Keck Medicine of USC is enrolling volunteers as part of a multicenter clinical trial sponsored by AstraZeneca to determine if an experimental vaccine known as AZD1222 provides protection against the coronavirus. The trial will also test if the study vaccine can reduce the severity of COVID-19 illness in those who become infected.

The Phase 3 clinical trial, which is also funded by the US Biomedical Advanced Research and Development Authority and the National Institute of Allergy and Infectious Diseases, aims to register 30,000 adult volunteers nationally: Keck Medicine plans on enrolling 500 of them.

“Participating in this trial is a historic moment that has great significance not only in the United States but for the entire world,” said the co-investigator of the study Edward Jones-Lopez, MD, MS, an infectious disease specialist at Keck Medicine. “It is an honor to have been selected as one of the trial sites, and we look forward to being part of the solution in the search for a vaccine for COVID-19.”

Prioritizing access for at-risk populations

Keck Medicine is enrolling participants at the greatest risk of contracting the coronavirus, such as those from the Latino and Black communities, those older than 65 and factory workers.

“We want to help those who could benefit the most,” said co-investigator Michael Dube, MD, an infectious disease specialist at Keck Medicine and interim chief of the division of infectious diseases at the Keck School of Medicine of USC.

The clinical trial will operate out of two locations: Keck Hospital of USC and a satellite location in Vernon, California, five miles south of downtown Los Angeles. The researchers, with the support of local health officials, selected Vernon because the city has a high concentration of factories and warehouses, including meat-packing plants. Many meat-packing houses have experienced high infection rates throughout the country during the pandemic.

Study protocol and background

The trial is a randomized, blind, placebo-controlled study. Two-thirds of the subjects will receive the vaccine in the form of two shots one month apart. The other third will receive a placebo injection.

Those receiving the vaccine will be asked to keep a symptom diary and receive periodic follow-up in person and over the phone. Any subject who develops symptoms of COVID-19 will be seen and evaluated as needed. Researchers will measure the rate of symptomatic infection between the group receiving the vaccine and the placebo.

“At the end of the study, if the vaccine proves effective, those who received the placebo will have the option to be vaccinated,” Dube said.

The vaccine was developed by the University of Oxford in partnership with AstraZeneca, a global biopharmaceutical company. An earlier Phase 1/2 trial of more than 1,000 participants found that the vaccine induced a strong immune response to COVID-19, producing antibodies to fight infection, with most participants experiencing only mild side effects, such as fatigue and headaches. Early animal-model research yielded a similar immune response.

The vaccine is made from a weakened version of the common cold virus called an adenovirus that has been genetically modified to contain the coronavirus spike protein, a protein that binds to and infects the cells, explaied Jones-Lopez. Once the protein is introduced into the body, the vaccine theoretically works by priming the immune system to attack the COVID-19 virus if it later infects the body.

Participating in the clinical trial

To volunteer for the study, individuals must be 18 or older who are at high risk of COVID-19 infection and able to comply with study procedures. Participants may have preexisting health conditions, however, must be in stable condition with no hospitalization or worsening of the disease three months before enrollment. People over the age of 65 years are encouraged to participate in this study.

To volunteer for this trial or other federally supported coronavirus vaccine trials either currently underway or planned for the future, please visit the COVID-19 Prevention Network.

— Alison Rainey