Cost-effectiveness and budget impact of dolutegravir/lamivudine for treatment of human immunodeficiency virus (HIV-1) infection in the United States

BACKGROUND: Dolutegravir(DTG)/lamivudine(3TC) is the first 2-drug regimen recommended as an initial treatment for people living with HIV (PLHIV). OBJECTIVE: To assess the cost-effectiveness and potential budget impact of DTG/3TC in the US healthcare setting. METHODS: A previously published hybrid decision-tree and Markov cohort state transition model was adapted to estimate the incremental costs and health outcome benefits over a patients' lifetime. DTG/3TC was compared with current standard of care in treatment naive and treatment experienced virologically suppressed PLHIV. Health states included in the model were based upon virologic response and CD4 cell count, with death as an absorbing state. Clinical data was informed by the Phase III GEMINI 1 and 2 clinical trials, a published network meta-analysis (NMA) in treatment-naive patients and the Phase III TANGO clinical trial in treatment experienced patients. Costs and utilities were informed by published data and discounted annually at a rate of 3%. A separate 5-year budget impact analysis was conducted assuming 5%-15% uptake in eligible treatment naive and 10%-30% uptake in eligible treatment experienced patients. RESULTS: In the treatment naive analyses based on GEMINI 1 and 2, DTG/3TC dominated, i.e., was less costly and more effective, than all comparators. DTG/3TC resulted in 0.083 incremental quality-adjusted life-years (QALYs) at a cost saving of $199,166 compared with the DTG + tenofovir disoproxil(TDF)/emtricitabine(FTC) comparator arm. The incremental QALY and cost savings for DTG/3TC compared with DTG/abacavir(ABC)/3TC, cobicistat-boosted darunavir(DRV/c)/tenofovir alafenamide(TAF)/FTC, and bictegravir (BIC)/TAF/FTC, based on NMA results were 0.465, 0.142, and 0.698, and $42,948, $122,846, and $44,962, respectively. In the analyses of treatment-experienced virologically suppressed patients based on TANGO, DTG/3TC offered slightly lower QALYs (-0.037) with an estimated savings of $78,730 when compared with continuation of TAF-based regimen (TBR). Sensitivity analyses demonstrated that these conclusions were relatively insensitive to alternative parameter estimates. The budget impact analysis estimated that by 5th year a total of 70,240 treatment naive patients and 1,340,480 treatment experienced patients could be eligible to be prescribed DTG/3TC. The estimated budget savings over 5 years ranged from $1.12b to $3.35b (corresponding to 27,512 to 82,536 on DTG/3TC by year 5) in the lowest and highest uptake scenarios, respectively. CONCLUSION: In conclusion, DTG/3TC with its comparable efficacy and lower drug acquisition costs, has the potential to offer significant cost savings to US healthcare payers for the initial treatment of treatment naive patients and as a treatment switching option for virologically suppressed patients. DISCLOSURES: This study was funded in full by ViiV healthcare, Brentford, UK. Medical writing to support this study was also funded in full by ViiV Healthcare, Brentford, UK. Butler, Hayward, and Jacob are employees of HEOR Ltd, the company performing this study funded by ViiV Healthcare. Anderson is an employee of GlaxoSmithKline and owns shares in the company. Punekar, Evitt, and Oglesby are employees of ViiV Healthcare and own stocks in GlaxoSmithKline.

Estimating HIV Management and Comorbidity Costs Among Aging HIV Patients in the United States: A Systematic Review

BACKGROUND

As life expectancy of patients infected with human immunodeficiency virus (HIV) approaches that of the general population, the composition of HIV management costs is likely to change.

OBJECTIVES

To (a) review treatment and disease management costs in HIV, including costs of adverse events (AEs) related to antiretroviral therapy (ART) and long-term toxicities, and (b) explore the evolving cost drivers.

METHODS

A targeted literature review between January 2012 and November 2017 was conducted using PubMed and major conferences. Articles reporting U.S. costs of HIV management, acquired immunodeficiency syndrome (AIDS)-defining events, end of life care, and ART-associated comorbidities such as cardiovascular disease (CVD), chronic kidney disease (CKD), and osteoporosis were included. All costs were inflated to 2017 U.S. dollars. A Markov model-based analysis was conducted to estimate the effect of increased life expectancy on costs associated with HIV treatment and management.

RESULTS

22 studies describing HIV costs in the United States were identified, comprising 16 cost-effectiveness analysis studies, 5 retrospective analyses of health care utilization, and 1 cost analysis in a resource-limited setting. Management costs per patient per month, including routine care costs (on/off ART), non-HIV medication, opportunistic infection prophylaxis, inpatient utilization, outpatient utilization, and emergency department utilization were reported as CD4+ cell-based health state costs ranging from $1,192 for patients with CD4 > 500 cells/mm3 to $2,873 for patients with CD4 < 50 cells/mm3. Event costs for AEs ranged from $0 for headache, pain, vomiting, and lipodystrophy to $31,545 for myocardial infarction. The mean monthly per-patient costs for CVD management, CKD management, and osteoporosis were $5,898, $6,108, and $4,365, respectively. Improvements in life expectancy, approaching that of the general population in 2018, are projected to increase ART-related and AE costs by 35.4% and comorbidity costs by 175.8% compared with estimated costs with HIV life expectancy observed in 1996.

CONCLUSIONS

This study identified and summarized holistic cost estimates appropriate for use within U.S. HIV cost-effectiveness analyses and demonstrates an increasing contribution of comorbidity outcomes, primarily associated with aging in addition to long-term treatment with ART, not typically evaluated in contemporary HIV cost-effectiveness analyses.

DISCLOSURES

This analysis was sponsored by ViiV Healthcare, which had no role in the analyses and interpretation of study results. Ward, Sugrue, Hayward, and McEwan are employees of HEOR Ltd, which received funding from ViiV Healthcare to conduct this study. Anderson is an employee of GlaxoSmithKline and holds shares in the company. Punekar and Oglesby are employees of ViiV Healthcare and hold shares in GlaxoSmithKline. Lopes was employed by ViiV Healthcare at the time of the study and holds shares in GlaxoSmithKline.

Cost-effectiveness of CYP2B6 genotyping to optimize efavirenz dosing in HIV clinical practice

AIMS

To assess the cost-effectiveness of CYP2B6 genotyping to guide efavirenz dosing for initial HIV therapy in the USA.

METHODS

We used the Cost-Effectiveness of Preventing AIDS Complications (CEPAC) microsimulation model to project quality-adjusted life expectancy and lifetime costs (2014 US dollars) for efavirenz-based HIV therapy with or without CYP2B6 genotyping. We assumed that with genotyping 60% of patients would be eligible to receive lower doses.

RESULTS

Current care without CYP2B6 genotyping has an incremental cost-effectiveness ratio >$100,000/QALY compared with genotype-guided dosing, even if lower dosing reduces efficacy. When we assumed generic efavirenz availability, conclusions were similar unless lower dosing reduces efficacy by 6% or more.

CONCLUSION

CYP2B6 genotyping can inform efavirenz dosing and decrease HIV therapy cost.

The lifetime medical cost savings from preventing HIV in the United States

OBJECTIVE

Enhanced HIV prevention interventions, such as preexposure prophylaxis for high-risk individuals, require substantial investments. We sought to estimate the medical cost saved by averting 1 HIV infection in the United States.

METHODS

We estimated lifetime medical costs in persons with and without HIV to determine the cost saved by preventing 1 HIV infection. We used a computer simulation model of HIV disease and treatment (CEPAC) to project CD4 cell count, antiretroviral treatment status, and mortality after HIV infection. Annual medical cost estimates for HIV-infected persons, adjusted for age, sex, race/ethnicity, and transmission risk group, were from the HIV Research Network (range, $1854-$4545/mo) and for HIV-uninfected persons were from the Medical Expenditure Panel Survey (range, $73-$628/mo). Results are reported as lifetime medical costs from the US health system perspective discounted at 3% (2012 USD).

RESULTS

The estimated discounted lifetime cost for persons who become HIV infected at age 35 is $326,500 (60% for antiretroviral medications, 15% for other medications, 25% nondrug costs). For individuals who remain uninfected but at high risk for infection, the discounted lifetime cost estimate is $96,700. The medical cost saved by avoiding 1 HIV infection is $229,800. The cost saved would reach $338,400 if all HIV-infected individuals presented early and remained in care. Cost savings are higher taking into account secondary infections avoided and lower if HIV infections are temporarily delayed rather than permanently avoided.

CONCLUSIONS

The economic value of HIV prevention in the United States is substantial given the high cost of HIV disease treatment.

Performance of a mathematical model to forecast lives saved from HIV treatment expansion in resource-limited settings

BACKGROUND

International guidelines recommend HIV treatment expansion in resource-limited settings, but funding availability is uncertain. We evaluated the performance of a model that forecasts lives saved through continued HIV treatment expansion in Haiti.

METHODS

We developed a computer-based, mathematical model of HIV disease and used incidence density analysis of patient-level Haitian data to derive model parameters for HIV disease progression. We assessed the internal validity of model predictions and internally calibrated model inputs when model predictions did not fit the patient-level data. We then derived uncertain model inputs related to diagnosis and linkage to care, pretreatment retention, and enrollment on HIV treatment through an external calibration process that selected input values by comparing model predictions to Haitian population-level data. Model performance was measured by fit to event-free survival (patient level) and number receiving HIV treatment over time (population level).

RESULTS

For a cohort of newly HIV-infected individuals with no access to HIV treatment, the model predicts median AIDS-free survival of 9.0 years precalibration and 6.6 years postcalibration v. 5.8 years (95% confidence interval, 5.1-7.0) from the patient-level data. After internal validation and calibration, 16 of 17 event-free survival measures (94%) had a mean percentage deviation between model predictions and the empiric data of <6%. After external calibration, the percentage deviation between model predictions and population-level data on the number on HIV treatment was <1% over time.

CONCLUSIONS

Validation and calibration resulted in a good-fitting model appropriate for health policy decision making. Using local data in a policy model-building process is feasible in resource-limited settings.

Cost-effectiveness analysis of UGT1A1 genetic testing to inform antiretroviral prescribing in HIV disease

BACKGROUND

Homozygosity for UGT1A1*28/*28 has been reported to be associated with atazanavir-associated hyperbilirubinaemia and premature atazanavir discontinuation. We assessed the potential cost-effectiveness of UGT1A1 testing to inform the choice of an initial protease-inhibitor-containing regimen in antiretroviral therapy (ART)-naive individuals.

METHODS

We used the Cost-Effectiveness of Preventing AIDS Complications computer simulation model to project quality-adjusted life years (QALYs) and lifetime costs (2009 USD) for atazanavir-based ART with or without UGT1A1 testing, using darunavir rather than atazanavir when indicated. We assumed the UGT1A1-associated atazanavir discontinuation rate reported in the Swiss HIV Cohort Study (a *28/*28 frequency of 14.9%), equal efficacy and cost of atazanavir and darunavir and a genetic assay cost of $107. These parameters, as well as the effect of hyperbilirubinaemia on quality of life and loss to follow up, were varied in sensitivity analyses. Costs and QALYs were discounted at 3% annually.

RESULTS

Initiating atazanavir-based ART at CD4(+) T-cell counts <500 cells/μl without UGT1A1 testing had an average discounted life expectancy of 16.02 QALYs and $475,800 discounted lifetime cost. Testing for UGT1A1 increased QALYs by 0.49 per 10,000 patients tested and was not cost-effective (>$100,000/QALY). Testing for UGT1A1 was cost-effective (<$100,000/QALY) if assay cost decreased to $10, or if avoiding hyperbilirubinaemia by UGT1A1 testing reduced loss to follow-up by 5%. If atazanavir and darunavir differed in cost or efficacy, testing for UGT1A1 was not cost-effective under any scenario.

CONCLUSIONS

Testing for UGT1A1 may be cost-effective if assay cost is low and if testing improves retention in care, but only if the comparator ART regimens have the same drug cost and efficacy.