A big part of Washington, D.C.’s plan to get its HIV rate down is to get more uninfected people on PrEP, a two-medicine combination pill that’s sold under the brand name Truvada.

When taken daily by people who are at high risk for contracting HIV via sex or shared needles with someone who is infected, this pre-exposure prophylaxis, or PrEP, can cut the risk of HIV infection by 92 percent, studies show.

PrEP has been around for years now, but only a small portion of those at high risk for HIV infection use it, partly because many still don’t know it exists. The medicine is also quite expensive, priced at $1,600 for a month’s supply. It is usually covered by insurance, including Medicaid.

To cut the rate of new infections in half by 2020, D.C. health officials estimate the city will need to more than quadruple the number of residents who are on PrEP. The department of health and community groups are pulling out all the stops to raise awareness.

“Thinking about sex? Then think about PrEP,” one public health commercial says, over video clips of a woman sensually licking an ice cream cone, or a man stroking a golf club. You get the gist.

There are also social media pushes, and an ad campaign called “PrEP for Her” targeting African-American women, who, along with gay and bisexual African-American men, are at high risk of infection in the district.

At a recent conference in the city on LGBTQ issues, Sarah Fleming stopped by the PrEP information table put together by Luis Felipe Cebas of Whitman-Walker Health, a community health center that focuses on providing care to LGBTQ patients.

Fleming told Cebas she’s surprised she had never heard of PrEP. She even got tested for HIV recently.

“They told me nothing about this!” she said. “I was negative — but, I feel like, it’s a preventative, so you should tell people about it.”

Gregorio Millett, vice president and director of public policy at the Foundation for AIDS Research, said some health care providers don’t mention PrEP because of their mistaken belief that it would increase risky sexual behavior; research hasn’t shown that to be the case.

Millett added that there are other reasons why people — especially people of color — haven’t requested PrEP as much as he and other public health officials would like. Some African-Americans distrust the medical community because of historical mistreatment, he said. And there’s still a stigma attached to HIV, especially in some minority communities.

“In order to be prescribed PrEP, you need to be ‘out’ to your provider,” Millett said. “And we see that for African-American men, as well as for Latino gay men, they’re less likely to tell their providers that they are gay or bisexual.”

Several cities across the U.S. — including Seattle, Boston and San Francisco, as well as Washington — are making concerted efforts to overcome these challenges and promote PrEP as a tool for reducing HIV transmission, Millett said.

There are signs of progress in Washington. Whitman-Walker Health has seen a recent uptick in new PrEP patients, including 28-year-old Ricardo Cooper, who lives in the district.

Cooper is gay and HIV-negative. He’s been taking PrEP for a few months, and said he hasn’t experienced many side effects, which can commonly include headaches, nausea and cramping. According to the U.S. Centers for Disease Control and Prevention, these side effects tend to go away over time.

Cooper said taking the drug gives him peace of mind.

“It just makes me feel so much better about engaging in sexual activity,” he said, knowing that he won’t get or transmit HIV to a partner.

He also has found he now talks more openly about HIV, which still carries a lot of stigma among his friends. He said he even walks up to people at bars and sells them on PrEP.

“The professionals can’t really force PrEP on people, but I can,” he chuckled. “And I’ve done that to my friends. It’s like, ‘You don’t have an option.’”

Cooper said, turning serious, that he’s usually a private person but that to him this is important — he wants to do everything he can to spread the word.

“If I need to be the face of PrEP for this African-American community or the communities that are underrepresented — to let them know that, ‘It’s OK, it’s cool, I mean, you should at least try it,’ then I’m perfectly fine with stepping out of myself and doing that,” he said.

Health providers say this kind of community evangelism — along with the bus ads and sexy commercials — will be key to reaching the ultimate goal of ending the HIV epidemic in Washington, D.C.

This story is part of NPR’s reporting partnership with Kaiser Health News.