An Overview of the Johnson & Johnson COVID-19 Vaccine

The Johnson & Johnson vaccine against the coronavirus disease 2019 (COVID-19) may not be in advanced stages of development yet like some of its competitors, but the company is moving forward with positive results and expects to seek emergency use authorization from the U.S. Food and Drug Administration (FDA) in early 2021.

The company is working with its pharmaceutical arm Janssen to develop the vaccine under the project names Ensemble and Ensemble 2. The company enrolled participants for its late-stage trials in December, and will test its vaccine with two different doses.

J&J covid

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How It Works

Johnson & Johnson's vaccine is being studied as a single- and two-dose adenovirus-based vaccine. It is an experimental viral vector vaccine that uses a weakened live pathogen (adenovirus) as the delivery method (vector) for transporting a recombinant vaccine for COVID-19. 

Recombinant vaccines use a small piece of genetic material from the virus to trigger an immune response. This genetic material for COVID-19 does not replicate in the body. A specific piece of the virus can be targeted, and recombinant vaccines are common and generally safe to use in a large population of people—even those with chronic health problems or who are immunocompromised.

There can be some drawbacks to recombinant vaccines. One example is that booster shots may be required over time. Examples of recombinant vaccines are pneumococcal vaccines and vaccines for meningococcal disease.

The science behind recombinant adenoviral vector vaccines has been around for a long time, but the only commercially available adenovirus-based vaccine is a rabies vaccine for animals. Adenovirus-based vaccines may also pose some problems in that the adenovirus is so common that the vaccine may not be as effective once booster doses are given, or that some people may already have immunity to the virus used in the vaccine.

How Effective Is It?

Early results show that a single dose of the Johnson & Johnson vaccine could induce 97% of study participants to make antibodies that effectively neutralized the virus in the laboratory, but clinical studies to see how well the vaccine actually prevents disease are awaited. Additional information on the effectiveness of the vaccine is expected in early 2021.

When Will It Be Available? 

The Johnson & Johnson vaccine is still being studied in clinical trials, but the company anticipates that the results will be published in early 2021. The trial was temporarily delayed for an unexplained illness, although no specific details were provided about what happened due to patient privacy. Regulators have since determined the event was not related to the vaccine and the trial was safe to resume.

The company hasn't announced a release date or price estimates yet, but the company is already taking reservations for orders of the vaccine if approved. Johnson & Johnson has a contract with the U.S. government for 100 million doses and the option to purchase an additional 200 million doses if the vaccine receives emergency use authorization.

The Centers for Disease Control and Prevention (CDC) is leading vaccination efforts, and all orders of COVID-19 vaccines, regardless of the manufacturer, will go through the agency. CDC is overseeing the distribution of vaccines, too.

CDC’s Advisory Committee on Immunization Practices (ACIP) has made recommendations on how to prioritize vaccine supplies. Healthcare workers and people living in long-term care facilities are the first to receive the vaccines, the quantity of which will be limited at first. The next priority groups are frontline essential workers, such as first responders, and people ages 75 and older followed by people ages 65 and older and people with high-risk medical conditions.

According to the CDC, there are more than 18 million healthcare workers in the United States and about 1.3 million Americans living in long-term care facilities. Each of these people would need to receive two doses of the vaccines authorized for emergency use. If Johnson & Johnson's vaccine is shown to be effective in a single dose, it would be the first vaccine candidate that may be given in just one dose.

The CDC estimated that it will take several months before the supply of vaccines catches up to the demand. Guidance on who will receive the vaccine and when will be updated as supplies become available.

The United States alone has a population of about 330 million—meaning nearly 700 million vaccine doses will be needed to vaccinate all of America if other vaccines follow a two-vaccine dose.

Although little information is available on the specifics of when everyone will receive the vaccine and where they can get it, state and local health departments will be coordinating efforts to distribute doses of the vaccines as they become available. The vaccine should be available both in physician offices and retail locations like pharmacies that administer other vaccines.

How Much Will a COVID-19 Vaccine Cost?

Once the vaccine is available, any doses purchased by the U.S. government will be free to its citizens. While the vaccine itself is free, the facility or agency that offers the vaccine may charge a fee for administration. Public health programs and insurance plans are expected to reimburse patients for any costs associated with COVID-19 vaccination, but not much information has been made available yet.

Who Can Get the Johnson & Johnson Vaccine?

Early vaccine efforts for most COVID-19 vaccine candidates are focusing on adult populations, with vaccine options for children and teens expected later in 2021.

The Johnson & Johnson vaccine is no exception.The one- and two-dose vaccines are being tested in adults aged 18 and up with significant representation of individuals over age 60. There are no updates yet on other specific groups for the vaccine.

Side Effects and Adverse Events

In every clinical trial, participants are asked to record any reactions they have after receiving a medication or vaccine. Adverse reactions are considered to be medication reactions directly caused by a vaccine, whereas a side effect is a physical reaction to a medication.

Initial safety information released for the vaccine shows that the most common reactions after the vaccine was administered included:

  • Injection site pain
  • Fatigue
  • Headache
  • Muscle aches

Additional information, including details on the prevalence and duration of side effects, is likely to be included when the final trial report is published.

Funding and Development

Johnson & Johnson is co-funding the development of the vaccine as part of Operation Warp Speed, a public-private partnership initiated by the U.S. government to facilitate and accelerate the development of a COVID-19 vaccine, manufacturing, and distribution of COVID-19 vaccines, with funding from the Biomedical Advanced Research and Development Authority (BARDA)—a U.S. government program aimed at furthering the manufacture and distribution of vaccines to fight COVID-19. Johnson & Johnson said $1 billion has been invested in the vaccine project by both the company and BARDA.

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