The first Phase 1 human trial of a potential vaccine to protect against COVID-19 has injected its first patient in Seattle, according to the National Institutes of Health (NIH). Currently, no approved vaccines exist to prevent infection with SARS-CoV-2.

The vaccine, known as mRNA-1273, was developed by NIH National Institute of Allergy and Infectious Diseases (NIAID) scientists and biotechnology company Moderna Inc.


The investigational vaccine was developed using a genetic platform called mRNA (messenger RNA). The investigational vaccine directs the body’s cells to express a virus protein that it is hoped will elicit a robust immune response. The mRNA-1273 vaccine has shown promise in animal models, and this is the first trial to examine it in humans.

The open-label trial will enroll 45 healthy adult volunteers ages 18 to 55 years over approximately 6 weeks. The first participant received the investigational vaccine Mar 16, according to the NIH.

The study is evaluating different doses of the experimental vaccine for safety and its ability to induce an immune response in participants, the NIH said in a statement. This is the first of multiple steps in the clinical trial process for evaluating the potential benefit of the vaccine, it reported.

“Finding a safe and effective vaccine to prevent infection with SARS-CoV-2 is an urgent public health priority,” NIAID director Anthony S. Fauci, MD said in a press release. “This Phase 1 study, launched in record speed, is an important first step toward achieving that goal.”

The Phase 1 trial is led by Lisa A. Jackson, M.D., senior investigator at KPWHRI. Study participants will receive two doses of the vaccine via intramuscular injection in the upper arm approximately 28 days apart. Each participant will be assigned to receive a 25 microgram (mcg), 100 mcg or 250 mcg dose at both vaccinations, with 15 people in each dose cohort. The first four participants will receive one injection with the low dose, and the next four participants will receive the 100 mcg dose. Investigators will review safety data before vaccinating the remaining participants in the 25 and 100 mcg dose groups and before participants receive their second vaccinations. Another safety review will be done before participants are enrolled in the 250 mcg cohort.

Participants will be asked to return to the clinic for follow-up visits between vaccinations and for additional visits across the span of a year after the second shot. Clinicians will monitor participants for common vaccination symptoms, such as soreness at the injection site or fever as well as any other medical issues. A protocol team will meet regularly to review safety data, and a safety monitoring committee will also periodically review trial data and advise NIAID. Participants also will be asked to provide blood samples at specified time points, which investigators will test in the laboratory to detect and measure the immune response to the experimental vaccine.

“This work is critical to national efforts to respond to the threat of this emerging virus,” Dr. Jackson said. “We are prepared to conduct this important trial because of our experience as an NIH clinical trials center since 2007.”

Adults in the Seattle area who are interested in joining this study should visit https://corona.kpwashingtonresearch.org.

For more information about the study, visit ClinicalTrials.gov and search identifier NCT04283461.

The Coalition for Epidemic Preparedness Innovations (CEPI) supported the manufacturing of the vaccine candidate for the Phase 1 clinical trial.