The treatment of HIV infection with antiretroviral therapy (ART) has evolved greatly since the 1987 FDA approval of zidovudine, a single agent to which the virus rapidly developed resistance.1,2 Today, health care providers prescribe multidrug regimens containing 2 or more medications with complementary mechanisms of action and/or treatment resistance profiles.2 When used as prescribed, ART can allow people with HIV (PWH) to achieve virologic suppression involving a viral RNA (vRNA) level in the person’s blood that is lower than the limit of detection for diagnostic assays (typically, < 200 vRNA copies/mL of blood).3 The 2014 PARTNER study revealed that virally suppressed PWH are incapable of sexually transmitting the virus to seronegative partners, a finding that would later evolve into the slogan Undetectable = Untransmittable (U = U).4 Additionally, the 2015 START trial (NCT00867048) demonstrated that initiating ART before substantial HIV-related immunosuppression significantly reduced the risk of disease progression to AIDS, transforming HIV from a fatal diagnosis to a manageable chronic condition.3 These treatment successes have prompted policymakers to pursue ambitious public health goals such as Ending the HIV Epidemic (EHE), a US public health initiative to reduce new HIV infections and control viral spread by the year 2030.5
Key goals of EHE include, from 2017 to the end of 2025, reducing new HIV infections and diagnoses by 75%, increasing viral suppression among PWH to 95%, and increasing good or better self-rated health among diagnosed PWH to 95%. The progress demonstrated by data year 2022—the most recently available—must accelerate to meet 2025 targets; in particular, progress must be made towards increasing self-rated health, as progress declined as of data year 2022.5 As identified by the CDC, retention in care and achievement of viral suppression are persistent problems, with only 47% and 57% of PWH, respectively, achieving those metrics in data year 2022.6 Thus, needs among PWH that prevent care retention and successful, sustained achievement of viral suppression remain unmet.
Burdensome treatment effects may explain this problem. Even in the setting of well-controlled viral suppression, patients may be interested in switching, or may need to change, HIV treatment due to adverse events (AEs) or an anticipated drug interaction with a newly prescribed medication.7 The 2024 HIV treatment guidelines published by the US Department of Health and Human Services (HHS) identify AEs, drug-drug interactions (DDI), drug-food interactions (DFI), pill burden, cost, stigma, inconvenience of oral medications, and a desire to simplify a treatment regimen as valid reasons for PWH to switch from one HIV treatment regimen to another.8
This article examines the HIV treatment landscape, focusing on how existing and emerging medications for virally suppressed PWH align with patient and public health goals. Further, it identifies remaining therapeutic gaps as the HIV treatment landscape and patient population continue to evolve.
PWH who take their ART as prescribed may achieve viral suppression, making their HIV a well-managed chronic condition and having their life expectancy approach that of people without HIV.8 After achieving virologic suppression, their comorbid health conditions may still affect overall health status and the treatment burden of PWH substantially. For example, PWH have higher rates of cardiovascular disease, kidney disease, low bone density, and diabetes.9-13 Managing these conditions while maintaining HIV virologic suppression is integral for PWH to achieve and maintain a high quality of life (QOL). Indeed, some patient interviews of older PWH revealed a persistent problem—health care providers focus on HIV management over other health conditions.14 It was not until the World Health Organization (WHO) issued its 2022-2030 update to the global health strategy against HIV, viral hepatitis, and sexually transmitted infections that QOL-related goals were included as a necessary focus to end the HIV epidemic by the year 2030.15,16
Beyond comorbidities, psychosocial factors also contribute to QOL in PWH, and these may be improved with alternative treatment options. As part of the 2015-2016 LATTE-2 (NCT02120352) phase 2b clinical trial for long-acting injectable cabotegravir plus rilpivirine, investigators interviewed 27 trial participants and 12 health care providers from 3 geographically diverse trial sites in the US and 3 clinics in Madrid, Spain, to obtain their views and opinions regarding a long-acting injectable ART regimen.17 The trial started treatment-naïve participants on a 3-drug oral HIV treatment regimen (cabotegravir, abacavir, and lamivudine); participants who achieved viral suppression on this regimen were later randomly assigned to switch to long-acting injectable cabotegravir plus rilpivirine once every 4 or 8 weeks or to continue the daily oral treatment regimen. Comparing the injectable ART to a daily oral regimen, interviewed participants cited convenience, confidentiality, and privacy as reasons for tolerating AEs associated with injections. Some participants discussed travel concerns related to daily oral ART, noting that several countries maintain legal restrictions against PWH entering the territory; for these people, the discretion of long-acting injectable ART was beneficial, because it reduced fear that immigration officials would find HIV medication in their luggage and deny them entry. For other PWH, daily oral ART was considered an unwanted reminder of their HIV diagnosis.17 Since the 2021 approval of long-acting injectable cabotegravir plus rilpiverine,18 PWH who switched to this regimen maintained that it is convenient, allows flexibility over taking a daily oral regimen, and reduces fear/anxiety from missed doses. Challenges patients faced after switching to the long acting–injectable regimen included fear over losing health insurance, long waiting periods for prior authorizations, and wariness of a newly approved medication.19
Ultimately, PWH have multiple personal reasons for seeking an alternative ART treatment regimen, and long acting–injectable options are just 1 solution. Other reasons include to generally improve QOL; to manage drug AEs, DDI, DFI, and toxicity; to improve metabolic profile and treatment adherence; and to reduce treatment costs.8,20-22 Treatment switching has become such a common approach among PWH and their health care providers that some clinical trials are designed for its assessment.23-30 Table 1 summarizes select clinical trials that evaluated treatment switching.23-33
To optimize an ART regimen, health care providers work with their patients to maintain viral suppression without jeopardizing future treatment options. Advances in ART medication and better understanding of HIV drug resistance profiles have made optimization possible. For example, HHS treatment guidelines recommend against monotherapy as a switch strategy due to likely drug resistance. To optimize treatment via shared decision-making, HHS also recommends that PWH and their health care providers consider economic cost.8 However, treatment switching can increase overall health care costs,20 highlighting a need for new, less expensive HIV treatments. Another concern in optimizing treatment is choosing between single-tablet regimens (STRs) and multitablet regimens (MTRs); whereas older MTRs may be familiar to certain patients, MTRs are related to increased risk of treatment failure.34 To achieve and maintain HIV viral suppression according to patients’ personal health situations, health care providers must discuss these topics with their patients.
Currently, at least 11 coformulated ART combinations carry an FDA-approved indication that allows virologically suppressed PWH to switch treatment (Table 2).18,35-44 In alignment with the HHS recommendation against monotherapy, each coformulation contains at least 2 different antiretroviral drugs, most commonly an HIV-1 integrase strand transfer inhibitor (InSTI) plus 1 or 2 reverse transcriptase inhibitors (ie, nucleoside/nucleotide reverse transcriptase inhibitor [NRTI], non-nucleoside reverse transcriptase inhibitor [NNRTI]).18,36,39,41 Also common are 3-drug coformulations that combine NRTIs and NNRTIs.35,37,38,42 Two 4-drug coformulations are available; both contain a cytochrome P450 3A inhibitor (CYP3Ai). The first contains 1 InSTI and 2 different NRTIs alongside the CYP3Ai40; the second maintains the 2 NRTIs and CYP3Ai but swaps the InSTI component for a protease inhibitor.44 Results of recently completed phase 3 trials for a new ART coformulation containing doravirine and islatravir indicated that switching to this combination was noninferior to remaining on the current ART regimen among virologically suppressed PWH.32,33 Doravirine is an NNRTI that is included in another ART coformulation or as a single agent to be included in an MTR38,45; islatravir is a new, investigational nucleoside reverse transcriptase translocation inhibitor (NRTTI).31
Despite many treatment options, optimizing ART while not jeopardizing future treatment options presents a challenge. The Panel on Antiretroviral Guidelines for Adults and Adolescents recommends that clinicians consult an HIV specialist when contemplating regimen switching for a patient with a history of resistance to 2 or more drug classes. Comorbid factors must also be considered. HHS guidelines specifically recommend patients with hepatitis B virus (HBV)/HIV-1 coinfection be treated with a regimen containing a tenofovir derivative. Two-drug regimens are not recommended in patients with HBV/HIV coinfection, because none of the approved 2-drug regimens simultaneously control both viruses.8
Current HIV treatment guidelines offer recommendations to treat stable, virologically suppressed PWH who have recently switched their HIV treatment regimen. Whereas treatment-naïve PWH can generally begin HIV care on any approved ART, treatment switching for virologically suppressed PWH requires consideration of prior treatment failures. Moreover, following any change to HIV treatment, patients must be monitored for 3 months to ensure patient understanding and adherence, monitor any new treatment-emergent AEs, assess regimen tolerance, and guide targeted laboratory testing and medical resource usage (particularly if comorbidities precipitated the treatment switch).8
Health care providers’ concerns about potential treatment failure has caused hesitancy when switching the HIV treatment regimen of virologically suppressed PWH who are stable on their current regimen. Specifically, providers interviewed during the previously mentioned LATTE-2 trial expressed concerns that long-acting ART regimens present unique challenges to clinical management of HIV. Whereas patients in this trial cited the convenience of a long-acting injectable ART regimen as beneficial, interviews with health care providers revealed challenges that could influence treatment switching during shared decision-making conversations. Providers maintain a generally positive stance on long-acting ART, yet they hesitate to recommend these therapies for reasons including patient adherence to infrequent injection visits and the complexities of managing treatment resistance that could emerge from delayed or missed doses. Providers share these concerns for daily oral ART regimens, although the concerns are less pronounced. To paraphrase a provider, patients will not automatically develop treatment resistance from missing 2 or 3 doses of a daily oral regimen provided it does not happen regularly. However, similar nonadherence with a long-acting ART regimen is more concerning, since doses are taken only every 4 or 8 weeks.17 Real-world HIV treatment decisions therefore require careful consideration of patients’ regimen preference and of behavioral and lifestyle factors that could affect adherence.
Payers and insurance formularies also influence HIV treatment decisions in a manner often overlooked by official treatment guidelines. HHS guidelines cite anticipated cost savings as a reason for stable, virologically suppressed PWH to consider switching their ART regimen.8 In practice, an analysis of economic outcomes (all reflecting 2014 US$) revealed higher mean annual health care costs among PWH who switched ART regimens than among PWH who remained on their initial ART regimen ($37,641 vs $31,355, respectively; P < .001). By far, the largest driver of this difference was pharmacy costs for HIV medications ($25,061 vs $22,949). Recognizing that these data could include patients who switched HIV medication due to virologic failure, investigators conducted subanalyses of virologically stable PWH who switched treatment, which yielded similarly higher mean annualized health care costs among treatment switchers versus nonswitchers ($37,120 vs $31,771; P = .006). Likewise, the driving factor in the subanalyses that compared virologically stable switchers versus nonswitchers was higher pharmacy costs related to HIV medications ($30,724 vs $26,313; P = .006).20 Variability in initial payer coverage for new HIV treatment regimens likely constrains patient access and contributes to higher costs for regimen switching.46
To lower new HIV infections by 90% by 2030 and end HIV as a threat to public health, the US EHE initiative set public health targets to reduce new HIV infections and diagnoses, increase viral suppression, and improve the self-rated health status of PWH.5 Baseline metrics came from data year 2017 with interim and final goals establishedfor 2025 and 2030, respectively; federal entities including the White House and the CDC publish regular progress reports. As of 2022, the most recent year with available data, the CDC and the White House reported progress toward most EHE indicators, but that progress needs to accelerate to meet 2025 targets and remain on track to end the HIV epidemic by 2030.5,47 Retention in care and achievement of viral suppression are persistent problems, with only 47% and 57% of PWH, respectively, achieving those metrics in data year 2022.6 Additionally, progress toward bettering self-rated health among PWH declined from baseline year 2017 (71.5%) to 2022 (69.9%).47
Accelerating progress on these metrics and maintaining the ambitious trajectory of the EHE initiative requires identifying and rectifying gaps in HIV care, particularly those that prevent patients from continuing care and achieving viral suppression. In its 2022-2025 National HIV/AIDS Strategy, the White House identified social determinants of health (SDOH) as persistent barriers preventing HIV care access and hindering favorable outcomes for PWH attempting to remain in care.48 Tie-in reporting from the CDC revealed that substance use disorders, mental health problems, unmet socioeconomic needs (ie, food, housing, transportation), limited financial/health insurance resources, and personal schedules that complicate adherence to HIV medication schedules impede care access and retention.49 Although modern medical interventions have extended the life expectancy of PWH, aging and associated comorbidities present other treatment challenges for this population.48,50
Rectifying these barriers to support HIV epidemic control requires a patient-centered treatment approach. Strategies to switch treatment contribute to increased rates of viral suppression and care retention by ensuring that PWH receive the correct regimen at the right time. For example, simplified STRs have shown lower rates of treatment failure than MTRs,34 supporting the HHS recommendation to simplify patients’ treatment by reducing the number of pills or pill frequency.8 Similarly, interviews of PWH who were not retained in care revealed that expenses and transportation were substantial barriers to treatment access; transportation was less important to PWH retained in care.51 Patients facing economic or transportation barriers might, therefore, be better managed and retained in care by following guidelines to switch to either a long-acting regimen that requires less frequent visits to a health care clinic or to a lower-cost regimen.8
Overall, tailoring an HIV treatment regimen to individuals’ clinical and social context can help mitigate the persistent barriers to care access. Switching treatment is not just a clinical decision between patients and their providers; it is a public health tool that supports and advances national goals toward ending the HIV epidemic.
The success of modern ART treatments has led to increased life expectancy among PWH and an aging population living with the disease.48,50 Outside the context of an HIV diagnosis, health problems (eg, hypertension, cognitive decline, cardiovascular disease, renal impairment) and endocrine disorders (eg, insulin resistance, diabetes) are leading causes of death and disability among people 65 years or older.52 In PWH, disease progression can lead to accelerated aging as a result of chronic inflammation, immune system activation, and corresponding cellular damage.53 Accordingly, PWH experience earlier onset of non-AIDS comorbidities than do people without HIV54 and higher rates of non-AIDs comorbidities across all decades of life.55
Although ART has transformed HIV into a manageable chronic condition, its cumulative effects and the treatment of comorbid conditions contribute to the risks associated with polypharmacy in older PWH.53 Aging with HIV presents difficulties for patients and health care providers. For example, patients with well-managed HIV are sometimes frustrated that their providers do not attend to aging-related medical issues; meanwhile, HIV specialists feel less fulfilled in their careers as they focus on aging and family medicine concerns rather than their specialty.14 As it may for SDOH factors affecting access and care retention, switching the HIV treatment regimen of aging PWH—even if the HIV infection is currently well managed—may improve QOL, reduce treatment-related AEs, and sustain viral suppression.
DDI and pill burden are other concerns in disease management for PWH.56 Treating HIV and comorbidities may lead to HIV virologic failure or compromise treatment of the comorbid conditions.56-58 PWH tend to experience onset of select comorbidities at a younger age and have higher rates of these conditions across all decades of life54,55; the prolonged risks of treatment failure could result in aging PWH with lower QOL due to mismanagement of multiple health conditions.
Under these conditions, treatment optimization may require reducing the number of pills prescribed to patients or switching patients from a daily pill regimen to a long-acting injectable to reduce pill fatigue.8 Such a switch would alleviate immediate patient concerns regarding pill burden; however, select medications remain contraindicated for use with some HIV treatment regimens. Interactions that lowerplasma drug concentrations of the HIV regimen could lead to treatment failure,18,38,42 and DDIs could elevate the plasma concentration of the non-HIV treatment and result in serious AEs.40,43
The need to develop HIV treatments related to less-concerning DDIs is ongoing. For example, InSTI-sparing HIV regimens are targeted by ongoing drug development due to the interaction of InSTIs with drugs like dofetilide, which is used to treat aging-associated cardiovascular arrhythmias.36,39 Two recently completed clinical trials showed that switching PWH to the InSTI-sparing doravirine/islatravir combination was noninferior to continued use of an HIV treatment regimen in terms of maintaining viral suppression.31-33 Therefore, doravirine/islatravir and other pipeline HIV treatments currently awaiting regulatory approval could assuage unmet therapeutic needs for older PWH with comorbidities who require HIV therapy with limited drug contraindications.
In 2025, caring for PWH requires navigation of complex individual and public health considerations. This calls for collaborative patient-provider relationships built on trust and open communication to attract infected individuals to therapy and keep patients in HIV treatment. Providers must understand available treatment options and empower PWH in the selection of an optimal regimen. This entails informing PWH about the possibility of switching regimens to optimize their treatment.49 Payers, on the other hand, should consider updating policies and procedures to remove barriers to ongoing care and invest in services that address patients’ medical and nonmedical needs.59 Overall, beginning HIV treatment as soon as possible after diagnosis limits the risk that patients’ disease will progress.3 For instance, rapid ART initiation is associated with improved retention in care and a higher likelihood of achieving an undetectable viral load.60 Rapid and sustained progress toward individual and public management of HIV requires the collaborative engagement of patients, providers, managed care teams, and pharmaceutical research and development.
Care for HIV infection has advanced substantially since the first ART therapies were introduced. Such advancements have brought benefits in terms of viral suppression and improved life expectancy and challenges in terms of managing barriers to care access and achieving and sustaining a high QOL. Likewise, corresponding benefits and challenges are apparent in the sphere of public health. Together, ongoing care and innovation are needed. The path forward involves individualized and shared decision-making, equitable access to treatment, and continued development to alleviate ongoing burdens and meet treatment needs.