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SLU’s Center for Vaccine Development Begins Recruiting Participants for Phase 3 COVID-19 Investigational Vaccine Clinical Trial

12/11/2020Media Inquiries

Carrie Bebermeyer
Public Relations Director

Reserved for members of the media.


NOTE: Participant recruitment for the ENSEMBLE trial has concluded. Information about upcoming studies will be shared at as it becomes available.

Dec. 11, 2020 – Saint Louis University’s Center for Vaccine Development will be a testing site for the Janssen Pharmaceutical Companies of Johnson & Johnson’s Phase 3 clinical research study, ENSEMBLE trial, to evaluate the safety and efficacy of Janssen’s investigational COVID-19 vaccine candidate, JNJ-78436735, also known as Ad26.COV2.S.

The Phase 3 randomized, double-blind, placebo-controlled clinical trial is designed to evaluate the safety and efficacy of a single vaccine dose of the Janssen investigational COVID-19 vaccine candidate versus placebo in adults 18 years old and older, including significant representation from those that are over 60.

The trial will include those both with and without comorbidities associated with an increased risk for progression to severe COVID-19. SLU will enroll up to 250 adults aged 18 and up from the St. Louis metropolitan area.

“Scientists around the country have been working tirelessly to develop a vaccine that is safe and protects against COVID-19,” said Sharon Frey, M.D., clinical director of SLU’s Center for Vaccine Development and principal investigator of the Janssen trial at SLU.

“St. Louisans will play a key role in the historic effort to develop a COVID-19 vaccine,” Frey said. “It’s important that we study the vaccine for all people, including healthy people, those with underlying conditions, people over 60 as well as those who are younger and people of all races and ethnicities.”

To learn more about participating in the COVID-19 vaccine trial at Saint Louis University, please visit and complete the questionnaire or call 314-977-6333 or 1-866-410-6333.

To support the recruitment process, Janssen has developed the ENSEMBLE Study website where people interested in volunteering for the study can register. All registration information will be collected, handled and stored according to the local laws and regulations. Following registration, the research centers will evaluate volunteers’ information and then potentially request physical tests before the volunteer is included in the study.

The ENSEMBLE website also brings details on the trial, such as medical monitoring and a questions and answers section. Janssen has joined other pharmaceutical companies in making a pledge to the world that it will continue to adhere to its high scientific, ethical and regulatory standards and will rely on robust clinical evidence to guide the development of its investigational COVID-19 vaccine candidate.

Janssen is committed to transparency and sharing information related to the Phase 3 ENSEMBLE study – including the study protocol. Janssen’s investigational COVID-19 vaccine leverages Janssen’s AdVac® technology. The same technology was used to develop Janssen’s European Commission approved Ebola vaccine regimen and is the basis for its HIV, RSV and Zika vaccine candidates. To date, more than 100,000 individuals have been vaccinated with a Janssen AdVac® -based vaccine.

ENSEMBLE is being initiated in collaboration with the Assistant Secretary for Preparedness and Response (ASPR), Biomedical Advanced Research and Development Authority (BARDA) and the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH).

Saint Louis University’s Center for Vaccine Development is part of the NIAID-supported COVID-19 Prevention Network (CoVPN). The CoVPN is composed of existing NIAID-supported clinical research networks with infectious disease expertise and is designed for rapid and thorough evaluation of vaccine candidates and monoclonal antibodies for the prevention of COVID-19. More information about the trial is available at:

About the Saint Louis University Center for Vaccine Development

Saint Louis University has been on the front lines in the fight against pandemics and global health crises for more than three decades and first received federal funding for vaccine research in 1989. Led by Daniel Hoft, M.D., Ph.D., SLU’s Center for Vaccine Development is one of only 10 institutions selected by the National Institutes of Health as a Vaccine and Treatment Evaluation Unit (VTEU).

As a VTEU, the Center helps develop and evaluate vaccines that will protect people from infectious diseases and emerging threats. It conducts Phase 1 through 4 vaccine and treatment trials, including clinical studies in collaboration with industry partners. Hoft serves as the VTEU’s principal investigator.

About the Saint Louis University School of Medicine

Established in 1836, Saint Louis University School of Medicine has the distinction of awarding the first medical degree west of the Mississippi River. The school educates physicians and biomedical scientists, conducts medical research, and provides health care on a local, national and international level. Research at the school seeks new cures and treatments in five key areas: infectious disease, liver disease, cancer, heart/lung disease, and aging and brain disorders.