Study explores interaction of HIV drugs, contraception

Kim Scarsi, Pharm.D., associate professor of pharmacy practice, studies the pharmacokinetics of how antiretrovirals — which keep HIV at bay — interact with contraceptives.

She’s found that in many cases the drugs that fight HIV often make contraceptives less potent — and unplanned pregnancies are more likely to result in HIV transmission from mother to child, and increased maternal and child morbidity and mortality.

Now, she’s adapted her research to also include vaginal rings, which are currently used to deliver hormones for hormone replacement therapy as well as contraception. In addition, rings are in clinical trials to deliver the combination of hormones for contraception along with antiretrovirals for HIV prevention in women desiring contraception who are also at risk for HIV infection.

“This is one of the first studies evaluating drug interactions for drugs given via this route of administration, and it has implications beyond just contraception,” she said.

Dr. Scarsi’s study highlights that some drugs taken orally may have significant implications for drugs delivered via a ring.

Following her presentation at CROI 2018, the annual Conference on Retroviruses and Opportunistic Infections, the NIH-funded AIDS Clinical Trials Network said Dr. Scarsi’s latest research study “has major implications for women living with HIV around the world.”

Dr. Scarsi said, at the CROI conference in Boston, her team has discovered that the combination of the antiretroviral efavirenz and the contraceptive ring resulted in an 80 percent decrease of active contraceptive in the blood of women living with HIV.

“If I was a woman receiving an efavirenz-based antiretroviral regimen, I would be uncomfortable with the degree of contraceptive protection I would be getting from the vaginal ring,” she said at a news conference at CROI.

Dr. Scarsi and her team also are busy working to find a drug combination that works, thus positively impacting the lives of women and their families. “This is a population that needs the research,” she said.