Worldwide, nearly half of new HIV infections among adults in 2019 occurred in women. However, a long list of obstacles has prevented many women from taking medications that can prevent HIV infection.
They could help recent and promising news about a different HIV prevention regime. A large clinical trial found that a long-term injection of an HIV drug given once every eight weeks was safer and more effective in preventing infection in women than a daily pill of two HIV drugs.
“This is incredibly exciting,” says Bisola Ojikutu, a doctor of infectious diseases at Brigham and Women’s Hospital and Massachusetts General Hospital in Boston, who did not participate in the trial. If the injection is approved by the U.S. Food and Drug Administration, she said, women will have the option of a discreetly administered HIV prevention drug that does not require daily care.
Although women make up a minority of newly diagnosed HIV patients in the United States, their HIV-related mortality rate, 5.4 per 1,000 people diagnosed, was higher than that of men (4.5 per 1,000) or women. transgender (4.3 per 1,000) in 2017, researchers reported on Nov. 20 in the Weekly Morbidity and Mortality Report.
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Women face many barriers when it comes to protecting themselves from HIV infection. A woman's HIV risk is linked not only to measures in her control, but also to the amount of HIV transmission in her community, whether she has reliable health care or is living in poverty or experiencing intimate partner violence (SN: 11/15/19). But studies have found that women at high risk due to social factors tend to underestimate their individual risk.
Most cisgender women acquire HIV during heterosexual contact; women are twice as likely as men to contract HIV during vaginal sex with an infected partner. Condoms are a useful HIV prevention tool but their use is not entirely under a woman’s control. Medications to prevent infection in an HIV-negative person at risk, called pre-exposure prophylaxis or PrEP, were approved in the United States in 2012. Taken consistently, the daily pill form of PrEP can reduce the risk of contracting HIV during vaginal sex. up to 90 percent and up to 99 during anal sex.
Even if a woman knows she has a high risk of contracting HIV, she may not know about PrEP. Awareness and use of the PrEP pill, called Truvada, in the United States remains low among women; they were only 6 percent of the more than 100,000 U.S. users in 2017, according to a 2018 Annals of Epidemiology study in a national revenue database. And for women taking the PrEP pill, maintaining the daily routine can be a challenge due to the side effects of the medication or the stigma.
“Most of my patients living with HIV haven’t told anyone,” Ojikutu says. That stigma can extend to the PrEP pill. Taking a daily medication to prevent HIV may appear to others as if the person is receiving HIV treatment.
Fears that family and friends would assume they were HIV-positive or that a couple would accuse them of infidelity were among those who believed women in the Washington DC area about PrEP, researchers reported in the Journal of AIDS Clinical Research in 2017. Adolescent girls and young women in Zimbabwe and South Africa were also concerned about being thought HIV-positive or called promiscuous if they were taking PrEP, according to a March 2020 study published in the Journal of the International AIDS Society.
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Having a more discreet way of taking PrEP, such as an infrequent injection, could be appealing to many women. “It’s private,” says infectious disease doctor Mina Hosseinipour of the University of North Carolina School of Medicine in Chapel Hill. "This only allows women a lot of autonomy."
At the Phase III trial, which began in 2017, Hosseinipour and colleagues enrolled more than 3,000 sexually active cisgender women with HIV aged 18 to 45 in East and Southern Africa. In this region, women accounted for 61 percent of new HIV infections among 15-year-olds in 2019, and young women accounted for 73 percent of new infections among 15- to 24-year-olds, according to UNAIDS. These women are not always able to “defend themselves and their prevention needs,” due to their social position and vulnerability, says Hosseinipour, who has lived and worked in Malawi, Southeast Africa, since 2001.
Trial participants were randomly assigned to receive an injection of cabotegravir from the HIV drug once every eight weeks and a daily placebo pill or a placebo injection at the same time and a daily PrEP pill.
Of the 38 women who became infected with HIV, four received the cabotegravir injection and 34 took PrEP pills, the National Institutes of Health announced on November 9th. This is an HIV incidence rate of 0.21 percent in the injection group and 1.79 percent in the pill group. These provisional results were so good (the injection reduced infections by 89 percent compared to the pill) that the safety board that oversaw the trial recommended to participants what medications they are receiving, so that women have the option to switch to the injection. . Researchers will continue to follow trial participants to assess long-term safety.
Promising results follow those reported for a trial with cisgender men and transgender women who have had sex with men; injections reduced infections by 66 percent compared to daily PrEP pills in that trial, the researchers reported in July 2020 at the International AIDS Conference.
Having a new PrEP option does not change the fact that greater reach must be given to HIV prevention targeted at women, through public health campaigns and community engagement, Ojikutu says. And as for doctors, asking about HIV risk “has to be part of our routine commitment to patients,” she says. "It must be an ongoing interaction" to understand "the determinants of risk in every woman's life."