The cost-effectiveness of preexposure prophylaxis for HIV prevention in the United States in men who have sex with men

Costs and Cost-Effectiveness of Biomedical, Non-Surgical HIV Prevention Interventions: A Systematic Literature Review

BACKGROUND

Considerable evidence on the costs and cost-effectiveness of biomedical, non-surgical interventions to prevent human immunodeficiency virus (HIV) transmission has been generated over the last decade. This study aims to synthesize findings and identify remaining knowledge gaps to suggest future research priorities.

METHODS

A systematic literature review was carried out in August 2020 using the MEDLINE, Embase, Global Health and EconLit databases to retrieve economic evaluations and costing studies of oral pre-exposure prophylaxis (PrEP), injectable long-acting PrEP, vaginal microbicide rings and gels, HIV vaccines and broadly neutralizing antibodies. Studies reporting costs from the provider or societal perspective were included in the analysis. Those reporting on behavioural methods of prevention, condoms and surgical approaches (voluntary medical male circumcision) were excluded. The quality of reporting of the included studies was assessed using published checklists.

RESULTS

We identified 3007 citations, of which 87 studies were retained. Most were set in low- and middle-income countries (LMICs; n = 53) and focused on the costs and/or cost-effectiveness of oral PrEP regimens (n = 70). Model-based economic evaluations were the most frequent study design; only two trial-based cost-effectiveness analyses and nine costing studies were found. Less than half of the studies provided practical details on how the intervention would be delivered by the health system, and only three of these, all in LMICs, explicitly focused on service integration and its implication for delivery costs. 'Real-world' programme delivery mechanisms and costs of intervention delivery were rarely considered. PrEP technologies were generally found to be cost-effective only when targeting high-risk subpopulations. Single-dose HIV vaccines are expected to be cost-effective for all groups despite substantial uncertainty around pricing.

CONCLUSIONS

A lack of primary, detailed and updated cost data, including above-service level costs, from a variety of settings makes it difficult to evaluate the cost-effectiveness of specific delivery modes at scale, or to evaluate strategies for services integration. Closing this evidence gap around real-world implementation is vital, not least because the strategies targeting high-risk groups that are recommended by PrEP models may incur substantially higher costs and be of limited practical feasibility in some settings.

Cost utility analysis of HIV pre exposure prophylaxis among men who have sex with men in Israel

Background

Between 2011 and 2015, Men who have sex with men (MSM) accounted for nearly half of new HIV cases among men in Israel. This study carries out a cost-utility analysis of PrEP (HIV Pre Exposure Prophylaxis), an antiretroviral medication that can protect against the acquisition of HIV infection, whose incidence rate in Israel is around 1.74 per 1000 MSM.

Method

Epidemiological, demographic, health service utilisation and economic data were integrated into a spread-sheet model in order to calculate the cost per averted disability-adjusted life year (DALY) of the intervention from a societal perspective, in mid-2018 US$ using a 3% discount rate. Cost utility analyses were performed for both types of PrEP delivery (continuous regimen and on-demand), together with sensitivity analyses on numbers of condom users who take up PrEP (baseline 25%) and subsequently abandon condom use (baseline 75%), PrEP efficacy (baseline 86%), PrEP prices and monitoring costs.

Results

Around 21.3% of MSM are high risk (as defined by having unprotected anal intercourse). Offering PrEP to this group would have a ten year net cost of around 1563 million USD, preventing 493 persons from becoming HIV-positive, averting around 1616 DALYs at a cost per averted DALY of around 967,744 USD. This will render the intervention to be not cost-effective. PrEP drug prices would have to fall dramatically (by 90.7%) for the intervention to become cost-effective (i.e. having a cost per averted DALY less than thrice GNP per capita) in Israel. PrEP remains not cost-effective (at 475,673 USD per averted DALY) even if intervention costs were reduced by using an “on demand” instead of a daily schedule. Even if there were no changes in condom use, the resultant 411,694 USD cost-utility ratio is still not cost-effective.

Conclusions

Despite PrEPs high effectiveness against HIV, PrEP was found not to be cost-effective in the Israeli context because of a combination of relatively low HIV incidence, high PrEP costs, with a likelyhood that some low-risk MSM (ie: who use condoms) may well begin taking PrEP and as a consequence many of these will abandon condom use. Therefore, ways of minimizing these last two phenomena need to be found.

Cost-Effectiveness of a Statewide Pre-Exposure Prophylaxis Program for Gay, Bisexual, and Other Men Who Have Sex with Men

Pre-exposure prophylaxis (PrEP) is an effective tool for preventing HIV infection among men who have sex with men (MSM), but its cost-effectiveness has varied across settings. Using an agent-based model, we projected the cost-effectiveness of a statewide PrEP program for MSM in Rhode Island over the next decade. In the absence of PrEP, the model predicted an average of 830 new HIV infections over ten years. Scaling up the existing PrEP program to cover 15% of MSM with ten or more partners each year could reduce the number of new HIV infections by 33.1% at a cost of $184,234 per quality-adjusted life-year (QALY) gained. Expanded PrEP use among MSM at high risk for HIV infection has the potential to prevent a large number of new HIV infections but the high drug-related costs may limit the cost-effectiveness of this intervention.

Psychosocial Functioning and Decisional Balance to Use Condoms in a Racially/Ethnically Diverse Sample of Young Gay/Bisexual Men Who Have Sex with Men

Young gay/bisexual and other men who have sex with men (YGBMSM; ages 18-24) are experiencing an increase in HIV infection rates, particularly if they are Black or Latino. Psychosocial functioning is consistently implicated in HIV risk behaviors; however, less is known about the role of these factors in YGBMSM's decision-making process to use condoms (i.e., decisional balance to use condoms; DBC). We examined whether YGBMSM's psychological functioning was associated differentially with their DBC across racial/ethnic groups. Using data from a cross-sectional web-survey of single YGBMSM (N = 1380; 9.9% Black; 18.6% Latino; 71.5% White), we performed racial/ethnic-specific multivariable regression models to explore the association between DBC and psychological factors (e.g., depression, anxiety), demographics (e.g., age, education, HIV status, prior STI diagnosis), and perceived difficulty implementing safer sex strategies. Black YGBMSM reported lower DBC if they reported higher depression symptoms (β = -.31, p < .05), were HIV-negative (β = -.20, p < .05), and had greater difficulty implementing safer sex strategies (β = -.32, p < .001). Latino participants reported greater DBC to use condoms if they reported greater anxiety symptoms (β = .21, p < .05). White participants reported greater DBC if they were younger (β = -.09, p < .01), did not report a prior STI (β = .10, p < .001), and had fewer difficulties implementing safer sex strategies (β = -.27, p < .001); DBC had no association to psychological well-being among White participants. Psychological factors may be differentially associated with DBC across racial/ethnic group categories. Health promotion initiatives targeting condom use may benefit from culturally tailored interventions that address psychosocial functioning and its role in YGBMSM's condom use decision-making.

Optimizing Pre-Exposure Antiretroviral Prophylaxis Adherence in Men Who Have Sex with Men: Results of a Pilot Randomized Controlled Trial of "Life-Steps for PrEP"

Antiretroviral pre-exposure prophylaxis (PrEP) has been demonstrated to decrease HIV acquisition in multiple efficacy trials, but medication adherence is critical, and was suboptimal in several studies. Fifty HIV-uninfected at risk men who have sex with men (MSM) were randomized to a cognitive behavioral intervention condition or a time and session-matched comparison counseling intervention. The experimental intervention entailed four nurse-delivered initial and two booster sessions based on Life-Steps, an ART treatment adherence intervention. The comparison condition provided information and supportive counseling. The primary analyses compared adherence (Wisepill and tenofovir plasma levels) at 3 and 6 months. Fifty-eight MSM were screened to enroll 50 participants. Median age was 38.2 years old, 86% were white; 64% had completed college. Wisepill adherence was high in both groups, and not statistically different. Plasma tenofovir levels were significantly higher in the intervention group at 6 months using mean substitution analysis (i.e., computing missing variables) (p = 0.037), however, in the completer analyses (i.e., using only those completing all study visits), there were no statistically significant differences between randomization conditions. Medication adherence was high across a cognitive-behavioral (Life-Steps) and time-matched counseling intervention for PrEP adherence, with some evidence suggesting superiority of Life-Steps in this pilot RCT. Further evaluation in a fully powered efficacy trial is warranted to assess the robustness of this intervention.

Trends in HIV prevalence and risk behavior among men who have sex with men in New York City, 2004-2011

This study examined trends in HIV prevalence and HIV-related risk behaviors from 2004 through 2011 among men who have sex with men (MSM) in New York City. MSM were venue-sampled, interviewed, and offered HIV testing in serial cross-sectional studies. Significant differences in overall time trends were determined using the Spearman rank correlation and logistic regression models. There were 457 (2004-2005), 550 (2008), and 510 (2011) participants in each study round. There was no significant trend in HIV prevalence over time, and past 12 month unprotected anal intercourse remained steady. However, drug use and number of sex partners declined. Among those who did not self-report being HIV positive, the percentage that tested for HIV in the past 12 months increased. The results from this study suggest that from 2004 through 2011 more MSM in New York City are being tested for HIV and have declining drug use and fewer sex partners.

Assessing the cost effectiveness of pre-exposure prophylaxis for HIV prevention in the US

About 50,000 people are infected with HIV in the US each year and this number has remained virtually the same for the past decade. Yet, in the last few years, evidence from several multinational randomized clinical trials has shown that the provision of antiretroviral drug to uninfected persons (i.e. pre-exposure prophylaxis) reduces the incidence of HIV by about 50 %. However, evidence from cost-effectiveness studies conducted in the US yield widely varying estimates of the cost per quality-adjusted life-year (QALY) gained, and this variation reflects the substantial uncertainty surrounding the determinants of HIV transmission (e.g. adherence rates to prophylactic medications, the average number of sexual partners, the number and types of sexual acts, the viral load of infected partners, and the proportion of contacts where condoms are used), as well as different approaches to translating a reduction in HIV cases into an estimate of the increase in the number of QALYs.

The cost of science : knowledge and ethics in the HIV pre-exposure prophylaxis trials

Over the past decade AIDS research has turned toward the use of pharmacology in HIV prevention, including pre-exposure prophylaxis (PrEP): the use of HIV medication as a means of preventing HIV acquisition in those who do not have it. This paper explores the contradictory reasons offered in support of PrEP-to empower women, to provide another risk-reduction option for gay men-as the context for understanding the social meaning of the experimental trials that appear to show that PrEP works in gay men and heterosexual couples but not single women. The PrEP debates reveal the different ideas about "demedicalization" in the earlier gay health and women's health movements and highlight the relationship between health activism and critique of research ethics in the context of a global pharmaceutical market.