A Third Covid-19 Vaccine to Help Save Lives

The FDA authorized the highly effective, single-dose vaccine from Janssen/Johnson & Johnson for emergency use.

Hope is on the horizon. The U.S. Food and Drug Administration (FDA) approved the Janssen Covid-19 Vaccine under emergency use authorization (EUA) on February 27. With 28.4 million confirmed U.S. cases and 508,300 fatalities, we need all the help we can get. We now have three approved vaccines for the prevention of SARS-CoV-2, the virus causing the Covid-19 pandemic.

Janssen Pharmaceutical Companies is the vaccine arm of Johnson & Johnson. The Janssen vaccine is now approved for use in people 18 years and older. It only requires a single dose to be effective and is not burdened by the cold storage requirements, which slowed the distribution of the two previously approved vaccines from Moderna and Pfizer. This vaccine can be mass-produced and widely distributed to help get more shots in more arms as fast as possible.

Like the Moderna and Pfizer vaccines, the Jansen vaccine does not contain a live virus. One cannot catch Covid-19 from these vaccines.

In the past few months, we have heard a lot about how the Pfizer and Moderna Covid-19 vaccines use messenger RNA (mRNA) to invoke immunity. A single strand of mRNA delivers instructions to human cells to produce an antibody against the SARS-CoV-2 spike protein.

The Janssen vaccine uses much older technology by altering a common adenovirus to be used as a delivery system. Adenoviruses are the group of viruses causing the common cold. These viruses can be genetically altered to maintain their efficient ability to get into our bodies but remove their ability to make us sick. This combination makes them excellent vectors to create vaccines.

The Janssen Pharmaceutical Companies proprietary vaccine technology platform, called AdVac, successfully created the Ebola vaccine currently used in the Congo and Rwanda. AdVac is being used to develop vaccine candidates against HIV, RSV, and Zika.

The Janssen vaccine uses Adenovirus 26 (AD26) as the vector to deliver DNA material into our cells to provoke an immune response. Scientists modify the adenovirus by removing its nucleus. They replace the nucleus with genetic instructions to recreate the SARS-CoV-2 spike protein. Our bodies then produce the spike protein triggering our immune system to produce protective antibodies without causing us to get sick.

Forty-four thousand people participated in Janssen’s safety and efficacy clinical trials in the United States, South Africa, and Latin America. The data shows the Janssen vaccine is 72% effective and offered 86% protection against severe disease.

One unanswered scientific question is whether or not vaccinated individuals can still transmit Covid-19 to others. We do not yet know the answer, but the Janssen data in the FDA briefing document reveals promising results. Vaccination reduced asymptomatic infections by 74%.

Some may be alarmed by the lower efficacy rate of 72% compared to the 95% efficacy offered by Pfizer and Moderna. It is important to remember these numbers are not direct head-to-head comparisons. Scientists performed the clinical trials for each vaccine in different parts of the world at various pandemic stages.

The key takeaway is all three vaccines are very effective.

Thank you Medium Coronavirus Blog for publishing this article on Medium.

Blog Author: Dr. Jeff Livingston 

Main Blog Photo By: Prostock-Studio Istock by Getty