Update on HIV prevention and preexposure prophylaxis.

HIV preexposure prophylaxis (PrEP) is an opportunity for clinicians to curb the 40,000 HIV infections occurring annually in the United States. PrEP is medication used by HIV-negative patients to reduce their risk of acquiring the virus. This article provides a baseline understanding of PrEP indications, prescribing, and monitoring, including a review of previously approved medication and an update on newly approved drugs, including emtricitabine/tenofovir alafenamide (F/TAF). Sexual and gender minorities are often underrepresented in the literature about PrEP, but clinicians should address risk focused on specific behaviors rather than population-level characteristics. As one of few professions with prescriptive authority, PAs have an obligation to understand and manage PrEP.

Comparative Pricing of Branded Tenofovir Alafenamide-Emtricitabine Relative to Generic Tenofovir Disoproxil Fumarate-Emtricitabine for HIV Preexposure Prophylaxis: A Cost-Effectiveness Analysis.

Background: Tenofovir alafenamide-emtricitabine (F/TAF) was recently approved as a noninferior and potentially safer option than tenofovir disoproxil fumarate-emtricitabine (F/TDF) for HIV preexposure prophylaxis (PrEP) in the United States. Objective: To estimate the greatest possible clinical benefits and economic savings attributable to the improved safety profile of F/TAF and the maximum price payers should be willing to pay for F/TAF over generic F/TDF. Design: Cost-effectiveness analysis. Data Sources: Published literature on F/TDF safety (in persons with and those without HIV) and the cost and quality-of-life effects of fractures and end-stage renal disease (ESRD). Target Population: Age-stratified U.S. men who have sex with men (MSM) using PrEP. Time Horizon: Five years. Perspective: Health care sector. Intervention: Preexposure prophylaxis with F/TAF versus F/TDF. Outcome Measures: Fractures averted, cases of ESRD averted, quality-adjusted life-years (QALYs) saved, costs, incremental cost-effectiveness ratios (ICERs), and maximum justifiable price for F/TAF compared with generic F/TDF. Results of Base-Case Analysis: Over a 5-year horizon, compared with F/TDF, F/TAF averted 2101 fractures and 25 cases of ESRD for the 123 610 MSM receiving PrEP, with an ICER of more than $7 million per QALY. At a 50% discount for generic F/TDF ($8300 per year) and a societal willingness to pay up to $100 000 per QALY, the maximum fair price for F/TAF was $8670 per year. Results of Sensitivity Analysis: Among persons older than 55 years, the ICER for F/TAF remained more than $3 million per QALY and the maximum permissible fair price for F/TAF was $8970 per year. Results were robust to alternative time horizons and PrEP-using population sizes. Limitation: Intermittent use and on-demand PrEP were not considered. Conclusion: In the presence of a generic F/TDF alternative, the improved safety of F/TAF is worth no more than an additional $370 per person per year. Primary Funding Source: National Institute of Allergy and Infectious Diseases, National Institute on Drug Abuse, National Institute of Mental Health, and Massachusetts General Hospital Executive Committee on Research.

Cost-effectiveness of preexposure prophylaxis for HIV prevention for conception in the United States.

OBJECTIVE: The aim of this study was to investigate the value of coformulated Tenofovir disoproxil fumarate and emtricitabine (TDF/FTC) for preexposure prophylaxis (PrEP) for conception in the U.S. and to identify scenarios in which 'Undetectable = Untransmittable' (U = U) may not be adequate, and rather, PrEP or assisted reproduction would improve outcomes. DESIGN: We developed a Markov cohort simulation model to estimate the incremental benefits and cost-effectiveness of PrEP compared with alternative safer conception strategies, including combination antiretroviral therapy (cART) alone for the HIV-infected partner and assisted reproductive technologies. We modelled various scenarios in which HIV RNA suppression in the male partner was less than perfect. SETTING: U.S. healthcare sector perspective. PARTICIPANTS: Serodiscordant couples in the U.S. was composed of an HIV-infected male and HIV-uninfected female seeking conception. INTERVENTION: Economic analysis. MAIN OUTCOME MEASURE(S): Cumulative risks of HIV transmission to women and babies, maternal life expectancy, discounted quality-adjusted life years (QALY), discounted lifetime medical costs and incremental cost-effectiveness ratios. RESULTS: cART with condomless intercourse limited to ovulation was the preferred HIV prevention strategy among women seeking to conceive with an HIV-infected partner who is HIV-suppressed. PrEP was not cost-effective for women who had partners who were virologically suppressed. When the probability of male partner HIV suppression was low and we assumed generic pricing of PrEP, PrEP was cost-effective, and sometimes even cost-saving compared with cART alone. CONCLUSION: From a U.S. healthcare sector perspective, when the male partner was not reliably suppressed, PrEP became economically attractive, and in some cases, cost-saving.

Substituting Generic Lamivudine for Emtricitabine in Virologically Suppressed HIV-Infected Patients.

This study evaluated the effectiveness of formulary substitution from products or regimens containing name brand emtricitabine to alternative regimens containing generic lamivudine among virologically suppressed HIV-infected patients in a correctional managed health care system. Results of this retrospective cohort study showed that 94.9% of patients switched from emtricitabine to lamivudine ( n = 447) and 93.0% of emtricitabine control patients ( n = 449) had an undetectable viral load at last available test over a 2-year period. The two groups also showed similar values for CD4 counts, compliance, discontinuation, and M184V mutation; however, a slightly greater proportion of lamivudine patients experienced respiratory symptoms. Nonetheless, this study demonstrates that switching virologically suppressed HIV-infected patients from name brand emtricitabine-containing regimens to generic lamivudine-based regimens may reduce costs without compromising safety or effectiveness in correctional managed health care systems with directly observed therapy.

Cost-effectiveness of pre-exposure prophylaxis for HIV prevention in men who have sex with men in the UK: a modelling study and health economic evaluation.

BACKGROUND: In the UK, HIV incidence among men who have sex with men (MSM) has remained high for several years, despite widespread use of antiretroviral therapy and high rates of virological suppression. Pre-exposure prophylaxis (PrEP) has been shown to be highly effective in preventing further infections in MSM, but its cost-effectiveness is uncertain. METHODS: In this modelling study and economic evaluation, we calibrated a dynamic, individual-based stochastic model, the HIV Synthesis Model, to multiple data sources (surveillance data provided by Public Health England and data from a large, nationally representative survey, Natsal-3) on HIV among MSM in the UK. We did a probabilistic sensitivity analysis (sampling 22 key parameters) along with a range of univariate sensitivity analyses to evaluate the introduction of a PrEP programme with sexual event-based use of emtricitabine and tenofovir for MSM who had condomless anal sexual intercourse in the previous 3 months, a negative HIV test at baseline, and a negative HIV test in the preceding year. The main model outcomes were the number of HIV infections, quality-adjusted life-years (QALYs), and costs. FINDINGS: Introduction of such a PrEP programme, with around 4000 MSM initiated on PrEP by the end of the first year and almost 40 000 by the end of the 15th year, would result in a total cost saving (£1·0 billion discounted), avert 25% of HIV infections (42% of which would be directly because of PrEP), and lead to a gain of 40 000 discounted QALYs over an 80-year time horizon. This result was particularly sensitive to the time horizon chosen, the cost of antiretroviral drugs (for treatment and PrEP), and the underlying trend in condomless sex. INTERPRETATION: This analysis suggests that the introduction of a PrEP programme for MSM in the UK is cost-effective and possibly cost-saving in the long term. A reduction in the cost of antiretroviral drugs (including the drugs used for PrEP) would substantially shorten the time for cost savings to be realised. FUNDING: National Institute for Health Research.

Switching to a rilpivirine/emtricitabine/tenofovir single-tablet regimen in RNA-suppressed patients infected with human immunodeficiency virus 1: Effectiveness, safety and costs at 96 weeks.

OBJECTIVES: This study evaluates the effectiveness, safety and costs of switching to a rilpivirine/emtricitabine/tenofovir disoproxil fumarate (RPV/FTC/TDF) regimen in treatment-experienced HIV-1-infected patients with sustained virological suppression. METHODS: Observational, prospective study. Study population included all treatment-experienced patients with sustained virological suppression who switched to RPV/FTC/TDF during 2013 in a tertiary hospital. Patients were followed until they completed 96 weeks of treatment. The effectiveness end-point was defined as the proportion of patients who maintained virological suppression at week 96 by intention-to-treat analysis (discontinuation=failure). The safety of RPV/FTC/TDF (incidence of adverse events leading to discontinuation and laboratory abnormalities) and adherence to this regimen were evaluated, and the cost of switching was analysed. RESULTS: One-hundred forty-six patients were included. At week 96, 71.9% of patients remained virologically suppressed; 6.8% experienced virological failure. During follow-up, 25.3% of patients discontinued RPV/FTC/TDF (14.4% because of adverse events, mainly renal impairment). Throughout the 96 weeks, there were significant decreases in total cholesterol (TC) (14.0 mg/dL, P<.001), TC/HDL cholesterol ratio (0.4 mg/dL, P=.019) and triglycerides (42.0 mg/dL, P<.001). A slight decrease in glomerular filtration rate was observed (4.3 mL/min/1.73 m2 , P<.001). Switching to RPV/FTC/TDF improved adherence in the subgroup of patients whose previous treatment was based on a twice-daily schedule, although differences did not reach statistical significance. Switching to RPV/FTC/TDF reduced the annual per-patient antiretroviral cost by €1744 (P<.001). CONCLUSIONS: In virologically suppressed patients, the switch to a RPV/FTC/TDF regimen was associated with a mild but maintained improvement in lipid parameters and a significant reduction in costs. However, the relatively high rates of virological failure and treatment discontinuation because of adverse events make this combination a less favourable choice over other regimens currently available.

Cost-effectiveness analysis of pre-exposure prophylaxis for HIV-1 prevention in the Netherlands: a mathematical modelling study.

BACKGROUND: Pre-exposure prophylaxis (PrEP) with tenofovir and emtricitabine prevents HIV infections among men who have sex with men (MSM). PrEP can be given on a daily or intermittent basis. Unfortunately, PrEP is not reimbursed in most European countries. Cost-effectiveness analyses of PrEP among MSM in Europe are absent but are key for decision makers to decide upon PrEP implementation. METHODS: We developed a deterministic mathematical model, calibrated to the well defined Dutch HIV epidemic among MSM, to predict the effect and cost-effectiveness of PrEP. PrEP was targeted to 10% of highly sexually active Dutch MSM over the coming 40 years. Cost-effectiveness ratios were calculated to predict the cost-effectiveness of daily and on-demand PrEP. Cost-effectiveness ratios below €20 000 were considered to be cost-effective in this analysis. FINDINGS: Within the context of a stable HIV epidemic, at 80% effectiveness and current PrEP pricing, PrEP can cost as much as €11 000 (IQR 9400-14 100) per quality-adjusted life-year (QALY) gained when used daily, or as little as €2000 (IQR 1300-3000) per QALY gained when used on demand. At 80% effectiveness, daily PrEP can be considered cost-saving if the price of PrEP is reduced by 70%, and on-demand PrEP can be considered cost-saving if the price is reduced by 30-40%. INTERPRETATION: PrEP for HIV prevention among MSM in the Netherlands is cost-effective. The use of PrEP is most cost-effective when the price of PrEP is reduced through on-demand use or through availability of generic PrEP, and can quickly be considered cost-saving. FUNDING: None.

Preexposure Prophylaxis (PrEP) for HIV Prevention: The Primary Care Perspective.

Until recently there have been few primary care office-based strategies to reduce the transmission of HIV. In May 2014 the Centers for Disease Control and Prevention published updated practice guidelines recommending the use of preexposure prophylaxis (PrEP) with daily oral dosing of tenofovir/emtricitabine to help prevent HIV infection in high-risk individuals (strength of recommendation, A). Knowledge of PrEP among primary care providers is low, however, and this intervention is likely reaching only a small fraction of eligible patients. PrEP is recommended for certain injection drug users, nonmonogamous men who have sex with men, heterosexual women who have sex with men who have sex with men or injection drug users, and those in HIV serodiscordant relationships. Providers should obtain baseline laboratory values and provide initial counseling before prescribing PrEP. Regular office visits are necessary to ensure adherence, provide ongoing counseling, and monitor for side effects, including nausea, abdominal pain, headache, and, less commonly, increased creatinine. Guidelines and toolkits have been developed to assist in incorporating PrEP into primary care practice. PrEP is gaining widespread acceptance and has become a crucial tool in the fight to stop the spread of HIV.

Antiretroviral therapy management and rationalisation of available resources.

The treatment of HIV disease has led to a new division of management costs by shifting most of the necessary resources from inpatient treatment to outpatient management. Among the initiatives aimed at rationalising the resources available, we compared efficacy, tolerability and pharmacoeconomic impact of different regimes of antiretroviral therapy (ART). The survey covered the first 50 patients, clinically stable and with good viro-immunological response, who switched in June 2012 from an ART based on the triple combination of tenofovir (TDF), emtricitabine (FTC) and a protease inhibitor boosted with ritonavir (PI/r) or a non-nucleoside reverse transcriptase inhibitor (NNRTI), to a treatment based on abacavir (ABC), lamivudine (3TC) and a PI/r or NNRTI. Of the 50 patients who operated the switch, 39 replaced a PI with nevirapine (NVP), for which the largest group of patients was treated with ABC + 3TC + NVP. On 31 May 2015, all patients completed the observation period of 96 weeks, with a mean observation period of 132 weeks and clinical-laboratory checks every four months. Laboratory analysis revealed an optimal maintenance of viral suppression and absolute and relative number of CD4 + lymphocytes and improving trend of creatinine, proteinuria, serum phosphate and bone alkaline phosphatase. There was a variable effect on lipids, with a drop in triglycerides associated with a modest increase in total cholesterol. Much of the HIV-positive population reporting to our hospitals (>50%) comprises individuals who have for years been in stable viraemic suppression, making a satisfactory immune recovery while in good overall clinical condition. This type of patient was the target of the present survey. At the end of 96 weeks of observation the new regimes were well tolerated and did not lead to viro-immunological or clinical deterioration. Pharmacoeconomic analysis showed better containment of the overall costs. No patient needed to be hospitalised during the observation period.