Economic evaluation of treatment administration strategies of ganciclovir for cytomegalovirus retinitis in HIV/AIDS patients in Thailand: a simulation study

Quantifying the Value of Introducing an Oral Drug Delivery Option for Edaravone: A Review of Analyses Evaluating the Economic Impact of Oral versus Intravenous Formulations

Background

Drug formulation and route of administration can have an impact on not only patients’ quality of life and disease outcomes but also costs of care. It is essential for decision makers to use appropriate economic modeling methods to guide drug coverage policies and to support patients’ decision-making.

Purpose

To illustrate key cost considerations for decision makers in economic evaluation of innovative oral formulations as alternatives to intravenous medication.

Materials and Methods

A structured literature review was conducted using the PubMed database to examine methods used for quantifying the economic impact of introducing a new oral pharmaceutical formulation as an alternative to intravenous medication. To illustrate the methods described in this review, a cost-minimization analysis was conducted to quantify the impact of introducing an oral formulation of a medication originally developed as an intravenous treatment for amyotrophic lateral sclerosis.

Results

We identified 14 published evaluations of oral and intravenous formulations from 10 countries across a variety of disease areas. The identified studies used cost-effectiveness (n=10), cost-minimization (n=2), and cost-calculation (n=2) modeling approaches. All but one (13/14) reported outcomes from payers’ perspective, while societal perspectives were also incorporated in 3 of the reviewed evaluations. One study estimated costs from a public hospital’s perspective. Only a subset of the identified studies accounted for the effects of safety (n=6) or efficacy (n=8) differences on treatment costs when estimating the costs of a formulation choice. Many studies that omitted these aspects did not include rationales for their decisions.

Conclusion

We found significant design variations in published models that estimated the impact of an additional formulation option on the treatment costs to payers and the society. Models need to be accompanied with clear descriptions on rationales for their time horizons and assumptions on how different formulations may affect healthcare costs from the selected perspectives.

Treating HIV-associated cytomegalovirus retinitis with oral valganciclovir and intra-ocular ganciclovir by primary HIV clinicians in southern Myanmar: a retrospective analysis of routinely collected data

Background

Cytomegalovirus retinitis (CMVR) is an opportunistic infection in HIV-infected people. Intraocular or intravenous ganciclovir was gold standard for treatment; however, oral valganciclovir replaced this in high-income countries. Low- and middle-income countries (LMIC) frequently use intraocular injection of ganciclovir (IOG) alone because of cost.

Methods

Retrospective review of all HIV-positive patients with CMVR from February 2013 to April 2017 at a Médecins Sans Frontièrs HIV clinic in Myanmar. Treatment was classified as local (IOG) or systemic (valganciclovir, or valganciclovir and IOG). The primary outcome was change in visual acuity (VA) post-treatment. Mortality was a secondary outcome.

Results

Fifty-three patients were included. Baseline VA was available for 103 (97%) patient eyes. Active CMVR was present in 72 (68%) eyes. Post-treatment, seven (13%) patients had improvement in VA, 30 (57%) had no change, and three (6%) deteriorated. Among patients receiving systemic therapy, four (12.5%) died, compared with five (24%) receiving local therapy (p = 0.19).

Conclusions

Our results from the first introduction of valganciclovir for CMVR in LMIC show encouraging effectiveness and safety in patients with advanced HIV. We urge HIV programmes to include valganciclovir as an essential medicine, and to include CMVR screening and treatment in the package of advanced HIV care.

Cost-effectiveness Analysis for Genotyping before Allopurinol Treatment to Prevent Severe Cutaneous Adverse Drug Reactions

OBJECTIVE

Patients with an HLA-B*58:01 allele have an increased risk of developing severe cutaneous adverse drug reactions (SCAR) when treated with allopurinol. Although one-off pharmacogenetic testing may prevent life-threatening adverse drug reactions, testing prior to allopurinol initiation incurs additional costs. The study objective was to evaluate the cost-effectiveness of HLA-B*58:01 screening compared with using other available urate-lowering agents (ULA).

METHODS

A decision-analytical model was used to compare direct medical costs and effectiveness [including lifetime saved, quality-adjusted life-yrs (QALY) gained] in treating new patients with the following options: (1) genetic screening followed by allopurinol prescribing for noncarriers of HLA-B*58:01, (2) prescribing benzbromarone without screening, (3) prescribing febuxostat without screening, and (4) prescribing allopurinol without screening. A 1-year time frame and third-party payer perspective were modeled for both the entire cohort (base-case) and for the subgroup of patients with chronic kidney disease (CKD).

RESULTS

The incremental cost-effectiveness ratio of genetic screening prior to ULA therapy was estimated as New Taiwan (NT) $234,610 (US$7508) per QALY gained in the base-case cohort. For patients with CKD, it was estimated as NT$230,925 (US$7390) per QALY. The study results were sensitive to the probability of benzbromarone/febuxostat-related hypersensitivity, and a negative predicted value of genotyping.

CONCLUSION

HLA-B*58:01 screening gave good value for money in preventing allopurinol-induced SCAR in patients indicated for ULA therapy. In addition to the costs of genotyping, it is important to monitor ULA safety closely in adopting HLA-B*58:01 screening in practice.

Spending of HIV resources in Asia and Eastern Europe: systematic review reveals the need to shift funding allocations towards priority populations

INTRODUCTION

It is increasingly important to prioritize the most cost-effective HIV interventions. We sought to summarize the evidence on which types of interventions provide the best value for money in regions with concentrated HIV epidemics.

METHODS

We conducted a systematic review of peer-reviewed and grey literature reporting measurements of cost-effectiveness or cost-benefit for HIV/AIDS interventions in Asia and Eastern Europe. We also collated HIV/AIDS spending assessment data from case-study countries in the region.

RESULTS

We identified 91 studies for inclusion, 47 of which were from peer-reviewed journals. Generally, in concentrated settings, prevention of mother-to-child transmission programmes and prevention programmes targeting people who inject drugs and sex workers had lower incremental cost-effectiveness ratios than programmes aimed at the general population. The few studies evaluating programmes targeting men who have sex with men indicate moderate cost-effectiveness. Collation of prevention programme spending data from 12 countries in the region (none of which had generalized epidemics) indicated that resources for the general population/non-targeted was greater than 30% for eight countries and greater than 50% for five countries.

CONCLUSIONS

There is a misalignment between national spending on HIV/AIDS responses and the most affected populations across the region. In concentrated epidemics, scarce funding should be directed more towards most-at-risk populations. Reaching consensus on general principles of cost-effectiveness of programmes by epidemic settings is difficult due to inconsistent evaluation approaches. Adopting a standard costing, impact evaluation, benefits calculation, analysis and reporting framework would enable cross comparisons and improve HIV resource prioritization and allocation.

Economic evaluation of HLA-B*15:02 screening for carbamazepine-induced severe adverse drug reactions in Thailand

PURPOSE

There is strong evidence of an association between the presence of the human leukocyte antigen (HLA)-B*15:02 and two severe adverse drug reactions-Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)-in patients taking carbamazepine (CBZ), a common treatment for patients with epilepsy and neuropathic pain. As a result, there are calls for all patients that are due to undergo CBZ therapy to be screened for this genetic marker before commencing their therapy. This study aims to determine the value for money of HLA-B*15:02 screening compared to the following: (1) administering CBZ therapy without conducting patient screening, and (2) not prescribing CBZ but alternative drugs that are less likely to result in severe reactions, but that come at a higher cost.

METHOD

An economic evaluation was carried out by using a decision tree and Markov models to examine the cost-utility of providing HLA-B*15:02 screening for all patients with either newly diagnosed epilepsy or neuropathic pain in the Thai setting. All transitional probabilities were derived from the national and international literature. The majority of the data on direct medical care costs were collected from 10 community, provincial, and regional hospitals throughout Thailand. Direct non-medical cost and health-related quality of life (HRQoL) data were obtained from interviews that were conducted with 33 patients, some of whom had experienced severe drug reactions.

KEY FINDINGS

The incremental cost-effectiveness ratio (ICER) of adopting a universal HLA-B*15:02 screening policy was estimated at 222,000 Thai baht, THB/quality-adjusted life year (QALY) gained for epilepsy patients and 130,000 THB/QALY gained for patients with neuropathic pain. Furthermore, we found that 343 patients need to be tested for HLA-B*15:02 allele to prevent one case of SJS/TEN.

SIGNIFICANCE

Universal HLA-B*15:02 screening represents good value for the money in terms of preventing SJS/TEN in CBZ-treated patients with neuropathic pain at the Thai ceiling ratio of 120,000 THB/QALY gained. However, the prevalence of CBZ-induced SJS/TEN in the Thai population and the positive predictive value (PPV) are major factors that influence the cost-effectiveness of HLA-B*15:02 screening. Therefore, an active surveillance system to make a more accurate assessment of the prevalence CBZ-induced SJS/TEN in the Thai population would enhance the generalizability of the results.

Pathogenesis and treatment of human immunodeficiency virus-associated cytomegalovirus retinitis

In the era of HAART, human cytomegalovirus (HCMV) retinitis remains the leading opportunistic ocular infection and the major cause of blindness in patients with AIDS. The virus has been subjected to selection and presented with the opportunity to occupy a niche to which it is highly adapted in order to escape from host immune recognition and establish persistent infection in the retina. The imbalance between host immune protection and viral immune evasion results in retinitis progression. Moreover, a synergistic interaction between HCMV and HIV in the pathogenesis of retinitis has been proposed. HAART has had a major beneficial impact on the prognosis for HIV-infected individuals. Both HAART and specific anti-HCMV treatment contribute to therapeutic success against HCMV retinitis in AIDS patients. The improved prognosis for AIDS patients with respect to the development of HCMV retinitis has been welcomed; however, we should bear in mind the occurrence of HIV drug resistance, relapse of retinitis and immune recovery uveitis after treatment, which mean that this complication of HIV infection remains a threat.

Optimal management of cytomegalovirus retinitis in patients with AIDS

Cytomegalovirus (CMV) retinitis is the most common cause of vision loss in patients with acquired immunodeficiency syndrome (AIDS). CMV retinitis afflicted 25% to 42% of AIDS patients in the pre-highly active antiretroviral therapy (HAART) era, with most vision loss due to macula-involving retinitis or retinal detachment. The introduction of HAART significantly decreased the incidence and severity of CMV retinitis. Optimal treatment of CMV retinitis requires a thorough evaluation of the patient's immune status and an accurate classification of the retinal lesions. When retinitis is diagnosed, HAART therapy should be started or improved, and anti-CMV therapy with oral valganciclovir, intravenous ganciclovir, foscarnet, or cidofovir should be administered. Selected patients, especially those with zone 1 retinitis, may receive intravitreal drug injections or surgical implantation of a sustained-release ganciclovir reservoir. Effective anti-CMV therapy coupled with HAART significantly decreases the incidence of vision loss and improves patient survival. Immune recovery uveitis and retinal detachments are important causes of moderate to severe loss of vision. Compared with the early years of the AIDS epidemic, the treatment emphasis in the post- HAART era has changed from short-term control of retinitis to long-term preservation of vision. Developing countries face shortages of health care professionals and inadequate supplies of anti-CMV and anti-HIV medications. Intravitreal ganciclovir injections may be the most cost effective strategy to treat CMV retinitis in these areas.