Cost effectiveness of combination HIV therapy: 3 years later

MAGIC Study: Aims, Design and Methods using SystemCHANGE™ to Improve Immunosuppressive Medication Adherence in Adult Kidney Transplant Recipients

BACKGROUND

Among adult kidney transplant recipients, non-adherence to immunosuppressive medications is the leading predictor of poor outcomes, including rejection, kidney loss, and death. An alarming one-third of kidney transplant patients experience medication non-adherence even though the problem is preventable. Existing adherence interventions have proven marginally effective for those with acute and chronic illnesses and ineffective for adult kidney transplant recipients. Our purpose is to describe the design and methods of the MAGIC (Medication Adherence Given Individual SystemCHANGE™) trial

METHODS/DESIGN

We report the design of a randomized controlled trial with an attention-control group to test an innovative 6-month SystemCHANGE™ intervention designed to enhance immunosuppressive medication adherence in adult non-adherent kidney transplant recipients from two transplant centers. Grounded in the Socio-Ecological Model, SystemCHANGE™ seeks to systematically improve medication adherence behaviors by identifying and shaping routines, involving supportive others in routines, and using medication taking feedback through small patient-led experiments to change and maintain behavior. After a 3-month screening phase of 190 eligible adult kidney transplant recipients, those who are <85 % adherent as measured by electronic monitoring, will be randomized into a 6-month SystemCHANGE™ intervention or attention-control phase, followed by a 6-month maintenance phase without intervention or attention. Differences in adherence between the two groups will be assessed at baseline, 6 months (intervention phase) and 12 months (maintenance phase). Adherence mediators (social support, systems-thinking) and moderators (ethnicity, perceived health) are examined. Patient outcomes (creatinine/blood urea nitrogen, infection, acute/chronic rejection, graft loss, death) and cost effectiveness are to be examined.

DISCUSSION

Based on the large effect size of 1.4 found in our pilot study, intervention shows great promise for increasing adherence. Grounded in the socio-ecological model, SystemCHANGE™ seeks to systematically improve medication adherence behaviors by identifying and shaping routines, involving supportive others in routines, and using medication taking feedback through small patient-lead experiments to change and maintain behavior. Medication adherence will be measured by electronic monitoring. Medication adherence persistence will be examined by evaluating differences between the two groups at the end of the 6-and 12- month phases. Mediators and moderators of medication adherence will be examined. Patient outcomes will be compared and a cost-effectiveness analysis will be conducted.

TRIAL REGISTRATION

ClinicalTrials.gov Registry: NCT02416479 Registered April 3, 2015.

The niche reduction approach: an opportunity for optimal control of infectious diseases in low-income countries?

BACKGROUND

During the last century, WHO led public health interventions that resulted in spectacular achievements such as the worldwide eradication of smallpox and the elimination of malaria from the Western world. However, besides major successes achieved worldwide in infectious diseases control, most elimination/control programs remain frustrating in many tropical countries where specific biological and socio-economical features prevented implementation of disease control over broad spatial and temporal scales. Emblematic examples include malaria, yellow fever, measles and HIV. There is consequently an urgent need to develop affordable and sustainable disease control strategies that can target the core of infectious diseases transmission in highly endemic areas.

DISCUSSION

Meanwhile, although most pathogens appear so difficult to eradicate, it is surprising to realize that human activities are major drivers of the current high rate of extinction among upper organisms through alteration of their ecology and evolution, i.e., their "niche". During the last decades, the accumulation of ecological and evolutionary studies focused on infectious diseases has shown that the niche of a pathogen holds more dimensions than just the immune system targeted by vaccination and treatment. Indeed, it is situated at various intra- and inter- host levels involved on very different spatial and temporal scales. After developing a precise definition of the niche of a pathogen, we detail how major advances in the field of ecology and evolutionary biology of infectious diseases can enlighten the planning and implementation of infectious diseases control in tropical countries with challenging economic constraints.

SUMMARY

We develop how the approach could translate into applied cases, explore its expected benefits and constraints, and we conclude on the necessity of such approach for pathogen control in low-income countries.

The Direct Medical Costs of Late Presentation (<350/mm) of HIV Infection over a 15-Year Period

We describe the immediate- and longer-term direct medical costs of care for individuals diagnosed with HIV at CD4 counts <350/mm(3) ("late presenters"). We collected and stratified by initial CD4 count all inpatient, outpatient, and drug costs for all newly diagnosed patients accessing HIV care within Southern Alberta from 1/1/1995 to 1/1/2010. 59% of new patients were late presenters. We found significantly higher costs for late presenters, especially inpatient costs, during the first year after accessing care. Direct medical costs remained almost twice as high for late presenters in subsequent years compared to patients presenting with CD4 counts >350/mm(3) despite significantly their improved CD4 counts. The sustained high cost for late presenters has implications for recent recommendations for wider routine HIV testing and the earlier initiation of cART. Earlier diagnosis and treatment, while increasing the immediate expenditures within a population, may produce both direct and indirect cost savings in the longer term.

Access to antiretroviral therapy among HIV/AIDS patients in khon kaen province, Thailand

This study attempted to identify the factors associated with the access to antiretroviral therapy (ARV) among HIV/AIDS patients in Khon Kaen Province, Thailand. We collected medical and sociodemographic data from the medical charts of adult patients living in the province who received medical services at two public hospitals in the province. The study period was from December 1, 2001 to February 28, 2002. Total 593 outpatients were included in the analysis. One hundred and forty-six patients (24.6%) received ARV. A logistic regression analysis was conducted to identify the factors associated with the use of ARV. Patients who were covered by the Civil Servant Medical Benefit Scheme were significantly more likely to receive ARV than those who were covered by the Universal Coverage Scheme (UC), a publicly-funded medical insurance (OR = 12.43; 95% CI = 6.03-25.62). The results of this study indicated that there were inequalities in access to and use of ARV among HIV/AIDS patients by health insurance status. The current government announced that they would include ARV in the benefits package of UC. It would be important to monitor how this policy will improve the access to ARV among HIV/AIDS patients.

When to Initiate Highly Active Antiretroviral Therapy in Low-Resource Settings: The Moroccan Experience

Background

The aim of this study was to assess the cost-effectiveness of HIV treatment alternatives – with and without highly active antiretroviral therapy (HAART) – within alternative strata based on the CD4+ T-cell count at the initiation of treatment in a low-resource setting.

Methods

A retrospective observational study was conducted following 286 HIV-positive individuals admitted to the principal teaching hospital in Casablanca, Morocco, between 1995 and 2002. Patients were stratified by CD4+ T-cell count and regression models were fitted to determine risk of opportunistic infection. Data on healthcare resource use were derived from patient records and were evaluated from the hospital perspective.

Results

HAART led to a significant reduction in the number of HIV-related opportunistic infections ( P<0.0001), extended survival (61.3 versus 55.2 months; P<0.0001) and reduced hospital stays ( P<0.0001) in comparison with care in the absence of HAART. When medical care and drug costs were considered together, HAART was more costly than providing treatment for opportunistic infections. The incremental cost-effectiveness ratio was lower than gross domestic product (GDP) per capita for patients starting HAART with a CD4+ T-cell count <200 cells/mm3, but this increased to nearly three times GDP per capita when HAART was initiated at CD4+ T-cell counts above this threshold.

Conclusions

HAART is more cost-effective than treating HIV-related opportunistic infections and, contrary to conclusions drawn in developed countries, HAART is more cost-effective when the CD4+ T-cell count drops to <200 cells/mm3.

Cost-effectiveness analysis of guidelines for antihypertensive care in Finland

BACKGROUND

Hypertension is one of the major causes of disease burden affecting the Finnish population. Over the last decade, evidence-based care has emerged to complement other approaches to antihypertensive care, often without health economic assessment of its costs and effects. This study looks at the extent to which changes proposed by the 2002 Finnish evidence-based Current Care Guidelines concerning the prevention, diagnosis, and treatment of hypertension (the ACCG scenario) can be considered cost-effective when compared to modelled prior clinical practice (the PCP scenario).

METHODS

A decision analytic model compares the ACCG and PCP scenarios using information synthesised from a set of national registers covering prescription drug reimbursements, morbidity, and mortality with data from two national surveys concerning health and functional capacity. Statistical methods are used to estimate model parameters from Finnish data. We model the potential impact of the different treatment strategies under the ACCG and PCP scenarios, such as lifestyle counselling and drug therapy, for subgroups stratified by age, gender, and blood pressure. The model provides estimates of the differences in major health-related outcomes in the form of life-years and costs as calculated from a 'public health care system' perspective. Cost-effectiveness analysis results are presented for subgroups and for the target population as a whole.

RESULTS

The impact of the use of the ACCG scenario in subgroups (aged 40-80) without concomitant cardiovascular and related diseases is mainly positive. Generally, costs and life-years decrease in unison in the lowest blood pressure group, while in the highest blood pressure group costs and life-years increase together and in the other groups the ACCG scenario is less expensive and produces more life-years. When the costs and effects for subgroups are combined using standard decision analytic aggregation methods, the ACCG scenario is cost-saving and more effective.

CONCLUSION

The ACCG scenario is likely to reduce costs and increase life-years compared to the PCP scenario in many subgroups. If the estimated trade-offs between the subgroups in terms of outcomes and costs are acceptable to decision-makers, then widespread implementation of the ACCG scenario is expected to reduce overall costs and be accompanied by positive outcomes overall.

The effectiveness of HIV partner counseling and referral services in increasing identification of HIV-positive individuals a systematic review

Partner counseling and referral services (PCRS) are part of the spectrum of care for HIV-positive people and their sexual or needle-sharing partners. Referral includes notifying partners of exposure, after which they are (ideally) tested and receive prevention or risk reduction counseling or enter into care (if they test positive). Using The Guide to Community Preventive Services's methods for systematic reviews, the effectiveness of PCRS was evaluated, including partner notification, in identifying a population at high risk of HIV infection and in increasing testing in those populations. In this review, PCRS efforts using provider referral were found to be effective in reaching a population with a high prevalence of HIV. Nine studies qualified for the review. In these studies, a range of one to eight partners was identified per index case (a person newly diagnosed with HIV who has partners who should be notified); a mean of 67% of identified partners were found and notified of their potential exposure to HIV, and a mean of 63% of those notified were tested (previously known "positives" were not tested). Of those tested, a mean of 20% were HIV positive. Therefore, even given that not all partners could be found and notified and that some who could be found did not accept testing, 1% to 8% of people named as potentially exposed and not previously known to be HIV positive were identified as HIV positive through partner notification (although these people were not necessarily infected by the index case). Evidence was insufficient to determine whether PCRS, including partner notification, was also effective in changing behavior or reducing transmission because available studies did not generally report on these outcomes. Little empirical evidence was available to assess potential harm of the interventions, but current studies have not shown substantial harms. Based on Community Guide rules of evidence, sufficient evidence shows that PCRS with partner notification by a public health professional ("provider referral") effectively increases identification of a high-prevalence target population for HIV testing.

Ten years of highly active antiretroviral therapy for HIV infection

Over the past 10 years, the management of HIV infection has been transformed by an increased number of effective antiretrovirals (ARVs), with more convenient dosing and improved tolerability. Optimal management of HIV infection includes at least three effective ARVs; from at least two different drug classes. Current strategies and drugs can effectively control HIV and significantly reduce morbidity and mortality. However, no cure is yet possible. Appropriate use of ARVs leads to suppression of virological replication (to below the limit of detection using commercial assays to measure HIV in plasma) and an increase in CD4(+) T cells with few adverse effects. Greater than 95% adherence to drug therapy is required for effective viral suppression and immunological improvement. Monotherapy, two-drug combinations, sequential ARVs, drug "cycling", and treatment interruptions are ineffective management strategies and lead to earlier disease progression and emergence of drug resistance. Drug-drug interactions are common and caution is required when prescribing ARVs that inhibit or induce the cytochrome P450 pathway.

Cost to achieve an undetectable viral load using recommended antiretroviral regimens

PURPOSE

The April 2005 Guidelines for the Use of Antiretroviral Agents in HIV-Infected Adults and Adolescents recommended 9 regimens to be combined with 2 nucleoside reverse transcriptase inhibitors (NRTIs). These regimens are effective in lowering viral load but are expensive. This study aimed to determine the cost for each regimen to achieve an undetectable viral load.

METHOD

52 clinical trials were reviewed. The outcome measure was cost per undetectable patient, C/PU, where C = cost of a drug, and PU = percent of patients with undetectable viral loads.

RESULTS

For 30 weeks, cost per undetectable (<400 copies/mL) ranged from 4,416 dollars (efavirenz) to 23,110 dollars (nelfinavir); for 42 weeks, the range was 5,729 dollars (efavirenz) to 24,071 dollars (indinavir/ritonavir); for 60 weeks, it ranged from 9,535 dollars (efavirenz) to 26,829 dollars (fosamprenavir); and for 84 weeks, it ranged from 12,203 dollars (efavirenz) to 22,960 dollars (nelfinavir). For <50 copies/mL, at 30 weeks the range was from 7,140 dollars (efavirenz) to 17,548 dollars (atazanavir); for 42 weeks, it ranged from 9,849 dollars (lopinavir/ritonavir) to 13,181 dollars (nelfinavir); for 60 weeks, it ranged from 8,702 dollars (nevirapine) to 36,034 dollars (atazanavir); and for 84 weeks, it ranged from 15,660 dollars (efavirenz) to 29,177 dollars (indinavir/ritonavir).

CONCLUSION

Efavirenz's low price and high effectiveness make it the least expensive means of achieving an undetectable viral load.

Cost-Effectiveness of an Intervention to Improve Adherence to Antiretroviral Therapy in HIV-Infected Patients

Adherence to antiretroviral medications has been shown to be an important factor in predicting viral suppression and clinical outcomes. The objective of this analysis was to assess the cost-effectiveness of a nursing intervention on antiretroviral adherence using data from a randomized controlled clinical trial as input to a computer-based simulation model of HIV disease. For a cohort of HIV-infected patients similar to those in the clinical trial (mean initial CD4 count of 319 cells/mm), implementing the nursing intervention in addition to standard care yielded a 63% increase in virologic suppression at 48 weeks. This produced increases in expected survival (from 94.5 to 100.9 quality-adjusted life months) and estimated discounted direct lifetime medical costs ($253,800 to $261,300). The incremental cost-effectiveness ratio for the intervention was $14,100 per quality-adjusted life year gained compared with standard care. Adherence interventions with modest effectiveness are likely to provide long-term survival benefit to patients and to be cost-effective compared with other uses of HIV care funds.

Distribution of health care expenditures for HIV-infected patients

BACKGROUND

Health care expenditures for persons infected with human immunodeficiency virus (HIV) in the United State determined on the basis of actual health care use have not been reported in the era of highly active antiretroviral therapy.

METHODS

Patients receiving primary care at the University of Alabama at Birmingham HIV clinic were included in the study. All encounters (except emergency room visits) that occurred within the University of Alabama at Birmingham Hospital System from 1 March 2000 to 1 March 2001 were analyzed. Medication expenditures were determined on the basis of 2001 average wholesale price. Hospitalization expenditures were determined on the basis of 2001 Medicare diagnostic related group reimbursement rates. Clinic expenditures were determined on the basis of 2001 Medicare current procedural terminology reimbursement rates.

RESULTS

Among the 635 patients, total annual expenditures for patients with CD4+ cell counts <50 cells/microL (36,533 dollars per patient) were 2.6-times greater than total annual expenditures for patients with CD4+ cell counts > or =350 cells/microL (13,885 dollars per patient), primarily because of increased expenditures for nonantiretroviral medication and hospitalization. Expenditures for highly active antiretroviral therapy were relatively constant at approximately 10,500 dollars per patient per year across CD4+ cell count strata. Outpatient expenditures were 1558 dollars per patient per year; however, the clinic and physician component of these expenditures represented only 359 dollars per patient per year, or 2% of annual expenses. Health care expenditures for patients with HIV infection increased substantially for those with more-advanced disease and were driven predominantly by medication costs (which accounted for 71%-84% of annual expenses).

CONCLUSIONS

Physician reimbursements, even with 100% billing and collections, are inadequate to support the activities of most clinics providing HIV care. These findings have important implications for the continued support of HIV treatment programs in the United States.

Cost-effectiveness of highly active antiretroviral therapy in South Africa

BACKGROUND

Little information exists on the impact of highly active antiretroviral therapy (HAART) on health-care provision in South Africa despite increasing scale-up of access to HAART and gradual reduction in HAART prices.

METHODS AND FINDINGS

Use and cost of services for 265 HIV-infected adults without AIDS (World Health Organization [WHO] stage 1, 2, or 3) and 27 with AIDS (WHO stage 4) receiving HAART between 1995 and 2000 in Cape Town were compared with HIV-infected controls matched for baseline WHO stage, CD4 count, age, and socioeconomic status, who did not receive antiretroviral therapy (ART; No-ART group). Costs of service provision (January 2004 prices, USD 1 = 7.6 Rand) included local unit costs, and two scenarios for HAART prices for WHO recommended first-line regimens: scenario 1 used current South African public-sector ART drug prices of $730 per patient-year (PPY), whereas scenario 2 was based on the anticipated public-sector price for locally manufactured drug of $181 PPY. All analyses are presented in terms of patients without AIDS and patients with AIDS. For patients without AIDS, the mean number of inpatient days PPY was 1.08 (95% confidence interval [CI]: 0.97-1.19) for the HAART group versus 3.73 (95% CI: 3.55-3.97) for the No-ART group, and 8.71 (95% CI: 8.40-9.03) versus 4.35 (95% CI: 4.12-5.61), respectively, for mean number of outpatient visits PPY. Average service provision PPY was $950 for the No-ART group versus $1,342 and $793 PPY for the HAART group for scenario 1 and 2, respectively, whereas the incremental cost per life-year gained (LYG) was $1,622 for scenario 1 and $675 for scenario 2. For patients with AIDS, mean inpatients days PPY was 2.04 (95% CI: 1.63-2.52) for the HAART versus 15.36 (95% CI: 13.97-16.85) for the No-ART group. Mean outpatient visits PPY was 7.62 (95% CI: 6.81-8.49) compared with 6.60 (95% CI: 5.69-7.62) respectively. Average service provision PPY was $3,520 for the No-ART group versus $1,513 and $964 for the HAART group for scenario 1 and 2, respectively, whereas the incremental cost per LYG was cost saving for both scenarios. In a sensitivity analysis based on the lower (25%) and upper (75%) interquartile range survival percentiles, the incremental cost per LYG ranged from $1,557 to $1,772 for the group without AIDS and from cost saving to $111 for patients with AIDS.

CONCLUSION

HAART is a cost-effective intervention in South Africa, and cost saving when HAART prices are further reduced. Our estimates, however, were based on direct costs, and as such the actual cost saving might have been underestimated if indirect costs were also included.

Economic models of antiretroviral therapy: searching for the optimal strategy

The diffusion of protease inhibitors and non-nucleoside reverse transcriptase inhibitors in the US in 1996 and 1997 reduced the number of deaths attributable to HIV disease and changed the way we think about the illness. Today, HIV disease may be deemed a fairly expensive chronic condition rather than an intolerably expensive fatal illness. Although most studies have found that patients receiving new drug therapies are hospitalised less frequently than patients who received early drug therapies, it is unclear whether the diffusion of new drug therapies has increased or decreased the annual cost of care. However, it is evident that the diffusion of new drug therapies has increased the lifetime cost of care. Analysts rely on models to simulate the course and cost of HIV disease. This study reviews the evolution of these models, paying particular attention to how these models estimate the cost of care. The primary findings of this review are that the economic data used in these models are often too imprecise to accurately identify the cost of each disease stage and are almost always outdated. Moreover, it was found that estimates of drug costs in these models may not accurately reflect actual expenditures.

Cost-effectiveness of enfuvirtide in treatment-experienced patients with advanced HIV disease

OBJECTIVE

Enfuvirtide (ENF) has been shown to improve short-term virologic responses when given to highly treatment-experienced patients with advanced HIV disease. Because of the high cost of ENF compared with other antiretroviral agents, our objectives were to determine the potential long-term clinical impact and cost-effectiveness of ENF in these patients.

METHODS

We used a computer simulation model of HIV disease to project life expectancy, quality-adjusted life expectancy, cost, and cost-effectiveness of ENF in treatment-experienced patients. Input data were from the T-20 versus Optimized Regimen Only (TORO) 1 and 2 trials, 2 studies comparing ENF plus an optimized background regimen (OBR) with an OBR alone.

RESULTS

ENF plus an OBR increased projected discounted quality-adjusted life expectancy from 45.4 months with an OBR alone to 54.9 months, a difference of 9.5 quality-adjusted life-months. At the current annual ENF cost of US 18,500 dollars per year (in 2001 US dollars), the incremental cost-effectiveness ratio for ENF plus an OBR was US 69,500 dollars per quality-adjusted life-year (QALY) compared with an OBR alone. When 48-week virologic suppression rates for ENF plus an OBR were varied from a 50% reduction to a 250% increase in the suppression rate attributable to ENF, gains in quality-adjusted life expectancy ranged from 4.5 to 25.9 quality-adjusted life-months compared with an OBR alone, with cost-effectiveness ratios ranging from US 97,900 dollars per QALY to US 52,300 dollars per QALY gained. If ENF is continued after the HIV RNA level returns to the pretreatment baseline, the cost-effectiveness ratio increases to US 168,200 dollars per QALY.

CONCLUSIONS

In highly treatment-experienced patients, ENF plus an OBR provides substantial gains in quality-adjusted life expectancy compared with an OBR alone. Although ENF plus an OBR is less cost-effective than other commonly used interventions in HIV disease, its use may be justified, given the poor prognosis of these patients and their otherwise limited options for antiretroviral therapy.

Impact of highly active antiretroviral therapy on CD4+ T cells and viral load of children with AIDS: a population-based study

In this study, we sought to characterize the changes over time at the population level on CD4(+) T cells and plasma viral load (VL) levels of HIV-1-infected children with or without AIDS. We carried out a retrospective study in 114 HIV-infected children during the calendar period that a highly active antiretroviral therapy (HAART) protocol was used. The HAART protocol consisted of three drugs: nucleoside analogue HIV-1 reverse transcriptase inhibitors, and/or HIV protease inhibitors, and/or nonnucleoside analogue HIV-1 reverse transcriptase inhibitors. The mean of CD4(+) T cells percentage and log(10) VL per calendar year were stratified by AIDS diagnostic. As new HAART strategies become available, an increase of CD4(+) T cells and a decrease of VL were observed over time, in children with and without AIDS. In 2001, children with AIDS reached values of CD4(+) T cells and VL similar to children without AIDS. In conclusion, our study shows that the generalized use of HAART has permitted improvement in immunological and virological status of HIV-infected children without AIDS, and more importantly in children with AIDS.

Association between diarrhea and quality of life in HIV-infected patients receiving highly active antiretroviral therapy

Diarrhea is a common symptom that many HIV patients experience either as a consequence of HIV infection or of highly active antiretroviral therapy (HAART). A multicenter, prospective observational study was conducted in 11 AIDS clinics in Italy to determine the effect of diarrhea on health-related quality of life among patients receiving HAART. The study enrolled 100 consecutive HIV positive patients who had diarrhea while on HAART. For each enrolled patient a control patient with matching disease stage who did not have diarrhea was identified using existing data from another prospective observational study conducted in 34 AIDS clinics (including the 11 in current study). Quality of life was measured by MOS-HIV Health Survey (MOS-HIV). Paired t-test and multiple regression analysis were used to compare the quality of life among patients with and without diarrhea. Mean patient age was 40 +/- 7 years; 69% were male. Mean CD4 cell count was 342 +/- 239 cells/mm3; 59% had AIDS. Of the cases, 49 patients had severe diarrhea (> 5 bowel movements or > 3 watery per day) and 46 patients had moderate diarrhea (3-5 bowel movements). Compared to matched control patients, cases experiencing diarrhea while on HAART had significantly lower MOS-HIV scores in all domains. The significant adverse effect of diarrhea on quality of life should be considered when choosing the appropriate antiretroviral drugs regimen.

Synthesis of 2,4-Diamino-6-[2‘-O-(ω-carboxyalkyl)oxydibenz[b,f]azepin-5-yl]methylpteridines as Potent and Selective Inhibitors of Pneumocystis carinii, Toxoplasma gondii, and Mycobacterium avium Dihydrofolate Reductase

Six previously undescribed N-(2,4-diaminopteridin-6-yl)methyldibenz[b,f]azepines with water-solubilizing O-carboxyalkyloxy or O-carboxybenzyloxy side chains at the 2'-position were synthesized and compared with trimethoprim (TMP) and piritrexim (PTX) as inhibitors of dihydrofolate reductase (DHFR) from Pneumocystis carinii (Pc), Toxoplasma gondii (Tg), and Mycobacterium avium (Ma), three of the opportunistic organisms known to cause significant morbidity and mortality in patients with AIDS and other disorders of the immune system. The ability of the new analogues to inhibit reduction of dihydrofolate to tetrahydrofolate by Pc, Tg, Ma, and rat DHFR was determined, and the selectivity index (SI) was calculated from the ratio IC(50)(rat DHFR)/IC(50)(Pc, Tg, or Ma DHFR). The IC(50) values of the 2'-O-carboxypropyl analogue (10), with SI values in parentheses, were 1.1 nM (1300) against Pc DHFR, 9.9 nM (120) against Tg DHFR, and 2.0 nM (600) against Ma DHFR. The corresponding values for the 2'-O-(4-carboxybenzyloxy) analogue (12) were 1.0 nM (560), 22 nM (21), and 0.75 nM (630). By comparison, the IC(50) and SI values for TMP were Pc, 13 000 nM (14); Tg, 2800 nM (65); and Ma, 300 nM (610). For the prototypical potent but nonselective inhibitors PTX and TMX, respectively, these values were Pc, 13 nM (0.26) and 47 nM (0.17); Tg, 4.3 nM (0.76) and 16 nM (0.50); Ma, 0.61 nM (5.4) and 1.5 nM (5.3). Thus 10 and 12 met the criterion for DHFR inhibitors that combine the high selectivity of TMP with the high potency of PTX and TMX.

The relationship between prevention of mother to child transmission of HIV and stakeholder decision making in Uganda: implications for health policy

OBJECTIVES

To explore a selection of stakeholders' use of evidence and other reasons in the relative ranking of the prevention of mother to child HIV transmission with nevirapine in a setting of extreme resource scarcity.

DESIGN

Group interviews using nominal group technique with provision of evidence.

SETTING

One rural and one urban district in Uganda.

PARTICIPANTS

People living with HIV/AIDS, people from the general population, planners, health workers and people with hypertension.

MAIN OUTCOME MEASURE

relative ranking of prevention of vertical HIV transmission with nevirapine compared to nine other interventions for different conditions and evaluation of participants' use of evidence in the ranking.

RESULTS

In the overall final ranking, prevention of vertical HIV transmission with nevirapine was ranked as number five compared to the other eight conditions. Treatment for childhood diseases and highly active anti retroviral treatment (HAART) for HIV/AIDS were ranked higher. Group specific ranking followed the same pattern, although the people living with HIV-group ranked HAART consistently as number one.

CONCLUSIONS

Stakeholders seem to rank prevention of vertical HIV transmission lower than treatment for malaria, pneumonia and diarrhoea. Policies considering prevention of vertical transmission of HIV should consider its implications. This study shows that stakeholders are open to considering evidence in assessing the relative priority of different interventions competing for scarce resources. More research is needed to develop methods that can involve representative stakeholders, including the public, in good and legitimate decisions on priorities.

A multicentre study of patient survival, disability, quality of life and cost of care: among patients with AIDS in northern Italy

OBJECTIVE

To describe the epidemiological, clinical and economic changes that occurred in the HIV epidemic in Italy prior to and after the introduction of highly active antiretroviral therapy (HAART).

DESIGN

A prospective, observational, multicentre case-control study was conducted comparing data, collected over 6 months, from an AIDS cohort in 1998 with that of a cohort in 1994. Out of 77 patients with AIDS in the 1998 cohort, 74 survived. These 74 patients were matched for severity of illness with 74 patient survivors from the 1994 cohort to enable valid comparisons of mortality, disability-dependency (DD), health-related QOL (HR-QOL), and direct costs.

RESULTS

Overall, a considerable difference was observed in mortality (33.8% in 1994 vs 3.9% in 1998) between unmatched patients of the two cohorts. As for matched patients, the number of hospital admissions was 1.7 in 1994 and 0.8 in 1998; the average length of stay was 28.1 days in 1994 and 12.6 days in 1998. The direct cost per patient per year was euro15 390 and euro11 465 for the 1994 and 1998 cohorts, respectively (1999 values). The 1998 patient cohort had significantly better HR-QOL at 6 months in two domains of the instrument used (emotional reaction and energy) and the percentage of totally dependent patients was significantly lower compared with the 1994 cohort (1.4% vs 6.8%).

CONCLUSIONS

This is the first study to present a comprehensive comparison of direct costs, DD and HR-QOL of patients with AIDS between two time periods. The use of a case-control design has enabled changes in costs and outcomes to be linked to the introduction of HAART in Italy in 1997.

Cost Effectiveness Analysis of Routine Use of Genotypic Antiretroviral Resistance Testing after Failure of Antiretroviral Treatment for HIV

Objectives

Single use of genotypic antiretroviral resistance testing (GART) after first failure of highly active antiretroviral therapy (HAART) was reported to be cost effective; its use prior HAART initiation is unknown. Guidelines recommend GART after each treatment failure. We assessed the cost effectiveness of GART used routinely after first and subsequent treatment failures. Furthermore, we determined the minimum effectiveness required for GART prior to the first HAART to be as cost effective as after treatment failure.

Design and methods

We developed a decision-analytic Markov model to estimate lifetime clinical and economic outcomes in a cohort of HIV patients starting HAART. Rates of treatment failure, estimates of GART effectiveness and data on disease progression were derived from published trials and observational studies. A cost effectiveness analysis was performed from the perspective of the healthcare system using cost data from a Central European healthcare setting. Deterministic and probabilistic sensitivity analyses using Monte Carlo technique were performed.

Results

GART after treatment failures increased life expectancy by 9 months and undiscounted life-time costs per case by €16406. The discounted incremental cost effectiveness ratio was €22510 per life-year gained (€/LY). Best- and worst-case scenarios yielded 16 512 €/LY and 42900 €/LY, respectively. GART prior to the initiation of HAART would be equally cost effective if it could reduce the probability of first HAART failure by at least 36%.

Conclusion

Routine use of GART after treatment failures is cost effective. GART prior to the first HAART would be equally cost effective if it could lower the probability of first HAART failure by approximately a third.

HIV infection and advanced age emerging epidemiological, clinical, and management issues

While the mean age of HIV/AIDS patients at first diagnosis is progressively rising, no updated epidemiological estimates, controlled clinical data, and randomized therapeutic trials, are available regarding clinical and laboratory response to antiretroviral therapy, safety of anti-HIV compounds and their associations, potential drug-drug interactions, short- and long-term toxicity, consequences on underlying disorders, or interactions with concomitant pharmacological regimens, in the elderly. The life expectancy of HIV-infected persons treated with highly active antiretroviral therapy (HAART) now approximates that of general population matched for age, while also AIDS definition itself has lost most of its epidemiological and clinical significance, thanks to the immunoreconstitution resulting from the large-scale use of potent HAART regimens. The increased survival of HIV-infected patients, the late recognition of other subjects with missed or delayed diagnosis are responsible for a further expected rise of mean age of HIV-infected individuals, so that the patient population aged 60-70 years or more is expected to increase in coming years. Unfortunately, the majority of therapeutic trials involving antiretroviral therapy, as well as antimicrobial chemoprophylaxis for AIDS-related opportunistic complications, have advanced age and/or concurrent end-organ disorders among main exclusion criteria, or the design of these studies does not allow to extrapolate data regarding older patients, compared with younger ones. The very limited data presently available seem to demonstrate that HAART has a virological efficacy in the elderly comparable with that of younger adults, but immunological recovery is often slower and blunted, although several studies clearly demonstrated that thymic function is preserved until late adult age. When facing an HIV-infected patient with advanced age, health care givers have to pay careful attention to eventual end-organ disorders, all possible pharmacological interactions, overlapping toxicity due to concurrent drug administration. All these issues may significantly interfere with HAART activity, patient's adherence to prescribed medications, and frequency and severity of untoward effects. The guidelines of antiretroviral therapy and those of treatment and prophylaxis of AIDS-related diseases deserve appropriate updates, paralleling the increasing mean age of HIV-infected population. Moreover, epidemiological figures need an increased focus on older age, while clinical trials specifically targeting on the elderly population are mandatory to have reliable data on all aspects of HAART administration in advanced age.

Costs of medical services for patients with HIV/AIDS in Khon Kaen, Thailand

OBJECTIVE

To estimate the savings and cost of providing highly active antiretroviral therapy (HAART) to adult patients with AIDS under Universal Coverage (UC) in Khon Kaen Province, Thailand.

DESIGN

Micro-costing of outpatient and inpatient services of two referral hospitals, and cost modelling.

SETTING

Khon Kaen Regional Hospital and Northeast Regional Infectious Hospital.

PATIENTS

Adult patients who resided in Khon Kaen and made outpatient visits at and/or those who were discharged from those hospitals from 1 December 2001 to 28 February 2002.

MAIN OUTCOME MEASURE

The average cost per outpatient visit and per inpatient day. Based on these figures, the savings and cost of providing HAART to adult patients with AIDS under UC at outpatient settings in this province were estimated.

RESULTS

The average cost per outpatient visit with and without antiretroviral drugs (ARV) was US$294.2 and US$26.1, respectively. The average cost per inpatient day with and without ARV drugs was US$368.1 and US$43.8, respectively. The net annual cost of HAART was estimated to be US$5 674 629. This is equivalent to 20.0% of the annual UC budget for adults in this province in 2002. Sensitivity analysis and projection to the year 2006 were conducted.

CONCLUSION

A large increase in the budget would be required to provide HAART to all adult patients with AIDS under UC. However, the sensitivity analysis showed it would be an affordable policy option if low-cost antiretroviral drugs were successfully introduced. This type of analysis would be useful to assess the financial implications of providing HAART in public health systems worldwide.

Modifications of health resource-use in Italy after the introduction of highly active antiretroviral therapy (HAART) for human immunodeficiency virus (HIV) infection. Pharmaco-economic implications in a population-based setting

OBJECTIVE

To assess the impact of highly active antiretroviral therapy (HAART) on health resource utilisation (HRU) and to estimate associated direct costs in a population based setting.

DESIGN

Retrospective study of all patients in the Institute of Infectious and Tropical Diseases (Brescia, Northern Italy) during a 4 years period related to the prescription of HAART has been performed: from 1997 (before HAART) to 2000 (after substantial period of HAART prescription).

MAIN OUTCOME MEASURES AND RESULTS

HIV inpatient admissions (IA's) decreased from 506.8/1000 patients (pts) in 1997 to 246.3/1000 pts in the year 2000. Day care admissions (DCA's) also decreased from 1658.3/1000 pts to 942/1000 pts, while outpatient consultations (OC's) increased from 2046.9/1000 pts to 2590.6/1000 pts in the same years, respectively. By contrast, a relative increase of IA's and DCA's of patients whose serostatus was HIV-negative or unknown has been found. Cost of antiretroviral therapy increased by 2582 Euro (2272 US Dollars), while cost of HIV care (IA+DCA+OC) decreased by 1546 Euro (1360.4 US Dollars) per patient, resulting in a saving in direct cost equal to 60% of the increase in the expenditure for antiretroviral drugs.

CONCLUSIONS

Our results demonstrate the shift of HIV care from inpatient to outpatient services that occurred after HAART had been introduced into clinical practice. Despite persisting clinical benefits, an increase in total direct cost for HIV pts has been seen for the first time during the HAART era in the year 2000, probably due to an over-prescription of HAART, according to actual Guideline for antiretroviral therapy use, to pts who were not at risk of clinical progression in the short term. Pharmacoeconomical surveillance of HAART is necessary while a favourable impact on the saving in cost is expected from the new treatment guidelines that suggest a relative delay in starting HAART.

Total joint arthroplasty in human immunodeficiency virus-positive patients: an alarming rate of early failure

The results of 21 total joint arthroplasties (13 knees, 8 hips) in 15 patients were reviewed. There were 13 men and 2 women with an average age of 38 years (range, 28 to 69 years). The mean follow-up period was 10.2 years (range, 2 to 23 years). Six patients died within an average of 10.6 years (range, 3 to 18 years) of joint arthroplasty. All patients died of AIDS. Deep infection developed in 6 joints. Knee Society scores improved significantly, but 13 repeat surgeries were required. An alarmingly high rate of complications was found after total knee and total hip arthroplasty in these patients with human immunodeficiency virus (HIV). Physicians and surgeons should be made aware of this high rate of complications after joint arthroplasty in patients with HIV and include a frank discussion of this information with their patients who are contemplating total joint arthroplasty.

HIV disease and advanced age: an increasing therapeutic challenge

The mean age of patients at both first HIV detection and AIDS diagnosis is progressively rising over time. However, reliable epidemiological estimates, clinical data or controlled therapeutic and outcome figures are lacking for elderly patients, especially with regard to laboratory and clinical response to antiretroviral therapy, treatment tolerability, drug-drug interactions, short- and long-term toxicity, and interactions with underlying illnesses and concurrent pharmacological treatment. In fact, the large majority of randomised, controlled trials evaluating and comparing new antiretroviral drugs or anti-HIV therapeutic strategies, as well as antimicrobial treatment or chemoprophylaxis of HIV-related complications, either excluded patients with advanced age and/or concurrent disorders or did not offer substudies or detailed data analysis focusing on older patients compared with younger ones. The life expectancy of HIV-infected persons receiving highly active antiretroviral therapy (HAART) is now extended (approaching that of the general population), so that the definition of AIDS has lost its epidemiological and clinical significance thanks to the immune reconstitution resulting from potent antiretroviral therapy. However, an ever-increasing number of individuals aged > or =50 years with HIV infection is expected in the coming years, as a result of both increased survival of patients with treated disease and delayed recognition of individuals with occult HIV disease. The limited data available about combined antiretroviral therapy in the elderly seem to show an overlapping virological success rate but a slower and blunted immune recovery compared with younger patients. Thymic output, however, seems somewhat preserved even in adulthood and may contribute to the reconstitution of most of the quantitative and functional T cell abnormalities caused by HIV disease. More attention must be paid to underlying end-organ disorders, as well as expected pharmacological interactions and combined drug toxicity that may interfere with HAART efficacy and patients' compliance with recommended regimens and could lead to increased adverse effects. The available guidelines for antiretroviral treatment and therapy and prophylaxis of AIDS-related illnesses should be regularly updated and should include problems related to HIV disease in an aging population. Specific trials or substudies focusing on older people are warranted to obtain controlled data on all issues of antiretroviral therapy in the elderly, including time and mode of initiation, and modification and salvage HAART regimens. Antiretroviral drug dosage adjustment to take into account underlying pathological conditions or other pharmacological treatments is another emerging issue.

AIDS Drug Assistance Programs: highlighting inequities in human immunodeficiency virus-infection health care in the United States

The AIDS Drug Assistance Programs (ADAPs) were founded in 1987 to pay for human immunodeficiency virus (HIV)-related medications in the United States and to help provide prescriptions for HIV-infected patients ineligible for Medicaid who have no private health insurance. As HIV care has shifted from the inpatient to the outpatient arena and as patients live longer because of more-effective antiretroviral therapy, medication costs have increased, and ADAPs have increasingly been operating under emergency measures, with coverage limitations and eligibility restrictions. Because these programs operate at the state level, inequalities in resource distribution to those in need are manifest and appear to contribute to differences in disease outcomes that are based solely on patients' place of residence. Cost-effectiveness analysis would offer a more informed basis for distribution of ADAP resources in an efficient and equitable manner, leading to a standardized national structure.

State AIDS Drug Assistance Programs: equity and efficiency in an era of rapidly changing treatment standards

BACKGROUND

The 54 state AIDS Drug Assistance Programs (ADAP) provide medications to HIV-infected persons with limited resources. Eligibility and coverage vary, raising concerns about health inequities.

OBJECTIVE

To compare the relative clinical and economic performance of ADAP programs.

RESEARCH DESIGN

A state-transition simulation model of HIV disease was used to explore the clinical consequences and lifetime costs associated with selected state policies. Clinical data came from the Multicenter AIDS Cohort Study, AIDS Clinical Trials Group Protocol 320, and other published randomized trials. Cost data came from the national AIDS Cost and Services Utilization Survey, and the 1999 Red Book. ADAP data came from National Association of State and Territorial AIDS Directors reports and interviews.

MEASURES

Projected life expectancy, quality-adjusted life expectancy, total lifetime direct medical costs, cost-effectiveness in dollars per quality-adjusted life year (QALY) gained.

RESULTS

ADAPs vary considerably in terms of formulary policies, health outcomes, expected costs, and cost-efficiency. Conservative projections, based on a cohort with starting mean CD4 count of 250 cells/microL, yield life expectancies ranging from 5.36 to 6.81 life years (4.69-6.01 quality-adjusted life years [QALYs]). Total per person lifetime direct medical costs range from $81,200 to $112,700; higher costs reflect increased spending on medications. Expected costs per QALY gained range from $7000 to $28,000. Under pessimistic assumptions regarding initial CD4 counts, drug efficacy, and discounting, the most comprehensive policy remains below $33,000/QALY.

CONCLUSIONS

Even the most comprehensive ADAPs constitute a cost-effective use of HIV care resources. A uniform, national ADAP formulary warrants consideration.

Health and federal budgetary effects of increasing access to antiretroviral medications for HIV by expanding Medicaid

OBJECTIVES. This study modeled the health and federal fiscal effects of expanding Medicaid for HIV-infected people to improve access to highly active antiretroviral therapy.

METHODS

A disease state model of the US HIV epidemic, with and without Medicaid expansion, was used. Eligibility required a CD4 cell count less than 500/mm3 or viral load greater than 10,000, absent or inadequate medication insurance, and annual income less than $10,000. Two benefits were modeled, "full" and "limited" (medications, outpatient care). Federal spending for Medicaid, Medicare, AIDS Drug Assistance Program, Supplemental Security Income, and Social Security Disability Insurance were assessed.

RESULTS

An estimated 38,000 individuals would enroll in a Medicaid HIV expansion. Over 5 years, expansion would prevent an estimated 13,000 AIDS diagnoses and 2600 deaths and add 5,816 years of life. Net federal costs for all programs are $739 million (full benefits) and $480 million (limited benefits); for Medicaid alone, the costs are $1.43 and $1.17 billion, respectively. Results were sensitive to awareness of serostatus, highly active antiretroviral therapy cost, and participation rate. Strategies for federal cost neutrality include Medicaid HIV drug price reductions as low as 9% and private insurance buy-ins.

CONCLUSIONS

Expansion of the Medicaid eligibility to increase access to antiretroviral therapy would have substantial health benefits at affordable costs.

Are we headed for a resurgence of the HIV epidemic among men who have sex with men?

HIV remains a critical health issue for men who have sex with men (MSM). In the United States, an estimated 365,000 to 535,000 MSM are living with HIV, and 42% of new HIV infections occur in this population. Recent data on sexually transmitted diseases and on sexual behavior indicate the potential for a resurgence in HIV infections among MSM. Outbreaks of gonorrhea and syphilis have been reported in a growing number of cities, and several studies have observed an increase in unprotected anal intercourse among MSM. These increases in HIV risk behavior may be attributed to several factors that have affected the sexual practices of MSM, including changes in beliefs regarding the severity of HIV disease. These emerging data have implications for surveillance and intervention research activities and indicate a need to reevaluate, refocus, and reinvigorate HIV prevention efforts for MSM. Our recommendations for addressing the HIV prevention needs of MSM include the need to consider HIV-related issues within the broader context of the physical, mental, and sexual health of MSM.

HIV chemotherapy

The use of chemotherapy to suppress replication of the human immunodeficiency virus (HIV) has transformed the face of AIDS in the developed world. Pronounced reductions in illness and death have been achieved and healthcare utilization has diminished. HIV therapy has also provided many new insights into the pathogenesis and the viral and cellular dynamics of HIV infection. But challenges remain. Treatment does not suppress HIV replication in all patients, and the emergence of drug-resistant virus hinders subsequent treatment. Chronic therapy can also result in toxicity. These challenges prompt the search for new drugs and new therapeutic strategies to control chronic viral replication.

The cost effectiveness of combination antiretroviral therapy for HIV disease

BACKGROUND

Combination antiretroviral therapy with a combination of three or more drugs has become the standard of care for patients with human immunodeficiency virus (HIV) infection in the United States. We estimated the clinical benefits and cost effectiveness of three-drug antiretroviral regimens.

METHODS

We developed a mathematical simulation model of HIV disease, using the CD4 cell count and HIV RNA level as predictors of the progression of disease. Outcome measures included life expectancy, life expectancy adjusted for the quality of life, lifetime direct medical costs, and cost effectiveness in dollars per quality-adjusted year of life gained. Clinical data were derived from major clinical trials, including the AIDS Clinical Trials Group 320 Study. Data on costs were based on the national AIDS Cost and Services Utilization Survey, with drug costs obtained from the Red Book.

RESULTS

For patients similar to those in the AIDS Clinical Trials Group 320 Study (mean CD4 cell count, 87 per cubic millimeter), life expectancy adjusted for the quality of life increased from 1.53 to 2.91 years, and per-person lifetime costs increased from $45,460 to $77,300 with three-drug therapy as compared with no therapy. The incremental cost per quality-adjusted year of life gained, as compared with no therapy, was $23,000. On the basis of additional data from other major studies, the cost-effectiveness ratio for three-drug therapy ranged from $13,000 to $23,000 per quality-adjusted year of life gained. The initial CD4 cell count and drug costs were the most important determinants of costs, clinical benefits, and cost effectiveness.

CONCLUSIONS

Treatment of HIV infection with a combination of three antiretroviral drugs is a cost-effective use of resources.

Expenditures for the care of HIV-infected patients in the era of highly active antiretroviral therapy

BACKGROUND

The introduction of expensive but very effective antiviral medications has led to questions about the effects on the total use of resources for the care of patients with human immunodeficiency virus (HIV) infection. We examined expenditures for the care of HIV-infected patients since the introduction of highly active antiretroviral therapy.

METHODS

We interviewed a random sample of 2864 patients who were representative of all American adults receiving care for HIV infection in early 1996, and followed them for up to 36 months. We estimated the average expenditure per patient per month on the basis of self-reported information about care received.

RESULTS

The mean expenditure was $1,792 per patient per month at base line, but it declined to $1,359 for survivors in 1997, since the increases in pharmaceutical expenditures were smaller than the reductions in hospital costs. Use of highly active antiretroviral therapy was independently associated with a reduction in expenditures. After adjustments for the interview date, clinical status, and deaths, the estimated annual expenditure declined from $20,300 per patient in 1996 to $18,300 in 1998. Expenditures among subgroups of patients varied by a factor of as much as three. Pharmaceutical costs were lowest and hospital costs highest among underserved groups, including blacks, women, and patients without private insurance.

CONCLUSIONS

The total cost of care for adults with HIV infection has declined since the introduction of highly active antiretroviral therapy. Expenditures have increased for medications but have declined for other services. However, there are large variations in expenditures across subgroups of patients.

Highly active antiretroviral therapy: pharmacoeconomic issues in the management of HIV infection

The advent of highly active antiretroviral therapy (HAART), including protease inhibitors and/or non-nucleoside reverse transcriptase inhibitors, for the treatment of HIV infection has led to a dramatic decline of morbidity and mortality. The acquisition costs of HAART are substantial. However, these costs are partially offset by reduced inpatient care for opportunistic infections and other AIDS-related diseases. Furthermore, job productivity in patients infected with HIV is increased under HAART. In developed countries with a low unemployment rate, the discounted value of savings caused by increased productivity in earlier years exceeds the discounted value of later increases in costs resulting from morbidity. Therefore, HAART represents a very efficient treatment strategy that leads to overall cost savings when taking a societal perspective.