A line of people worked its way recently through the parking lot at Brookside Community Health Center in Jamaica Plain. The big draw there was free coronavirus testing, but before they left, Carlos Hernandez, a patient navigator at the center, had one last important question to ask them.

"So would you be interested in learning a little bit more about the coronavirus vaccine research study that we're offering to patients?" he asked, handing out a flyer to anyone who said yes.

For the most part, people seemed open to learning more about the trial. But getting those people to actually volunteer to take an experimental vaccine is a bigger lift.

In late July, Cambridge-based Moderna Inc., received approval to begin a Phase 3 clinical trial to study the safety and efficacy of a coronavirus vaccine it has been developing along with the National Institutes for Health. But researchers are running into a challenge that they’ve seen before in other clinical trials — a skepticism from the Black community that’s rooted in a history of racial injustice and present-day healthcare inequities.

Moderna has not responded to multiple requests for interviews about the vaccine trial. But last month, The Washington Post reported that Moderna had enrolled more than 15,000 people in the study, and about 19 percent of those participants are Black, Hispanic or Native American.

Doctors say having more Black participants in the trial will help demonstrate the vaccine works in that population.

As she waited in line to get a COVID test, Samira Lopez of Hyde Park expressed concern that the vaccine was speeding through the approval process too quickly and said she's unlikely to sign up for the trial.

“This came out only a few months after this all started,” she said. “It's probably not safe."

While that’s a concern shared by many, Dr. Bisola Ojikutu, an infectious disease expert at Brigham and Women's, said the skepticism about medical trials in the Black community runs deeper.

"There have been these incredibly egregious events that many people talk about and reference," said Ojikutu, who studies racial and ethnic disparities in research.

She cites Henrietta Lacks, a Black cancer patient whose cervical tissue was taken without her permission in the 1950s and turned into a cell line that’s widely used in research labs today, and the Tuskegee syphilis study, in which Black men were exploited and not treated for the disease for decades, as just two examples.

On top of that history, Ojikutu said, are all the issues of racial inequity in the health care system today. The CDC reportslongstanding social inequities are leading to worse outcomes and greater risk for people of color.

An analysis of racial disparities in COVID deaths by the APM Research Lab shows one in 1,125 Black Americans have died as a result of the virus, compared to one in 2,450 white Americans.

And a study published in the Proceedings of the National Academy of Sciences looked at mortality rates back to 1900 and found that life expectancy has consistently been far better for white Americans than for Black people.

"Then when it comes down to somebody asking you to participate in a trial, the first thing that one may ask oneself, and I think is normal, is, 'Well, but nobody's doing anything about these other things. So then why are we now being asked to do something, you know, that may be harmful?'"

In the early stages of research into the Moderna vaccine, researchers had trouble finding diverse candidates to take part in the study, said Dr. Stephen Walsh, an infectious disease doctor at Brigham and Women's who's working on the Moderna study.

"If you were to look at the demographics of the phase one Moderna study, the average age of the participant was 30 and it was predominantly white individuals who were in the study,” he said. “That's sadly very, very typical of our phase one studies."

Dr. Paulette Chandler, an internist at Brigham & Women’s said the Brookside Community Health Center, said there is a discussion going on within the Black community about whether to participate in the vaccine trials.

“The discussion is happening on Twitter, TikTok, Black talk radio,” Chandler said. “I mean, this discussion is very live and active. And people are actively resisting this vaccine. Now, there are others who say, ‘Yes, I want to be part of this solution.’ That’s a rarity, though.”

As doctors recruit Black people for the trial, they have to be aware of both the historical and modern reasons some patients may hesitate, Ojikutu said.

"We are acknowledging that that's the case, and we are taking every step possible to ensure that you will not face any of that same negative experience, that every safety measure is put into place, and that we will be as transparent as possible with data, with results," Ojikutu said.

In the end, she said, if that trial data does show the vaccine works in people of color, they’re more likely to take the vaccine when it's ready for everyone.