A US study of routine clinical care found that no women taking long-acting cabotegravir (Apretude) for HIV pre-exposure prophylaxis (PrEP) developed an HIV infection, even when some experienced short delays before receiving maintenance injections, according to data from the OPERA longitudinal cohort between 2021 and 2024.
The findings tracked 315 women over a median follow-up period of 13 months. The lack of incident HIV cases despite treatment interruptions suggests a level of resilience in the long-acting formulation that could address common barriers to medication adherence.
Cabotegravir and the Shift to Long-Acting PrEP
Pre-exposure prophylaxis, or PrEP, consists of antiretroviral drugs used by HIV-negative individuals to prevent the acquisition of the virus. While traditional oral PrEP—typically tenofovir-based—is highly effective when taken daily, it faces significant hurdles.
To counter these challenges, medical innovation has shifted toward longer-acting formulations. These include the cabotegravir injection and the dapivirine vaginal ring, which is a silicone matrix ring that releases antiretroviral drug over a month to reduce HIV risk. Both options offer users greater discretion and a reduced need for frequent dosing.
Implementation studies emphasize that the delivery of injectable cabotegravir and vaginal rings can be optimized by drawing on lessons from oral PrEP, including provider training, demand creation, client decision-support tools, and community co-development.
Barriers to PrEP Persistence in Women
The transition to injectables is particularly relevant given the specific social and biological factors, as well as gender inequities and social norms, that heighten HIV susceptibility for women.
Efforts to integrate these services into routine health care have seen mixed results. For example, integrating PrEP into routine family planning clinics in Kenya proved feasible and achieved universal risk screening; however, continuation rates declined sharply by three months. Programme data from these efforts underscore the influence of age, contraceptive method, and partner HIV status on initiation and follow-up.
To expand PrEP coverage and persistence, research suggests combining biomedical innovation with adaptive adherence support and community-centred, youth-friendly delivery. Differentiated service delivery models—such as mobile clinics, pharmacy distribution, and telehealth—have been used to address access barriers.
HIV Progression and the Role of ART
The importance of effective prevention like cabotegravir is underscored by the nature of the virus. As HIV.gov explains, HIV (human immunodeficiency virus) attacks cells that help the body fight infection, making a person more vulnerable to other diseases. It is spread through contact with certain bodily fluids, most commonly through sharing injection drug equipment or unprotected sex (sex without a condom or HIV medicine to prevent or treat HIV).
If left untreated, HIV can lead to AIDS (acquired immunodeficiency syndrome), the late stage of infection that occurs when the body’s immune system is badly damaged. A person with HIV is considered to have progressed to AIDS when they develop one or more opportunistic infections regardless of their CD4 count, or when their CD4 cells fall below 200 cells per cubic millimeter of blood. In a healthy immune system, CD4 counts are between 500 and 1,600 cells/mm3.
Without HIV medicine, people with AIDS typically survive about 3 years; if a dangerous opportunistic illness develops, life expectancy without treatment falls to about 1 year. However, in the U.S., most people living with HIV do not develop AIDS because of antiretroviral therapy (ART). When taken as prescribed, ART can lead to viral suppression, where the viral load is reduced to a very low level. If the viral load is so low that a standard lab cannot detect it, it is called an undetectable viral load. People who maintain an undetectable viral load will not transmit HIV to their HIV-negative partners through sex.
Clinical Outcomes and Risk Assessment
The effectiveness of PrEP is tied to the precision of risk identification and the consistency of use, defined as the consistent and correct use of PrEP according to the prescribed regimen. While the OPERA cohort showed success despite short delays, other clinical observations emphasize the interaction between the level of adherence and the effectiveness of PrEP.
Post-exposure prophylaxis (PEP) is another tool, consisting of HIV medicine taken within 72 hours after a possible exposure to prevent the virus from taking hold. For those at risk, the only way to know for sure if they have HIV is to get tested through health care providers, hospitals, community health centers, substance abuse programs, or via HIV self-testing.
The success of the 315 women in the OPERA study indicates that long-acting injectables may provide a critical safety net for those who struggle with the rigid schedules of daily medication, potentially expanding the reach of prevention services to those most vulnerable to treatment interruptions.
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