Cost-effectiveness of Cabotegravir Long-Acting for HIV Pre-exposure Prophylaxis in the United States.

OBJECTIVE: Cabotegravir long-acting (CAB-LA) administered every 2 months was approved in the USA as pre-exposure prophylaxis (PrEP) for individuals at risk of acquiring human immunodeficiency virus (HIV)-1 infection based on the HIV Prevention Trials Network (HPTN) 083 and HPTN 084 clinical trials, which demonstrated superior reduction in HIV-1 acquisition compared with daily oral emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) in men who have sex with men (MSM), transgender women (TGW), and cisgender women. A decision-analytic model was developed to assess the lifetime cost-effectiveness of initiating CAB-LA versus generic oral FTC/TDF for HIV PrEP in the USA from a healthcare sector perspective. METHODS: PrEP-eligible adults entered the Markov model receiving CAB-LA or FTC/TDF and could continue initial PrEP, transition to a second PrEP option, or discontinue PrEP over time. Efficacy was taken from the HPTN 083 and HPTN 084 clinical trials. Individuals who acquired HIV-1 infection incurred lifetime HIV-related costs, could transmit HIV onwards, and could develop PrEP-related resistance mutations. Input parameter values were obtained from public and published sources. Model outcomes were discounted at 3%. RESULTS: The model estimated that the CAB-LA pathway prevented 4.5 more primary and secondary HIV-1 infections per 100 PrEP users than the oral PrEP pathway, which yielded 0.2 fewer quality-adjusted life-years (QALYs) lost per person. Additional per-person lifetime costs were $9476 (2022 US dollars), resulting in an incremental cost-effectiveness ratio of $46,843 per QALY gained. Results remained consistent in sensitivity and scenario analyses, including in underserved populations with low oral PrEP usage. CONCLUSIONS: Our analysis suggests that initiating CAB-LA for PrEP is cost-effective versus generic daily oral FTC/TDF for individuals at risk of acquiring HIV-1 infection.

Targeted preventive vaccination campaigns to reduce Ebola outbreaks: An individual-based modeling study.

INTRODUCTION: Nonpharmaceutical interventions (NPI) and ring vaccination (i.e., vaccination that primarily targets contacts and contacts of contacts of Ebola cases) are currently used to reduce the spread of Ebola during outbreaks. Because these measures are typically initiated after an outbreak is declared, they are limited by real-time implementation challenges. Preventive vaccination may provide a complementary option to help protect communities against unpredictable outbreaks. This study aimed to assess the impact of preventive vaccination strategies when implemented in conjunction with NPI and ring vaccination. METHODS: A spatial-explicit, individual-based model (IBM) that accounts for heterogeneity of human contact, human movement, and timing of interventions was built to represent Ebola transmission in the Democratic Republic of the Congo. Simulated preventive vaccination strategies targeted healthcare workers (HCW), frontline workers (FW), and the general population (GP) with varying levels of coverage (lower coverage: 30% of HCW/FW, 5% of GP; higher coverage: 60% of HCW/FW, 10% of GP) and efficacy (lower efficacy: 60%; higher efficacy: 90%). RESULTS: The IBM estimated that the addition of preventive vaccination for HCW reduced cases, hospitalizations, and deaths by âˆ¼11 % to âˆ¼25 % compared with NPI + ring vaccination alone. Including HCW and FW in the preventive vaccination campaign yielded âˆ¼14 % to âˆ¼38 % improvements in epidemic outcomes. Further including the GP yielded the greatest improvements, with âˆ¼21 % to âˆ¼52 % reductions in epidemic outcomes compared with NPI + ring vaccination alone. In a scenario without ring vaccination, preventive vaccination reduced cases, hospitalizations, and deaths by âˆ¼28 % to âˆ¼59 % compared with NPI alone. In all scenarios, preventive vaccination reduced Ebola transmission particularly during the initial phases of the epidemic, resulting in flatter epidemic curves. CONCLUSIONS: The IBM showed that preventive vaccination may reduce Ebola cases, hospitalizations, and deaths, thus safeguarding the healthcare system and providing more time to implement additional interventions during an outbreak.

The Cost-Effectiveness and Budget Impact of Ibalizumab-uiyk for Adults with Multidrug-Resistant HIV-1 Infection in the United States.

BACKGROUND: Ibalizumab-uiyk (ibalizumab) is a first-in-class, long-acting, postattachment HIV-1 inhibitor for adults with multidrug-resistant (MDR) HIV-1 infection. This analysis examines the cost-effectiveness and budget impact of ibalizumab treatment for this difficult-to-treat population in the United States. METHODS: A Markov model followed cohorts of adults with MDR HIV-1 infection through two final lines of antiretroviral therapy: ibalizumab + optimized background therapy (OBT) or OBT alone followed by nonsuppressive therapy. Model inputs were based on ibalizumab clinical trial data, market uptake projections, and published literature, with costs in 2019 dollars. The cost-effectiveness analysis assessed costs and health outcomes from a health care sector perspective for individuals receiving ibalizumab + OBT versus OBT alone over a lifetime time horizon. The budget-impact analysis estimated the impact on payer budgets of the introduction of ibalizumab over 3 years for a hypothetical commercial health plan. RESULTS: Compared with individuals receiving OBT alone, individuals receiving ibalizumab + OBT incurred higher costs but lived longer, healthier lives, with an incremental cost of $133,040 per QALY gained. For a hypothetical commercial health plan with 1 million members, the introduction of ibalizumab + OBT was estimated to increase budgets by $217,260, $385,245, and $560,310 ($0.018, $0.032, and $0.047 per member per month) in years 1, 2, and 3, respectively. These results were found to be robust in sensitivity and scenario analyses. CONCLUSIONS: Ibalizumab may represent a cost-effective and affordable option to improve health outcomes for individuals with MDR HIV-1 infection.

Short-term cost analysis of raltegravir versus atazanavir + ritonavir or darunavir + ritonavir for treatment-naive adults with HIV-1 infection in the United States.

METHODS: Ninety-six-week costs for antiretroviral drugs, adverse event management, and HIV care for individuals initiating RAL, ATV/r, or DRV/r as first-line therapy for HIV-1 infection were estimated using an economic model. Efficacy and safety data (mean CD4 cell count changes, discontinuation rates, grade 3/4 adverse event incidence) for each regimen through 96 weeks of treatment were taken from the ACTG 5257 clinical trial. Antiretroviral drug costs for each initial regimen and for each substitution regimen, as used by individuals who discontinued their initial regimen, were based on wholesale acquisition costs. Adverse event management costs and HIV care costs, stratified by CD4 cell count range, were taken from published sources and inflated to 2016 dollars. Scenario and sensitivity analyses were conducted to assess the robustness of the results. Cost outcomes were discounted at an annual rate of 3.0%. RESULTS: Total 96-week costs were $81,231 for RAL, $88,064 for ATV/r, and $87,680 for DRV/r, where differences were primarily due to lower antiretroviral drug costs for RAL than for ATV/r or DRV/r. These results were found to be robust in scenario and sensitivity analyses. CONCLUSIONS: Relative to the DRV/r and ATV/r regimens, the RAL regimen had the lowest cost for treatment-naive adults with HIV-1 infection in the United States.

Short-term cost and efficiency analysis of raltegravir versus atazanavir/ritonavir or darunavir/ritonavir for treatment-naive adults with HIV-1 infection in Spain.

INTRODUCTION: The AIDS Clinical Trial Group (ACTG) 5257 clinical trial showed that raltegravir (RAL) was superior to atazanavir/ritonavir (ATV/r) and darunavir/ritonavir (DRV/r), when used in combination with emtricitabine/tenofovir DF (FTC/TDF), in a 96-week composite endpoint combining virologic efficacy and tolerability for treatment-naive adults with HIV-1 infection. This study aimed to estimate the efficiency associated with these three regimens in Spain. METHODS: An economic model was developed to estimate costs for antiretroviral drugs, adverse event management, and HIV care for individuals initiating first-line therapy. Antiretroviral drug costs were based on hospital costs with mandatory discounts applied. Adverse event management costs and HIV care costs were obtained from published sources and inflated to 2015 euros. Head-to-head efficacy and safety data (discontinuation rates, mean CD4 cell-count changes, adverse event incidence) up to 96 weeks for each regimen were obtained from the clinical trial. The efficiency of each regimen, as measured by the cost per successfully treated patient (i.e. on first-line therapy for 96 weeks), was estimated and examined in sensitivity analyses. All cost outcomes were discounted at 3.0% annually. RESULTS: Total costs per successfully treated patient were €22,377 for RAL, €26,629 for ATV/r, and €23,928 for DRV/r. These results were found to be robust in sensitivity analyses. DISCUSSION: RAL has the lowest cost per successfully treated patient when compared with DRV/r and ATV/r, each used in combination with FTC/TDF, for treatment-naive adults with HIV-1 infection in Spain. This economic evidence complements the clinical benefits of RAL reported in the ACTG 5257 clinical trial.

Cost-effectiveness of seasonal quadrivalent versus trivalent influenza vaccination in the United States: A dynamic transmission modeling approach.

Trivalent inactivated influenza vaccines (IIV3s) protect against 2 A strains and one B lineage; quadrivalent versions (IIV4s) protect against an additional B lineage. The objective was to assess projected health and economic outcomes associated with IIV4 versus IIV3 for preventing seasonal influenza in the US. A cost-effectiveness model was developed to interact with a dynamic transmission model. The transmission model tracked vaccination, influenza cases, infection-spreading interactions, and recovery over 10 y (2012-2022). The cost-effectiveness model estimated influenza-related complications, direct and indirect costs (2013-2014 US$), health outcomes, and cost-effectiveness. Inputs were taken from published/public sources or estimated using regression or calibration. Outcomes were discounted at 3% per year. Scenario analyses tested the reliability of the results. Seasonal vaccination with IIV4 versus IIV3 is predicted to reduce annual influenza cases by 1,973,849 (discounted; 2,325,644 undiscounted), resulting in 12-13% fewer cases and influenza-related complications and deaths. These reductions are predicted to translate into 18,485 more quality-adjusted life years (QALYs) accrued annually for IIV4 versus IIV3. Increased vaccine-related costs ($599 million; 5.7%) are predicted to be more than offset by reduced influenza treatment costs ($699 million; 12.2%), resulting in direct medical cost saving annually ($100 million; 0.6%). Including indirect costs, savings with IIV4 are predicted to be $7.1 billion (5.6%). Scenario analyses predict IIV4 to be cost-saving in all scenarios tested apart from low infectivity, where IIV4 is predicted to be cost-effective. In summary, seasonal influenza vaccination in the US with IIV4 versus IIV3 is predicted to improve health outcomes and reduce costs.

Cost effectiveness of darunavir/ritonavir combination antiretroviral therapy for treatment-naive adults with HIV-1 infection in Canada.

OBJECTIVE: The AntiRetroviral Therapy with TMC114 ExaMined In naive Subjects (ARTEMIS) clinical trial examined the efficacy and safety of two ritonavir-boosted protease inhibitors (PI/r), darunavir/r 800/100 mg once daily (QD) and lopinavir/r 800/200 mg daily, both used in combination with tenofovir disoproxil fumarate/emtricitabine. This study aimed to assess the cost effectiveness of the darunavir/r regimen compared with the lopinavir/r regimen in treatment-naive adults with HIV-1 infection in Canada. METHODS: A Markov model with a 3-month cycle time and six CD4 cell-count-based health states (>500, 351-500, 201-500, 101-200, 51-100, and 0-50 cells/mm(3)) followed a cohort of treatment-naive adults with HIV-1 infection through initial darunavir/r or lopinavir/r combination therapy and a common set of subsequent regimens over the course of their remaining lifetimes. Population characteristics and transition probabilities were estimated from the ARTEMIS clinical trial and other trials. Costs (in 2014 Canadian dollars), utilities, and mortality were estimated from Canadian sources and published literature. Costs and health outcomes were discounted at 5% per year. One-way and probabilistic sensitivity analyses were performed, including a simple indirect comparison of the darunavir/r initial regimen with an atazanavir/r-based regimen. RESULTS: In the base-case lifetime analysis, individuals receiving initial therapy with the darunavir/r regimen experienced 0.25 more quality-adjusted life-years (QALYs) with lower antiretroviral drug costs (-$14,246) and total costs (-$18,402) than individuals receiving the lopinavir/r regimen, indicating that darunavir/r dominated lopinavir/r. In an indirect comparison with an atazanavir/r-based regimen, the darunavir/r regimen remained the dominant choice, but with lower cost savings (-$2,303) and QALY gains (0.02). Results were robust to a wide range of other changes in input parameter values, population characteristics, and modeling assumptions. The probabilistic sensitivity analysis demonstrated that the darunavir/r regimen was cost effective compared with the lopinavir/r regimen in over 86% of simulations for willingness-to-pay thresholds between $0 and $100,000 per QALY gained. CONCLUSIONS: Darunavir/r 800/100 mg QD may be a cost-effective PI/r component of initial antiretroviral therapy for treatment-naive adults with HIV-1 infection in Canada.

Cost-effectiveness of Telaprevir combination therapy for chronic hepatitis C.

OBJECTIVE: To explore the expected long-term health and economic outcomes of telaprevir (TVR) plus peginterferon alfa-2a and ribavirin (PR), a regimen that demonstrated substantially increased sustained virologic response (SVR) compared with PR alone in adults with chronic genotype 1 hepatitis C virus (HCV) and compensated liver disease in the Phase III studies ADVANCE (treatment-naïve patients) and REALIZE (relapsers, partial responders, and null responders to previous PR treatment). STUDY DESIGN: A decision-analytic model was developed to assess the cost-effectiveness of TVR+PR vs. PR in the United States (US). METHODS: Patients first moved through the 72-week decision-tree treatment phase of the model and then entered the cyclic Markov post-treatment phase. Clinical data (patient characteristics, SVR rates, and adverse event rates and durations) were obtained from ADVANCE and REALIZE. Health-state transition probabilities, drug and other costs (in 2012/2013 US dollars), and utility values were obtained from the trials, published studies, and publicly available sources. Outcomes were discounted at 3% per year. RESULTS: Regardless of treatment history, patients receiving TVR+PR were projected to experience fewer liver-disease complications, more life-years, and more quality-adjusted life-years (QALYs) than patients receiving PR. In prior relapsers, TVR+PR was dominant, with lower total medical costs and more QALYs. For the other patient subgroups, incremental costs per QALY gained were between $16,778 (treatment-naïve patients) and $34,279 (prior null responders). Extensive sensitivity analyses confirmed robust model results. CONCLUSIONS: At standard willingness-to-pay thresholds, TVR+PR represents a cost-effective treatment option compared with PR alone for patients with chronic genotype 1 HCV and compensated liver disease in the US. Future analyses are needed to compare TVR+PR with all existing HCV treatment options.

Análisis comparativo de coste-eficacia entre darunavir/ritonavir y otros inhibidores de la proteasa en el tratamiento de la infección por el virus de la inmunodeficiencia humana de tipo 1 en pacientes naïve en España / Comparative cost-effectiveness analysis between darunavir/ritonavir and other protease inhibitors in treatment-naive human immunodeficiency syndrome type 1-infected patients in Spain

INTRODUCCIÓN: Las guías GESIDA proponen pautas preferentes de inicio de tratamiento antirretroviral en pacientes infectados por el VIH. El objetivo de este análisis es comparar los costes y la eficacia de darunavir/r QD frente a otros inhibidores de la proteasa (IP) potenciados recomendados por GESIDA en pacientes naďve. MÉTODOS: Mediante un modelo de coste-eficacia se compararon los IP/r recomendados como pautas preferentes o alternativas en pacientes naďve, junto con un tratamiento de base con 2 ITIAN. La eficacia se midió mediante la respuesta virológica (carga viral < 50 copias/ml) a las 48 semanas ajustada por los niveles basales de carga viral y recuentos de CD4. Para generar la «frontera de eficiencia» y ratios de coste-eficacia se utilizaron los costes espańoles y las tasas de eficacia a las 48 semanas. RESULTADOS: El modelo estimó que el inicio del tratamiento en naďve con darunavir/r QD se mostró como la opción preferente basada en un IP/r más coste-eficaz. El coste medio del TARGA por paciente respondedor era menor para darunavir/r (13.420 €) que para atazanavir/r (14.000 €) o lopinavir/r (13.815 €). Se estimó que darunavir/r sería el IP preferente más eficiente, mientras que atazanavir/r QD y lopinavir/r BID resultarían opciones «dominadas», situándose fuera de la frontera de la eficiencia. Partiendo de un presupuesto fijo de 10 millones de €, se estimó que la pauta de inicio con darunavir/r QD conseguiría un mayor número de pacientes respondedores (745) que con atazanavir/r QD (714) o lopinavir/r BID (724). Al mismo tiempo, darunavir/r QD reduciría el número de pacientes que fracasarían al tratamiento (150) en comparación con atazanavir/r QD (172) o lopinavir/r (286). CONCLUSIONES: Según este modelo, darunavir/r QD es el IP/r preferente más coste-efectivo para el tratamiento de la infección por el VIH-1 basado en IP/r en pacientes naďve en Espańa

INTRODUCTION: GESIDA (AIDS Study Group) has proposed preferred regimens of antiretroviral treatment as initial therapy in HIV infected patients. The objective of this analysis is to compare the costs and effectiveness of darunavir/r QD and other ritonavir-boosted (/r) protease inhibitors (PIs) currently recommended in GESIDA guidelines for treatment-naďve patients. METHODS: A cost-efficacy model compared the boosted PIs recommended as preferred or alternative treatment choices, each used with a nucleoside reverse transcriptase inhibitor backbone. Efficacy was measured by 48-week virological response (viral load < 50 copies/mL) adjusted by baseline viral load and CD4 cell count. To generate efficiency frontiers and cost-efficacy ratios, one-year antiretroviral therapy costs in Spain, and 48-week efficacy values were used. Results The model estimated that starting treatment with darunavir/r QD was the most cost-effective choice compared with the other preferred PI/r based therapies. The average cost per patient with a virological response was lower for darunavir/r QD (13,420€) than for atazanavir/r QD (14,000€), or lopinavir/r BID (13,815€). Among the preferred PI/r-based therapies, darunavir/r QD also was estimated to be the most efficient option for treatment-naďve patients. Atazanavir/r QD and lopinavir/r BID were found to be «dominated» by darunavir/r) and, consequently, were outside the efficiency frontier of PI/r-based first-line treatment. Given a fixed budget of 10 million euros for PI/r-based first-line therapy, the model estimated that darunavir/r QD would yield more responders (745) than atazanavir/r QD (714), or lopinavir/r BID (724). At the same time, darunavir/r QD would reduce the number of individuals failing treatment (150) compared with atazanavir/r QD (172) and lopinavir/r BID (286). CONCLUSIONS: In this model, darunavir/r QD was found to be the most cost-effective choice, among the preferred PI/r-based therapies recommended in the Spanish guidelines for treatment-naïve patients

[Comparative cost-effectiveness analysis between darunavir/ritonavir and other protease inhibitors in treatment-naive human immunodeficiency syndrome type 1-infected patients in Spain]. / Análisis comparativo de coste-eficacia entre darunavir/ritonavir y otros inhibidores de la proteasa en el tratamiento de la infección por el virus de la inmunodeficiencia humana de tipo 1 en pacientes naïve en España.

INTRODUCTION: GESIDA (AIDS Study Group) has proposed preferred regimens of antiretroviral treatment as initial therapy in HIV infected patients. The objective of this analysis is to compare the costs and effectiveness of darunavir/r QD and other ritonavir-boosted (/r) protease inhibitors (PIs) currently recommended in GESIDA guidelines for treatment-naïve patients. METHODS: A cost-efficacy model compared the boosted PIs recommended as preferred or alternative treatment choices, each used with a nucleoside reverse transcriptase inhibitor backbone. Efficacy was measured by 48-week virological response (viral load < 50 copies/mL) adjusted by baseline viral load and CD4 cell count. To generate efficiency frontiers and cost-efficacy ratios, one-year antiretroviral therapy costs in Spain, and 48-week efficacy values were used. RESULTS: The model estimated that starting treatment with darunavir/r QD was the most cost-effective choice compared with the other preferred PI/r based therapies. The average cost per patient with a virological response was lower for darunavir/r QD (13,420€) than for atazanavir/r QD (14,000€), or lopinavir/r BID (13,815€). Among the preferred PI/r-based therapies, darunavir/r QD also was estimated to be the most efficient option for treatment-naïve patients. Atazanavir/r QD and lopinavir/r BID were found to be «dominated¼ by darunavir/r) and, consequently, were outside the efficiency frontier of PI/r-based first-line treatment. Given a fixed budget of 10 million euros for PI/r-based first-line therapy, the model estimated that darunavir/r QD would yield more responders (745) than atazanavir/r QD (714), or lopinavir/r BID (724). At the same time, darunavir/r QD would reduce the number of individuals failing treatment (150) compared with atazanavir/r QD (172) and lopinavir/r BID (286). CONCLUSIONS: In this model, darunavir/r QD was found to be the most cost-effective choice, among the preferred PI/r-based therapies recommended in the Spanish guidelines for treatment-naïve patients.

Cost-effectiveness of combination therapy with etravirine in treatment-experienced adults with HIV-1 infection.

OBJECTIVE: To assess the cost-effectiveness of etravirine (INTELENCE), a novel nonnucleoside reverse transcriptase inhibitor, used in combination with a background regimen that included darunavir/ritonavir, from a Canadian Provincial Ministry of Health perspective. DESIGN: A Markov model with a 3-month cycle time and six health states based on CD4 cell count ranges was developed to follow a hypothetical cohort of treatment-experienced adults with HIV-1 infection through initial and subsequent treatment regimens. METHODS: Costs (in 2009 Canadian dollars), utilities, and HIV-related mortality data for each health state as well as non-HIV-related mortality data were estimated from Canadian sources and published literature. Transition probabilities between health states and first-year hospitalization and mortality rates were derived from clinical trial data. Incremental 1-year costs per additional adult with viral load less than 50 copies/ml at 48 weeks and incremental lifetime costs per quality-adjusted life-year (QALY) gained were estimated using a 5% discount rate. Sensitivity and variability analyses and model validation were performed. RESULTS: Etravirine was associated with an increased probability of achieving less than 50 copies/ml at 48 weeks of 0.205 and an estimated gain of 0.66 discounted (1.48 undiscounted) QALYs over a lifetime. The incremental 1-year cost per additional person with viral load less than 50 copies/ml was $23,862. The lifetime incremental cost per QALY gained was $49,120. For the uncertainty ranges and variability scenarios tested for the lifetime horizon, the cost-effectiveness ratio was between $28,859 and 66,249. CONCLUSION: When compared with optimized standard of care including darunavir/ritonavir, adding etravirine represents a cost-effective option for treatment-experienced adults in Canada.

Cost-effectiveness of nucleoside reverse transcriptase inhibitor pairs in efavirenz-based regimens for treatment-naïve adults with HIV infection in the United States.

OBJECTIVE: To estimate the cost-effectiveness of once-daily tenofovir/emtricitabine compared with twice-daily zidovudine/lamivudine and once-daily abacavir/lamivudine in treatment-naïve adults with HIV-1 infection in the United States. METHODS: A Markov model with four therapy lines and six health states based on CD4(+) cell-count ranges was developed to estimate lifetime costs and health outcomes. Efficacy data (virologic response and CD4(+) cell-count changes) for first-line therapy were from 144-week results of Study 934 comparing tenofovir/emtricitabine with zidovudine/lamivudine and 48-week results of Study CNA30024 comparing abacavir/lamivudine with zidovudine/lamivudine, all in combination with efavirenz. Data from Study CNA30024 for abacavir/lamivudine were adjusted to allow for an indirect comparison with tenofovir/emtricitabine. Subsequent therapy lines were based on likely baskets of antiretroviral therapy recommended by US treatment guidelines. Utility values, mortality rates, and costs (2009 US dollars) were obtained from published sources. Base-case results were tested in sensitivity and variability analyses. RESULTS: Average discounted results showed that individuals using tenofovir/emtricitabine were predicted to remain on first-line therapy for 7.7 years, accrue lifetime costs of $747,327, and experience 15.75 quality-adjusted life-years (QALYs), compared with 6.0 years, $777,090, and 15.68 QALYs for individuals using abacavir/lamivudine and 5.8 years, $778,287, and 15.44 QALYs for individuals using zidovudine/lamivudine. Tenofovir/emtricitabine was cost-effective compared with the other two first-line regimens in more than 75% of all probabilistic sensitivity analysis simulation runs for every willingness-to-pay threshold between $0 and $250,000 per QALY gained. Results were robust in variability and one-way sensitivity analyses. CONCLUSIONS: Tenofovir/emtricitabine was predicted to be more effective and cost-saving compared with abacavir/lamivudine and zidovudine/lamivudine in treatment-naïve adults with HIV-1 infection in the United States.

Comparative cost-efficacy analysis of darunavir/ritonavir and other ritonavir-boosted protease inhibitors for first-line treatment of HIV-1 infection in the United States.

PURPOSE: A comprehensive study comparing the costs and efficacies of darunavir/ritonavir 800/100 mg qd and the other ritonavir-boosted (/r) protease inhibitors (PIs) recommended for treatment-naïve individuals with HIV-1 infection would help health care decision makers identify the value of each boosted PI. METHODS: A cost-efficacy model was developed to compare the five recommended boosted PIs, each used with a tenofovir-based nucleotide/nucleoside reverse transcriptase inhibitor backbone. Efficacy was measured by virologic response (ie, HIV-1 ribonucleic acid < 50 copies/mL) at 48 weeks, based on a systematic review and meta-analysis of recent clinical trials. One-year antiretroviral therapy costs and 48-week efficacy values were used to generate the efficiency frontier and cost-efficacy ratios. RESULTS: Darunavir/r was the most efficacious boosted PI, with an incremental cost-efficacy ratio of $27,390 per additional individual with virologic response, compared with fosamprenavir/r. All other regimens were dominated. Darunavir/r combination therapy also had one of the lowest average costs ($26,287) per individual with virologic response, resulting in a maximal number of individuals successfully treated within a fixed budget. The model results were robust in variability and sensitivity analyses. CONCLUSION: Darunavir/r 800/100 mg qd combination therapy represents a cost-efficacious option for treatment-naïve individuals with HIV-1 infection in the United States.

Oseltamivir for influenza postexposure prophylaxis: economic evaluation for children aged 1-12 years in the U.S.

BACKGROUND: Postexposure prophylaxis (PEP) with oseltamivir (Tamiflu) has been shown to be effective and is approved in children exposed to a case of influenza in a household setting. Given limited healthcare budgets, it is important to understand the costs and cost effectiveness of PEP in children. PURPOSE: This study aims to estimate the cost effectiveness of oseltamivir PEP for children aged 1-12 years in the U.S. METHODS: A decision-tree model with a 1-year time horizon was used to assess the cost effectiveness of oseltamivir PEP for 10 days at approved doses compared with no prophylaxis for children aged 1-12 years who were exposed to a household index case of influenza from the U.S. societal and payer perspectives. Model inputs included U.S. influenza epidemiology data, efficacy data from oseltamivir PEP clinical trials, direct medical resource use and costs for PEP and influenza treatment derived from large U.S. databases, and indirect costs based on caregiver lost productivity. Base-case estimates were tested in extensive sensitivity analyses. RESULTS: For the societal perspective, the model estimated 12,184 fewer cases of influenza per 100,000 children exposed and an incremental cost-effectiveness ratio of $41,452 per quality-adjusted life-year (QALY) gained. Results were most sensitive to the influenza attack rate, PEP protective efficacy, and prescribing patterns for initiating PEP. Probabilistic sensitivity analyses showed that oseltamivir PEP was likely to be cost effective for all willingness-to-pay threshold values above $34,300 per QALY gained. Results were similar for the payer perspective. CONCLUSIONS: Although there is no official cost-effectiveness threshold in the U.S., results from the current study show that when compared with no prophylaxis, oseltamivir PEP for children has cost-effectiveness ratios similar to those of vaccines for preventing influenza.

Cost-effectiveness of treating influenzalike illness with oseltamivir in the United States.

PURPOSE: The cost-effectiveness of treating influenzalike illness (ILI) with oseltamivir in the United States was assessed. METHODS: A decision-analysis model was developed with a one-year time horizon to assess the cost-effectiveness of oseltamivir compared with usual care from societal and payer perspectives for four patient populations: high-risk adults, healthy adults, elderly adults, and children. The model used efficacy data from oseltamivir clinical trials and other published literature and assumed oseltamivir was effective only in individuals infected with influenza virus not resistant to oseltamivir and treated within 48 hours of symptom onset. Direct medical costs were based on resources used; indirect costs were estimated based on time lost from work due to illness and premature mortality. Base-case estimates were tested in one-way sensitivity and variability analyses. RESULTS: From a societal perspective, oseltamivir was cost-effective across all populations modeled, with an incremental cost per quality-adjusted life-year gained of $5,388, $6,317, $7,652, and $16,176 for high-risk adults, children, elderly adults, and healthy adults, respectively. Results were similar from a payer perspective. When indirect costs were included (for all populations except elderly adults), oseltamivir was cost saving. In sensitivity analyses, oseltamivir remained cost-effective across all patient populations for all values tested, except the probability of developing influenza-related pneumonia. Variability analyses showed that oseltamivir remained cost-effective under most scenarios tested. CONCLUSION: Base-case results and sensitivity analyses from a decision-analysis model found that treatment of ILI with oseltamivir was cost-effective compared with usual care from U.S. payer and societal perspectives in all patient populations studied when only direct costs were considered.

Cost-effectiveness model for neovascular age-related macular degeneration: comparing early and late treatment with pegaptanib sodium based on visual acuity.

OBJECTIVE: To compare the cost-effectiveness of pegaptanib and usual care within three distinct cohorts of subfoveal neovascular age-related macular degeneration (NV-AMD) patients, that is, those with early, moderate, and late disease, using a comprehensive economic model. METHODS: A Markov framework was used to model lifetime movement of a subfoveal NV-AMD cohort through health states based on visual acuity. The model takes a US payer perspective of patients over the age of 65 years. Clinical efficacy was based on published results for the 0.3 mg pegaptanib and usual care groups. Expert interviews were conducted to determine adverse event treatment patterns and vision rehabilitation resource use. Incidence and costs of comorbidities such as depression and fractures associated with the effects of declining visual acuity were based on our previously published analysis of Medicare data. Transition probabilities were derived from published clinical trial data for each 3-month cycle. Utilities were derived from published sources. Three runs of the model were conducted with cohorts of newly diagnosed patients. Patients were classified as having early, moderate, or late NV-AMD defined as visual acuity in the better-seeing eye of 20/40 to more than 20/80, 20/80 to more than 20/200, and 20/200 to more than 20/400, respectively. Costs and outcomes were discounted 3.0% per annum. RESULTS: Incremental costs per vision-year gained and per quality-adjusted life-year (QALY) gained for early NV-AMD patients were approximately one-third those of patients with late disease ($15,279 vs. $57,230 and $36,282 vs. $132,381, respectively). On average, patients treated early with either pegaptanib or usual care incurred lower lifetime total direct costs than those treated later. Sensitivity analysis showed that base-case incremental costs per QALY gained for pegaptanib versus usual care were relatively robust. CONCLUSIONS: For patients with subfoveal NV-AMD, treatment with pegaptanib should be started as early as possible to maximize the clinical and economic benefits.