J&J’s One-Shot COVID-19 Vaccine Advances to Phase 3 Testing

Kerry Dooley Young

September 23, 2020

Editor's note: Find the latest COVID-19 news and guidance in Medscape's Coronavirus Resource Center.

Johnson & Johnson (J&J) on Wednesday said it advanced into phase 3 testing of its COVID-19 vaccine candidate, which uses the same technology as an Ebola vaccine already approved by European regulators.

The National Institute of Allergy and Infectious Diseases (NIAID), which is aiding Johnson & Johnson with development, described this in a news release as the fourth phase 3 clinical trial of evaluating an investigational vaccine for coronavirus disease.

This NIAID tally tracks products likely to be presented soon for US Food and Drug Administration (FDA) approval. (The World Health Organization's COVID vaccine tracker lists nine candidates as having reached this stage, including products developed in Russia and China.)

As many as 60,000 volunteers will be enrolled in the trial, with about 215 clinical research sites expected to participate, NIAID said. The vaccine will be tested in the United States and abroad.

The start of this test, known as the ENSEMBLE trial, follows positive results from a Phase 1/2a clinical study, which involved a single vaccination. The results of this study have been submitted to medRxiv and are set to be published online imminently.

New Brunswick, New Jersey-based J&J said it intends to offer the vaccine on "a not-for-profit basis for emergency pandemic use." If testing proceeds well, J&J might seek an emergency use clearance for the vaccine, which could possibly allow the first batches to be made available in early 2021.

J&J's vaccine is unusual in that it will be tested based on a single dose, while other advanced candidates have been tested in two-dose regimens.

J&J on Wednesday also released the study protocol for its phase 3 test. The developers of the other late-stage COVID vaccine candidates also have done this, as reported by Medscape Medical News. Because of the great interest in the COVID vaccine, the American Medical Association had last month asked the FDA to keep physicians informed of their COVID-19 vaccine review process.

Trials and Tribulations

One of these experimental COVID vaccines already has had a setback in phase 3 testing, which is a fairly routine occurrence in drug development. But with a pandemic still causing deaths and disrupting lives around the world, there has been intense interest in each step of the effort to develop a COVID vaccine.

AstraZeneca PLC earlier this month announced a temporary cessation of all their coronavirus vaccine trials to investigate an "unexplained illness" that arose in a participant, as reported by Medscape Medical News.

On September 12, AstraZeneca announced that clinical trials for the AZD1222, which it developed with Oxford University, had resumed in the United Kingdom. On Wednesday, CNBC said Health and Human Services Secretary Alex Azar told the news station that AstraZeneca's late-stage coronavirus vaccine trial in the US remains on hold until safety concerns are resolved, a critical issue with all the fast-track COVID vaccines now being tested.

"Look at the AstraZeneca program, phase 3 clinical trial, a lot of hope. [A] single serious adverse event report in the United Kingdom, global shutdown, and [a] hold of the clinical trials," Azar told CNBC.

The New York Times has reported on concerns stemming from serious neurologic illnesses in two participants, both women, who received AstraZeneca's experimental vaccine in Britain.

The Senate Health, Education, Labor and Pensions Committee on Wednesday separately held a hearing with the leaders of the FDA and the Centers of Disease Control and Prevention, allowing an airing of lawmakers' concerns about a potential rush to approve a COVID vaccine.

Details of J&J Trial

The J&J trial is designed primarily to determine if the investigational vaccine can prevent moderate to severe COVID-19 after a single dose. It also is designed to examine whether the vaccine can prevent COVID-19 requiring medical intervention and if the vaccine can prevent milder cases of COVID-19 and asymptomatic SARS-CoV-2 infection, NIAID said.

Principal investigators for the phase 3 trial of the J & J vaccine are Paul A. Goepfert, MD, director of the Alabama Vaccine Research Clinic at the University of Alabama in Birmingham; Beatriz Grinsztejn, MD, PhD, director of the Laboratory of Clinical Research on HIV/AIDS at the Evandro Chagas National Institute of Infectious Diseases-Oswaldo Cruz Foundation in Rio de Janeiro, Brazil; and Glenda E. Gray, MBBCh, president and chief executive officer of the South African Medical Research Council and co-principal investigator of the HIV Vaccine Trials Network (HVTN).

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