WENATCHEE — Wenatchee Valley residents are playing a role in the global development of a potential vaccine for the coronavirus.

Confluence Health is one of more than 100 organizations participating in a Phase 3 trial for a vaccine jointly developed by pharmaceutical companies Pfizer and BioNTech.

This is one of four COVID-19 research projects that Confluence Health has participated in since the pandemic began, said Dr. Steven Kaster, medical director of clinical research. Among the others is the use of a newly approved medication to treat hospitalized patients, which was the organization’s first-ever in-patient study.

The largest so far is the vaccine trial. Confluence’s goal is to enroll at least 150 people — or even up to 200. It started enrolling local participants on Aug. 14 and had 74 people committed as of Wednesday.

In total, the worldwide study will include up to 30,000 participants in the U.S. and countries including Argentina, Brazil and Germany, according to a July news release from Pfizer.

The study is placebo-controlled, meaning half of the participants will receive the trial vaccine and half will be administered a placebo. It’s also randomized and double-blind, so neither the participants or direct researchers know who receives which injection.

But this isn’t a “live” vaccine that would cause participants to become sick with COVID-19, Kaster said.

Instead this vaccine candidate delivers a genetically modified version of messenger RNA, or mRNA, into cells. The body then develops antibodies and immune cells called T cells that would fight off the actual virus, according to The New York Times.

“So the mRNA what it does is it translates into the development of a protein that very much resembles the spike protein of the virus,” Kaster said. “That in turn will elicit the immune response and the antibodies are directed to the spike proteins.”

A Phase 3 study is used to test whether the vaccine is successful in preventing a significant number of participants from being infected by the actual virus. It also helps researchers identify potential side effects.

To qualify, people can’t have been diagnosed with COVID-19 before. They also must be between the ages of 18 and 85, Kaster said.

“There have not been as many people on the younger end of the spectrum that have been as interested compared to the middle or upper,” he said. “And we’d like to enroll with an ethnic diversity that hopefully mirrors the population, so that would be desirable also.”

Anyone with a compromised immune system or who takes medication that suppresses immune response would be disqualified.

“They have to be in relatively good health. Chronic problems are totally acceptable, for instance diabetes or asthma or cardiac disease, as long as those chronic conditions are well controlled and they’re stable,” he said.

Those who meet the criteria are brought in for an initial visit to have a baseline blood sample drawn, Kaster said. Then the first of two doses of the trial vaccine or placebo will be administered, followed by the second dose three weeks later.

“Then, there are several follow-up visits after that, at one month, six months, 12 months, 24 months after the second vaccine,” he said. “Those are mainly to get updates on their overall health and also to draw antibody levels as well to look for their vaccine response.”

While the study will carry on for two years, Pfizer hopes to seek regulatory review as early as October, The New York Times reported. The United States in July entered into a nearly $2 billion contract with Pfizer to produce 100 million doses of the vaccine by December if it’s proven safe and effective.

The U.S. has invested in several candidates, part of an effort to significantly speed up the development timeline for COVID-19 vaccines.

There are currently 23 vaccines in Phase 1 trials, 14 in Phase 2, eight in Phase 3 and two approved for limited use — both of which are outside of the U.S., according to The New York Times.

But it’s unknown when a vaccine will be approved and available for general public use, Kaster said.

“Because things are moving so quickly I would really have a hard time predicting when there will be enough data, both safety-wise and effectiveness-wise, to project when a vaccine will become available,” he said.

But the data from the earlier phases of the Pfizer and BioNTech vaccine looks promising, Kaster said.

“From an effectiveness standpoint from the earlier phase study, there was a good immune response — both levels of antibodies that were directed against the COVID-19 virus and a white cell response as well,” he said. “That data is what prompted the FDA to authorize the phase two and phase three study, the one which we’re participating in.”

Reilly Kneedler: 661-5213

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