Cost-effectiveness of lopinavir/ritonavir versus nelfinavir as the first-line highly active antiretroviral therapy regimen for HIV infection

PURPOSE

Selecting the optimal treatment regimen for antiviral-naive patients may be difficult, given the concern about the antiviral activity, the development of drug resistance, and the increase in drug costs. This study evaluates the costs and effectiveness of using lopinavir/ritonavir (LPV/r) vs. nelfinavir (NFV), both coadministered with stavudine and lamivudine, as the first HAART regimen in treating HIV patients, based on the results from the published clinical trial M98-863.

METHOD

A Markov model was developed using a combination of viral load (VL) and CD4 count as surrogate markers to define health states. VL and CD4 count data from the 48-week analysis of the clinical trial were used as measures of effect. The impact of resistance difference between NFV and LPV/r was also examined.

RESULTS

Over the first 5 years, the model estimated that LPV/r could save $3,461 USD per patient in total HIV care costs compared with NFV. If the resistance advantage of LPV/r was taken into account, the cost savings by LPV/r increased to $5,546 USD. For longer term projection, without considering the resistance difference, the incremental cost-effectiveness ratio (CER) for LPV/r vs. NFV was $6,653 USD per quality-adjusted life-year (QALY). This CER compares favorably to therapies for HIV disease and for common drug treatments for other conditions and is well within accepted thresholds for health policy makers.

CONCLUSION

When treatment options are being considered, this study suggests that use of LPV/r in the first antiretroviral regimen, as compared to NFV, is cost-effective based on improved efficacy and resistance.

Backlash over ritonavir price hike

On December 3, 2003, Abbott Laboratories, the pharmaceutical company that makes lopinavir (Kaletra), announced that it was going to raise the price of its other anti-HIV drug, ritonavir (Norvir), from $2.14 to $10.72 per capsule in the U.S.--an increase of 400%. (These prices reflect the Average Wholesale Price, or AWP, a national average of list prices charged by wholesalers to pharmacies.)

Abbott Laboratories increases Norvir price fivefold

On December 4, Abbott Laboratories increased the price of tis drug Norvir fivefold--possibly the largest out-of-the-blue overnight price increase for a life-critical medicine in history.

Recent developments in antiretroviral therapy

This article reviews the antiretroviral medications in development as presented at the Eighth Annual Conference on Retroviruses and Opportunistic Infections. New medications for the treatment of HIV/AIDS are discussed by classification and a brief description of its unique quality is described.

The AIDS drug assistance programs and coverage of HIV-related medications

BACKGROUND

AIDS drug assistance programs (ADAPs) have been implemented in each state to facilitate access to medications for low-income, uninsured, and underinsured people with HIV disease. Policies for each ADAP differ, and these differences influence the access people with HIV have to medications.

OBJECTIVE

To compare the coverage of medications and sources of program funding for the state ADAPs.

DESIGN

A self-administered mailed survey, sent to administrators of the 50 state ADAPs and the District of Columbia ADAP in December 1998.

RESULTS

Forty-nine of the 51 ADAPs (96%) responded to the survey. Title II of the Ryan White Comprehensive AIDS Resources Emergency Act provided a large majority of the funding for the ADAPs, with a number of states also using state funds and/or Title I funds for their programs. The formularies of all ADAPs were nearly identical with respect to coverage of antiretrovirals, but differed in the number and types of other medications included. Some states limited access to medications through waiting lists, enrollment caps, and other policies. Sixteen ADAPs reported that the coverage of protease inhibitors resulted in an appropriation of state government funds to their ADAP, while eight states reported an ADAP budget shortfall. In general, ADAPs in poorer and more rural states included a fewer number of medications on their formularies.

CONCLUSIONS

Access to antiretrovirals and other medications is available through state ADAPs, but may be limited in some states due to waiting lists, controls on the enrollment of new beneficiaries, and policies on the number and types of medications beneficiaries may receive.

Economic analysis of initial HIV treatment. Efavirenz- versus indinavir-containing triple therapy

OBJECTIVE

To compare the clinical and economic outcomes associated with triple therapy containing efavirenz or indinavir and 2 nucleoside reverse transcriptase inhibitors (NRTIs; zidovudine and lamivudine) in HIV-positive patients.

DESIGN AND SETTING

An economic model based on viral load and CD4+ cell counts to predict long term outcomes such as progression to AIDS and AIDS-related death was developed and then analysed using data from a randomised clinical trial. Cost estimates from the healthcare system perspective were based on data from 6 state, all-payor databases, the AIDS Cost and Services Utilisation Study, and other literature. Analyses were carried out for time horizons between 5 and 15 years.

PATIENTS AND INTERVENTIONS

HIV-positive patients with limited exposure to NRTIs. Initial regimens consisted of efavirenz or indinavir, each combined with 2 NRTIs. A maximum of 2 switches to other regimens was permitted.

MAIN OUTCOME MEASURES AND RESULTS

The efavirenz-containing triple therapy regimen was predicted to prolong survival at a savings of up to 10,923 US dollars (1998 values) relative to initial therapy with the indinavir-containing regimen. Patients who receive efavirenz are expected to have 11% greater survival at 5 years and fewer treatment failures (28 vs 52%, at 2 years). Overall, the economic and health benefits predicted for the efavirenz-containing regimen were robust to reasonable variation in key parameters.

CONCLUSIONS

The superior clinical trial outcomes for efavirenz-containing regimens should translate into substantial economic and health benefits.

Economic impact of HIV protease inhibitor therapy in the global use of health-care resources

OBJECTIVE

To evaluate the clinical and economical impact of the introduction of HIV protease inhibitor (PI) therapy in the current clinical care of HIV-infected patients.

METHODS

Cohort study with 155 HIV-infected patients with a full year of follow-up before and after the introduction of PI by June 1998. The setting was a large urban tertiary teaching hospital in Madrid, Spain. The main outcomes measures were clinical and immunological evolution, pharmacy, out-patient, emergency room and in-patient medical costs evaluated by diagnostic-related group classification, and the global economic costs of clinical care in HIV-infected patients (AIDS and non-AIDS).

RESULTS

The cost of PI therapy was compensated fully by savings related to reduction of the number, length and severity of hospital admissions in AIDS cases. In contrast, more modest clinical effects with increased costs were observed in non-AIDS cases. Globally, there was an increase of about 20% in the total health-care costs of HIV-infected patients (P < 0.01).

CONCLUSIONS

PI therapy is highly cost-effective in AIDS patients. Its value in less severely immunosuppressed patients requires further evaluation.

Kaletra (ABT-378/r) approved

Details and information sources on Kaletra (lopinavir plus low-dose ritonavir), a protease inhibitor approved last week.

[Antiretroviral therapy in HIV infection. Effects of the introduction of new drugs on health care expenditures, 1994-1999]

The administration of antiretroviral compounds to our cohort of HIV-infected patients was assessed since 1994, on the ground of some epidemiological, clinical, and therapeutic variables. During the six-year study period, a significant increase of mean prescription rate of overall anti-HIV agents was observed, with a nearly 10-fold rise of mean prescribed daily doses per 1,000 patients-year. In particular, lamivudine and indinavir represented the most frequently administered drugs, among nucleoside analogues and protease inhibitors, respectively. A significant increase of the percentage of HIV-infected patients undergoing combined antiretroviral therapy (79.3% in 1999), and the mean number of drugs prescribed per patient (3.02 in 1999), was concurrently detected. The progressive changes of antiretroviral therapy guidelines were responsible for a nearly 16-fold increase of expenditures directly related to antiretroviral drug administration in 1999 compared with 1994 (with over 41% of costs related to protease inhibitors). On the other hand, a substantial modification of HIV disease evolution occurred in our patient cohort in terms of absolute morbidity and mortality figures, as expressed by a drop of notified AIDS cases and AIDS-related deaths ranging from 2.5 to 5 times, during the considered period.

Hospitalizations and costs of treatment for protease inhibitor-based regimens in patients with very advanced HIV-infection (CD4 < 50/mm(3))

PURPOSE

To describe the cost of hospitalization and treatment in patients with very advanced disease who tart different regimens based on a protease inhibitor (PI).

METHOD

An observational retrospective analysis was performed on data from a 48-week randomized, multicenter study. Analysis was based on a subgroup of centers that were geographically defined. Costs of ordinary hospital admissions and of antiretroviral treatment were considered. Incidence of hospitalization and number of days free from hospitalization during the period of observation were calculated. Cost and hospitalization measures were compared among patients receiving three different therapeutic regimens: only PI, PI plus one nucleoside, or PI plus two nucleosides. A multivariate analysis was used to assess cost differences, controlling for variables potentially able to influence outcome.

RESULTS

Overall, among 166 patients starting PI (PI plus two nucleosides, 71;PI plus one nucleoside, 65; only PI, 30), 162 ordinary hospital admissions were observed during about 1 year of follow-up. Monthly rates of admission per person and incidence of first hospitalization on 100 person-months showed a clear inverse relationship with the number of drugs comprising the baseline treatment regimen, with the lower rates for the triple therapy group (0.06 and 3.9, respectively), intermediate values for the dual therapy group (0.10 and 8.1, respectively), and higher rates for the PI monotherapy group (0.15 and 13.7, respectively). The average number of days free from hospitalization per month was 29.5 in the triple therapy group, 28.6 in the dual therapy group, and 27.9 in the monotherapy group. The results of cost analysis showed, despite higher cost of antiretroviral treatment, that global costs were progressively lower using regimens of increasing potency: Compared to PI monotherapy, global cost (costs of antiretroviral treatment and of hospitalizations combined) per month per patient was 31.9% lower for the triple therapy group and 19.3% lower for the dual therapy. Global cost for the triple therapy was 15.7% lower compared to global cost for dual therapy. After adjustment for CD4 count, AIDS status, and Karnofsky score, both hospitalization costs and global costs were significantly lower for triple therapy compared to monotherapy (p =.002 and.039, respectively).

CONCLUSION

In advanced and nucleoside-experienced patients, PI-containing regimens have a differential impact according to the overall strength of the regimen, with the best effects on both hospitalizations and treatment costs obtained using PI within potent combination regimens.

Reduction in hospitalization costs, morbidity, disability, and mortality in patients with aids treated with protease inhibitors

BACKGROUND

The objective of this study was to analyze hospitalization costs, morbidity, disability, and mortality in patients with acquired immunodeficiency syndrome (AIDS) treated with protease inhibitors (PI).

METHODS

This is a self-controlled, ambispective study of a total of 581 patients with human immunodeficiency virus (HIV)/AIDS seen at the Hospital de Infectología, Centro Médico La Raza, IMSS, in Mexico City during 1997. A total of 210 (36.14%) patients initiated protease inhibitor (PI) treatment at the onset of the study. Thirty-eight patients satisfied the inclusion criteria for this study and were analyzed retrospectively during the year prior to PI treatment, and then prospectively throughout the year on PI treatment. As concerns main outcome measures, financial costs, number of hospitalizations, number of infections, and productivity and laboratory parameters (CD4(+) counts and viral load) were analyzed during the year prior to PI treatment and then prospectively during the year on PI prescription. Our hypothesis was that the hospital costs, morbidity, disability, and mortality of patients with AIDS decreased while on PI treatment.

RESULTS

During the year prior to PI prescription, the 38 patients enrolled in the study were admitted on a total of 59 occasions (1.55 hospitalizations/patient), whereas during the year on PI therapy, all 38 patients had only seven admissions (0.18 hospitalizations/patient). Hospitalization costs decreased 35% when annual PI costs for the 38 patients studied were taken into account. The number of microorganisms detected during hospitalization decreased from 24 prior to PI to five on PI. The number of disability days involved in patients on PI decreased significantly (p <0.0002). None of the 38 patients studied died during the year of follow-up under PI treatment. Mortality decreased significantly, from 116/481 (23.2%) in 1996, to 77/581 (13.2%) in 1997, to 40/740 (6.4%) in 1998. There were no deaths among the 38 patients studied during the 1-year follow-up period; when the observation period was extended 1 additional year, only one patient died (2.63%). Only six (3.48%) of the 172 PI-treated patients with AIDS not included in the study died during the same period. CD4(+) cell counts increased from 190.56 +/- 169.5 cells/mm(3) to 235.00 +/- 112.65 cells/mm(3) (p <0.05) after 12 months of PI treatment. Viral loads decreased from 5 logs to 2.4 logs at 12 months of PI treatment (p <0.001).

CONCLUSIONS

Introduction of PI to antiretroviral treatment in patients with AIDS was associated with a lower rate of hospital admissions, lower costs, and a lesser number of infections/year, disabilities, and mortalities. Increase of CD4(+) cell counts and decrease in viral loads in the 38 patients were associated with decreased morbility and mortality.

Impact of zidovudine-based triple combination therapy on an AIDS drug assistance program

A static deterministic model was used to estimate the effect of the shift to a triple combination therapeutic standard on the annual AIDS Drug Assistance Program (ADAP) budget, total medical care expenditures, and population health outcomes for New York (NY) state ADAP enrollees. The model used opportunistic disease incidence data from the Multicenter AIDS Cohort Study (MACS) and other studies. Costs of treating opportunistic infections (OIs) and other HIV complications with each type of therapy were derived from treatment algorithms and standard unit costs. CD4+ cell counts were used as an index of need for OI prophylaxis and for determining OI incidence. Treatment with zidovudine-based combination therapy has been shown to increase CD4+ cell counts and reduce OI incidence. The model estimated that a change from monotherapy to triple therapy would have increased NY ADAP budget expenditures per enrollee by 115%. However, total medical system costs per ADAP enrollee (including ADAP costs) would decrease by 0.4% in the base case as a result of reduction in OIs and other HIV sequelae and associated costs. Results are sensitive to the assumed percentage of people taking combination therapy as well as to the assumptions made about the impact of the combination therapy on CD4+ cell count. Total ADAP budget impacts will depend on the growth in ADAP enrollment as a result of the availability of more effective therapies. In conclusion, this model demonstrates how access to newer, more effective HIV drug treatments can reduce the costs of treating OIs and provide major health benefits for ADAP enrollees.

Reduction in human immunodeficiency virus patient hospitalizations and nontraumatic mortality after adoption of highly active antiretroviral therapy

Highly active antiretroviral therapy (HAART) has been recommended for human immunodeficiency virus (HIV)-positive patients with a detectable viral load; it typically consists of two reverse transcriptase inhibitors combined with a protease inhibitor. In 1996, Madigan Army Medical Center began offering HAART to HIV-positive patients with a detectable viral load. We retrospectively reviewed the records of our HIV patients before and after the initiation of HAART to determine the impact of HAART on hospitalizations, mortality, and outpatient pharmacy expenditures. Comparing 1997 with 1994 and 1995, we found a greater than 700% increase in the average expenditure on antiretroviral agents after institution of HAART. At the same time, we found a dramatic reduction in hospitalizations and nontraumatic mortality. Therefore, the increase in expenditures on antiretroviral agents may be offset by a reduction in hospitalizations and mortality.

What every health care professional should know about AIDS

As more and more clients with acquired immunodeficiency syndrome (AIDS) are encountered in health care agencies, it is important that the health care professional be well informed with current facts and information on treatment. Supportive care by the health professional is essential to assist the client in maintaining maximum quality of life and a sense of self-esteem and self-efficacy. It is important for the professional to be aware not only of the supportive care needed by clients but also of the safeguards necessary in such a high-risk profession.

Changing cost of English HIV service provision 1996-1997. NPMS Steering Group. National Prospective Monitoring System

The objectives of this study were to provide individual and population-based unit cost estimates of HIV treatment and care by stage of HIV infection for adults in England and estimate the financial impact of the use of combination antiretroviral therapy. Individual unit cost estimates were calculated, based on 1997 activity data, and linked to the number of diagnosed HIV-infected individuals using statutory medical services by clinical stage of HIV infection in England during 1997 to obtain population-based cost estimates; these were compared with 1996 estimates. Most clinical guidelines now recommend the use of 3 antiretroviral agents, but cost estimates for mono and dual therapy were included as baseline estimates. Baseline costs for treating AIDS patients with zidovudine (AZT) monotherapy were estimated at pound sterling 16,830 (95% CI 14,633-18,985) per patient-year which was substantially lower than the 1996 estimate; costs for asymptomatic individuals and people with symptomatic non-AIDS were pound sterling 4450 (95% CI 3521-5612) and pound sterling 7289 (95% CI 6169-8386) per respective patient-year which did not differ substantially from 1996. The total annual population cost estimate for HIV service provision amounted to pound sterling 128 million (95% CI pound sterling 109m to pound sterling 147m), if all patients with HIV disease were treated with AZT monotherapy only. For all eligible patients to be treated with 2 nucleoside reverse transcriptase inhibitors (NRTI) (AZT and didanosine (ddI) or zalcitabine (ddC)), cost estimates amounted to pound sterling 161m (95% CI pound sterling 141m to pound sterling 181m), while for triple therapy, annual estimated expenditure amounted to pound sterling 185m (95% CI pound sterling 165m to pound sterling 206m) when a non-nucleoside reverse transcriptase inhibitor (NNRTI) (nevirapine) was included or pound sterling 205m (95% CI pound sterling 186m to pound sterling 235m) when a protease inhibitor was included. Compared with 1996 population-based cost estimates, the estimates for monotherapy decreased by 14%, by 11% for dual therapy, by 10% for triple therapy which included a NNRTI and by 9% if a protease inhibitor was used as part of a triple therapy regimen. Similarly, compared with 1996 estimates, the proportion of total costs attributable to treating asymptomatic individuals increased by 5% and 2-3% for people with symptomatic non-AIDS, while the proportion attributable for treating people with AIDS decreased by 8-9%.

State implementation of the AIDS drug assistance programs

Acquired immunodeficiency syndrome (AIDS) drug assistance programs (ADAPs) provide access to medications for people who lack other health coverage. In this article, the authors present the results of a 1997 survey identifying how 48 States implemented ADAPs, focusing on the number of beneficiaries, medical and financial eligibility criteria, the administration of waiting lists, and the coverage of drugs including protease inhibitors. Increased funding for ADAPs is necessary to maintain this important part of the public sector safety net for human immunodeficiency virus (HIV) care.

Modeling the long-term outcomes and costs of HIV antiretroviral therapy using HIV RNA levels: application to a clinical trial

A model was developed to gain insight into the potential clinical and economic impact of antiretroviral therapy for HIV-infected patients. Observed HIV RNA levels and CD4 cell counts are used in the model to estimate the probability that an individual progresses from asymptomatic infection to the first AIDS-defining illness and death and to estimate the total net cost of care and long-term cost-effectiveness of antiretroviral therapy. The model was applied to patients in a clinical trial (Merck protocol 035) that compared the surrogate marker response to triple therapy with indinavir (IDV; 800 mg every 8 hr) plus zidovudine (ZDV; 200 mg every 8 hr) plus lamivudine (3TC; 150 mg twice a day) to double therapy with ZDV+3TC. The model projected that for an individual without AIDS who received triple therapy the progression to AIDS and death would be delayed more than for a patient who received double therapy with ZDV+3TC if no other treatment options were offered. Because of this delay in disease progression, the total discounted cost over the initial 5-year period was projected to be $5100 lower for patients who received triple therapy compared with double therapy if suppression with triple therapy lasts up to 3 years. If suppression with triple therapy lasts up to 5 years, costs were projected to be higher with the triple combination, but 81% of the cost is offset by lower disease costs as a result of fewer patients progressing to AIDS. Over 20 years, total discounted cost was projected to be higher for the triple-therapy regimen primarily because of a longer estimated survival time. At 20 years, the incremental cost per life-year gained by adding IDV to a ZDV+3TC regimen was estimated at $13,229, which is well within the range of other widely accepted medical interventions.

Economic impact of delaying or preventing AIDS in persons with HIV

OBJECTIVES

To investigate how preventing or delaying the development of acquired immune deficiency syndrome (AIDS) [or other severe conditions related to the human immunodeficiency virus (HIV)] through antiretroviral therapy affects the lifetime cost of HIV/AIDS care, and to compare the cost of therapy with the potential savings in HIV/AIDS-related end-of-life care.

METHODS

The analysis utilized a previously developed economic model of HIV/AIDS-related medical care costs under various disease progression scenarios to compare the costs and benefits of antiretroviral therapy.

RESULTS

The analysis suggests that: (1) recent projections of long-term medical care cost savings due to highly effective protease inhibitor combination therapies are probably illusory; (2) it makes relatively little difference to the overall long-term cost of HIV/AIDS care whether combination antiretroviral therapy completely prevents or just substantially delays progression to AIDS; and (3) although combination therapy is not likely to save economic resources in the long run, it nevertheless can be highly cost effective.

CONCLUSIONS

The health-related benefits of antiretroviral therapy are not free, but appear to be worth the cost.