Johnson & Johnson gets EUA in India: Here's your ultimate guide to the single-dose vaccine

Global healthcare major Johnson & Johnson on Saturday received Emergency Use Authorization (EUA) for its single-dose COVID-19 vaccine in India, Union Health Minister Mansukh Mandaviya tweeted. The company had revealed it has sought EUA in India on Friday.  The vaccine was one of the early candidates to have been cleared by the US Centers for Disease Control, and Prevention (US CDC) and was said to have high efficacy at preventing hospitalisation and death in people. But the vaccine has run into one hurdle after another, notwithstanding the promising trial results. Here's everything you need to know about the Johnson and Johnson vaccine.

How is it different?

Unlike its US counterparts, Moderna and Pfizer vaccines, the Johnson & Johnson vaccine does not use messenger RNA (mRNA) to help the body build its defenses against the virus. Instead, it is an adenovector vaccine like the Oxford-AstraZeneca vaccine. In this case, the gene of the coronavirus’ signature spike protein is added to an adenovirus, a common virus that causes colds or flu-like symptoms, which when introduced into the body, delivers the instructions that teach human cells to make the spike protein. That causes the immune system to react by making antibodies to attack the spike protein, so if the person is exposed to COVID-19, the immune system is ready to fight it. It must also be mentioned that the adenovirus is modified so it can enter cells but cannot replicate or cause illness.

Why did the J&J vaccine have the advantage of time?

The Johnson & Johnson 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 Center, Boston. A history of the vaccine shows that its central formula was in making over a decade before the outbreak of the coronavirus. Dan Barouch, a virologist at the Beth Israel Deaconess Medical Center, and his team had been developing a “vector” for the last decade and a half, as per which a part of a pathogen’s genetic code would be introduced into human cells. Once there, it would trigger the cells to create pieces of the pathogen for the body’s immune system to identify and attack. Barouch’s vector, called Ad26, was a variant of adenovirus, which causes the common cold. They had already used Ad26 to make vaccines for HIV, tuberculosis, and Zika.

How does it fare?

• Johnson & Johnson vaccine is currently the only vaccine, which is effective after only one dose. Authorities can use this vaccine on people who may be hard to reach or who are otherwise unlikely to get a second dose.
• Unlike all Indian vaccines, which have to be stored at 2-8 degrees Celsius, the Johnson & Johnson vaccine can be refrigerated for up to three months at normal temperatures. This would allow the government to send these stocks to rural parts of the country where the cold chain may not be well developed.
• Johnson & Johnson said a study showed the vaccine was 85 percent effective against “severe/critical disease and demonstrated protection against hospitalisation and death”.
• The vaccine was effective across regions studied globally, including in South Africa and Brazil, “where there was a high prevalence of rapidly emerging Beta and Zeta (P.2) variants during the study period”, according to the company.
• The vaccine was 66.3 percent effective in clinical trials (efficacy) at preventing laboratory-confirmed COVID-19 infection in people who received the vaccine and had no evidence of being previously infected.
• A single dose of the vaccine generated neutralising antibodies against a range of Sars-CoV-2 variants of concern, including against Delta (B.1.617.2), Beta (B.1.351), Gamma (P.1).

What is the recommended dosage?

According to the Strategic Advisory Group of Experts of WHO, the single dose (0.5 ml) Janssen Ad26.CoV2.S vaccine should be administered intramuscularly. Further, there should be an interval of 14 days before the administration of this vaccine and any other vaccine against other health conditions.

Why is the J&J vaccine mired in controversies?

The Johnson & Johnson vaccine has been plagued by one controversy after another. For instance, On 13 April, the US government paused the administration of the vaccine to investigate a few cases in which people experienced blood clots after receiving the vaccine. All of the cases emerged within two weeks of vaccination. But on 23 April, US health officials lifted the pause after scientific advisers decided the vaccine’s benefits outweigh the risks.

Again, earlier in the month social media users shared posts, which claimed that the vaccine contains aborted fetal DNA as an ingredient, to which the Roman Catholic Archdiocese of New Orleans released a statement calling it "morally compromised". It was later clarified that while the vaccine used lab-replicated fetal cells during its production process, the vaccine itself does not contain any fetal cells.

Besides, as per recent reports, the vaccine increases the risk of Guillain-Barré syndrome during the 42 days following the vaccination. While the vaccine has not been proven to be a causative effect of the disorder, influenza and shingles vaccines have been linked to an increased risk of contracting the syndrome.

What is the implication for India?

Johnson & Johnson's inclusion in India’s vaccine list will not only give the country one more option, besides the Covaxin, Covishield and Sputnik V, but also boost the availability of the shots. This gains in significance given that the country has recently been criticised for its slow pace of vaccination.