally, during the process called transcription, RNA polymerase makes a copy of a gene from its DNA to a corresponding mRNA fragment whenever required by the cell. In other words, the mRNA sequences in the cell usually correspond directly to the DNA sequences in our genes. These mRNA sequences “carry” that genetic message to a ribosome for translation, where tRNA triplets, which code for one amino acid, attach to the appropriate mRNA triplet, adding one amino acid to the protein chain. 

As in DNA, genetic information in mRNA is contained in the sequence of nucleotides, which are arranged into codons consisting of three ribonucleotides each. Each codon codes for a specific amino acid, except the stop codons, which terminate protein synthesis.

Like with mRNA vaccines, the adenovirus does not change the genetic code of any of the 50 trillion cells that are in a human. All that happens is that the adenovirus injects DNA that is coded for the S-protein and the cell produces mRNA from that DNA that then causes the ribosomes to produce the S-protein.

Those S-proteins migrate to the surface of the cell which is then recognized by the immune system as foreign invaders. The immune system then remembers those antigens – when the actual SARS-CoV-2 virus attacks, the immune system is ready to attack.

The Johnson and Johnson COVID-19 vaccine also has one additional advantage over the mRNA vaccines – the adenovirus itself provokes the immune system to activate immune cells that are nearby. This leads to the immune system reacting more strongly to the spike proteins.

Johnson and Johnson COVID-19 vaccine facts

I am going to review the facts about the JNJ COVID-19 vaccine one-by-one. Most of this information will end up in a vaccine package insert, so knowing this information now will help to deal with the inevitable anti-vaccine disinformation campaign.

Basically, I will delve into the following key facts:

  1. Ingredients
  2. Dosage
  3. Clinical trial demographics and included comorbidities
  4. Adverse events
  5. Effectiveness
  6. Other information

So let’s start.


As any of us who have had to deal with anti-vaccine misinformation, attacking the ingredients is part of the standard operations. Here are the ingredients, and an explanation of what it is and why they are in the vaccine:

  • Adenovirus. Replication-incompetent recombinant adenovirus type 26 (Ad26) vector expressing the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) spike (S) protein in a stabilized conformation
  • Buffers. citric acid monohydrate, trisodium citrate dihydrate, ethanol, 2-hydroxypropyl-β-cyclodextrin (HBCD), polysorbate 80, sodium chloride, sodium hydroxide, and hydrochloric acid. These compounds are in tiny quantities (nanograms) and are buffers that stabilize the vaccine.
  • Preservatives. None, period. So the first person who says there is thiomersal or something else in here can go take a time-out in the corner. 

None of these ingredients will cause any issue with any human at the incredibly low concentrations found in the vaccine. Sure, you might get ill or die if you consumed 1000 grams of any of these “chemicals”, but this vaccine includes less than 100 µg (1-millionth of a gram) of these compounds. And no, a little isn’t going to hurt you, because that’s not how toxicology works – the dose makes the poison


The JNJ vaccine is shipped as a refrigerated suspension (stored at 2°C to 8°C (36°F
to 46°F, for those of you who hate the metric system) in a multi-dose vial containing 5 doses (0.5 mL each). The vials should be protected from light. Unpunctured vials may be stored between 9°C to 25°C (47°F to 77°F) for up to 12 hours.

These are normal refrigerator temperatures which are substantially better than the ultra-cold storage required for the Pfizer vaccine.

Finally, the vaccine requires just one dose to elicit the immune response. The Pfizer and Moderna vaccines were approved for 2 doses.

Clinical trial demographics and included comorbidities

Study 3001 is an ongoing randomized, double-blind, placebo-controlled study to evaluate the efficacy, safety, and immunogenicity of Ad26.COV2.S administered as a single dose in adults ≥18 years of age. A target of 40,000 adults was to be randomized 1:1 to receive intramuscular injections of either vaccine or placebo. At least 30% of the total study population was to consist of participants ≥60 years of age, and enrollment of participants 18 to 40 years of age was limited to approximately 20% of the total study population.

Planned and completed clinical trials for the JNJ AD26.COV2.S COVID-19 vaccine.

The co-primary endpoints were the efficacy of a single dose of vaccine to prevent centrally
confirmed, moderate to severe/critical COVID-19 occurring

  1. at least 14 days after vaccination and
  2. at least 28 days after vaccination in study participants without evidence of prior SARSCoV-2 infection at baseline

Adverse events

The most common solicited adverse reactions were considered minor. Vaccination site pain was reported by 1,634 (48.7%) participants in the Ad26.COV2.S group, vaccination site erythema and swelling were reported in <8% of participants in the Ad26.COV2.S group.

Demographic makeup of vaccinated and placebo groups.
Minor adverse events were extremely rare in the vaccinated group of about 20,000 individuals.
Johnson and Johnson COVID-19 vaccine
Serious adverse events.

Serious adverse events were observed in about 0.4% of the vaccinated group. However, the same number of adverse events, 0.4%, in the placebo group. This is observed because these events happen randomly in all populations, vaccinated or not. Thus, some number of people will have a cardiovascular event irrespective of vaccine status, so it’s almost impossible to establish causality because correlation does not exist between these serious adverse events and vaccine status. According to the filing documents, “there were no notable patterns or numerical imbalances suggesting a causal relationship to the vaccine or safety signals identified.”

In addition, severe allergic reactions (anaphylaxis) have not been reported in JNJ Ad26.COV2.S clinical studies and have not been identified as a safety issue for these vaccines.

Because it is always of interest to those who watch clinical trials there were 19 deaths reported in the clinical trial. However, 16 of those were in the placebo group. Six of the 16 deaths in the placebo group were confirmed (by positive RT-PCR test) to be associated with COVID-19.

None of the deaths were actually linked to the vaccine.

Johnson and Johnson COVID-19 vaccine


Probably the most important issue with any new vaccine is its effectiveness. According to the data, the vaccine efficacy (VE) of the Johnson and Johnson COVID-19 vaccine against severe/critical COVID-19 was 73.1% at least 14 days after vaccination and increased to 81.7% at least 28 days after vaccination. An effect was also seen on mortality, since all COVID-19-associated deaths in the study, all in the placebo group, occurred in participants from South Africa. Vaccine efficacy against moderate to severe/critical COVID-19 was 52.0% at least 14 days and 64.0% at least 28 days after vaccination. 

For the immunogenicity results 

Johnson and Johnson COVID-19 vaccine

Although the effectiveness of this vaccine may appear lower than the 95% reported for the mRNA vaccines, they are still within the statistical range of them. For example, individuals without comorbidities exhibited vaccine effectiveness of nearly 90%. In fact, the only group that showed very low effectiveness were those ≥60 years old with comorbidities.

This group is problematic with many vaccines, including the flu vaccine. In fact, there is a senior flu vaccine that has nearly a double dose to boost the immune system.

However, overall the vaccine showed 100% effectiveness against death and 86% effectiveness against the most severe forms of the disease. Although it may appear at the surface that the vaccine is less effective than the mRNA vaccines from Moderna and Pfizer, the JNJ COVID-19 vaccine is within the statistical range of them. It should not be dismissed as a viable vaccine.

Furthermore, it is difficult to compare one clinical trial to another to determine whether one vaccine is more effective than another. The Moderna and Pfizer COVID-19 vaccines were in clinical trials during the earliest part of the pandemic, whereas the JNJ vaccine underwent clinical trials during the later part of the pandemic where there were more virulent variants of the disease out in the world.

Other Information

Phase 3 clinical trials are not the endpoint for research on any vaccine, including vaccines. JNJ is planning long-term monitoring of the vaccine, watching for any safety signals and changes in vaccine effectiveness over time from the CDC and other groups. We will probably see many peer-reviewed published articles appearing every month with new data from this vaccine.

JNJ is also planning to do three additional actions long-term with the vaccine:

  1. Active follow-up for safety. JNJ intends to conduct retrospective analyses of medical and pharmacy claims to analyze observed vs predicted rates of adverse events.
  2. Real-world effectiveness study. JNJ will also continue to monitor effectiveness over time.


In case you do not want to read all the details above, here is a summary of the Johnson and Johnson adenovirus COVID-19 vaccine:

  1. Ingredients – nothing remarkable
  2. Dosage – one dose
  3. Storage conditions – refrigerator
  4. Clinical trial demographics and included comorbidities – 40,000 individuals roughly divided equally between placebo and vaccine groups. The study was performed across the world, was balanced demographically, and included numerous comorbidities.
  5. Adverse events – minor adverse events were expected as with most vaccines. Serious adverse events and deaths were not vaccine-related, and the incidence was approximately equal in both vaccine and placebo groups.
  6. Effectiveness – the vaccine reduces the risk of COVID-19 by 81.7% compared to placebo for severe COVID-19 disease.
  7. JNJ will continue to monitor the safety and effectiveness of the vaccine over the next few years and will perform additional studies to include pregnant women and to determine long-term effectiveness.


The Johnson and Johnson vaccine was actually developed by a Belgian subsidiary of JNJ, Janssen Pharmaceuticals. Most news outlets refer to the vaccine as from Johnson and Johnson or JNJ, but a few people call it a Janssen vaccine. Dr. Anthony Fauci usually refers to it as the Janssen vaccine.


  • Chawla T, Khanna N, Swaminathan S. Adenovirus-vectored vaccines. Expert Opin Ther Pat. 2008 Mar;18(3):293-307. doi: 10.1517/13543776.18.3.293. PMID: 20144086.


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