Pharmacological Acromegaly Treatment: Cost-Utility and Value of Information Analysis

OBJECTIVES

To conduct a cost-utility analysis comparing drug strategies involving octreotide, lanreotide, pasireotide, and pegvisomant for the treatment of patients with acromegaly who have failed surgery, from a Brazilian public payer perspective.

METHODS

A probabilistic cohort Markov model was developed. One-year cycles were employed. The patients started at 45 years of age and were followed lifelong. Costs, efficacy, and quality of life parameters were retrieved from the literature. A discount rate (5%) was applied to both costs and efficacy. The results were reported as costs per quality-adjusted life year (QALY), and incremental cost-effectiveness ratios (ICERs) were calculated when applicable. Scenario analyses considered alternative dosages, discount rate, tax exemption, and continued use of treatment despite lack of response. Value of information (VOI) analysis was conducted to explore uncertainty and to estimate the costs to be spent in future research.

RESULTS

Only lanreotide showed an ICER reasonable for having its use considered in clinical practice (R$ 112,138/US$ 28,389 per QALY compared to no treatment). Scenario analyses corroborated the base-case result. VOI analysis showed that much uncertainty surrounds the parameters, and future clinical research should cost less than R$ 43,230,000/US$ 10,944,304 per year. VOI also showed that almost all uncertainty that precludes an optimal strategy choice involves quality of life.

CONCLUSIONS

With current information, the only strategy that can be considered cost-effective in Brazil is lanreotide treatment. No second-line treatment is recommended. Significant uncertainty of parameters impairs optimal decision-making, and this conclusion can be generalized to other countries. Future research should focus on acquiring utility data.

Cost-Effectiveness and Efficacy of a Novel Combination Regimen in Acromegaly: A Prospective, Randomized Trial

CONTEXT

Combination therapy with somatostatin receptor ligand (SRL) plus pegvisomant for patients with acromegaly is recommended after a maximizing dose on monotherapy. Lower-dose combination regimens are not well studied.

OBJECTIVE

To compare cost-effectiveness and efficacy of 3 lower-dose combination regimens in controlled and uncontrolled acromegaly.

DESIGN AND SETTING

Prospective, randomized, open-label, parallel arm study at a tertiary referral pituitary center.

PATIENTS

Adults with acromegaly regardless of response to prior SRL and biochemical control status at baseline, stratified by an SRL dose required for insulin-like growth factor (IGF)-I normalization during any 3-month period within 12 months preceding enrollment.

INTERVENTION

Combination therapy for 24 to 32 weeks on arm A, high-dose SRL (lanreotide 120 mg/octreotide long-acting release [LAR] 30 mg) plus weekly pegvisomant (40-160 mg/week); arm B, low-dose SRL (lanreotide 60 mg/octreotide LAR 10 mg) plus weekly pegvisomant; or arm C, low-dose SRL plus daily pegvisomant (15-60 mg/day).

MAIN OUTCOME MEASURE

Monthly treatment cost in each arm in participants completing ≥ 24 weeks of therapy.

RESULTS

Sixty patients were enrolled and 52 were evaluable. Fifty of 52 (96%) demonstrated IGF-I control regardless of prior SRL responsiveness (arm A, 14/15 [93.3%]; arm B, 22/23 [95.7%]; arm C, 14/14 [100%]). Arm B was least costly (mean, $9837 ± 1375 per month), arm C was most expensive (mean, $22543 ± 11158 per month), and arm A had an intermediate cost (mean, $14261 ± 1645 per month). Approximately 30% of patients required pegvisomant dose uptitration. Rates of adverse events were all < 10%.

CONCLUSIONS

Low-dose SRL plus weekly pegvisomant represents a novel dosing option for achieving cost-effective, optimal biochemical control in patients with uncontrolled acromegaly requiring combination therapy.

Production of the natural iron chelator deferriferrichrysin from Aspergillus oryzae and evaluation as a novel food-grade antioxidant

BACKGROUND

Deferriferrichrysin (Dfcy) is a siderophore found in foods fermented by Aspergillus oryzae and is a promising candidate for an antioxidant food additive because of its high binding constant toward iron. However, the Dfcy concentration is typically low in foods and cultures.

RESULTS

We optimised culture conditions to improve Dfcy production to 2800 mg L(-1) from 22.5 mg L(-1) under typical conditions. Then, we evaluated the potential of Dfcy as a food additive by measuring its safety, stability, and antioxidant activity. Dfcy was sufficiently stable that over 90% remained after pasteurisation at 63 °C for 30 min at pH 3-11, or after sterilisation at 120 °C for 4 min at pH 4-6. Dfcy showed high antioxidant activity in an oil-in-water model, where inhibition of lipid oxidation was measured by peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) assays. Dfcy decreased PV and TBARS by 83% and 75%, respectively. Antioxidant activity of Dfcy was equal to or higher than that of the synthetic chelator EDTA.

CONCLUSION

Our study provides the first practical method for production of Dfcy. Dfcy can be a novel food-grade antioxidant and the first natural alternative to the synthesised iron chelator EDTA. © 2015 Society of Chemical Industry.

Optimalization and cost management of lanreotide-Autogel therapy in acromegaly

BACKGROUND

Lanreotide-Autogel is a depot formulation of the somatostatin analog lanreotide used in the treatment of acromegaly. We investigated whether prolonging or shortening the interval between injections would offer any benefit.

SUBJECTS AND METHODS

The interval was prolonged from once every 4 weeks to once every 6 weeks when patients (n=9) had normal IGF-I and GH concentrations. When patients (n=12) had still elevated IGF-I or GH on the maximal dose of 120 mg every 4 weeks, the interval was shortened to once every 3 weeks. Serum IGF-I and GH were measured after 12 and 24 weeks to allow for dose adaptation. Symptoms and tumor volume were evaluated at baseline and after 36 weeks.

RESULTS

In seven of the nine subjects with normal IGF-I and GH, the interval could be extended to 6 weeks without loosing efficacy on IGF-I (195 vs 213 microg/l; not significant, NS) and GH concentrations (1.4 vs 1.3 microg/l; NS). The weekly dose could significantly be reduced (from 23.3 to 17.8 mg; P=0.002). In only 1 of the 12 not-controlled patients, reducing the interval to once every 3 weeks induced normalization of IGF-I and GH.

CONCLUSION

In subjects whose acromegaly is well controlled using lanreotide-Autogel, prolonging the time interval between injections can often be increased 4 to 6 weeks without loss of efficacy, thereby improving the subject's comfort and reducing the cost of treatment. On the other hand, in subjects whose acromegaly is not controlled on a dose of 120 mg every 4 weeks, reducing the interval to every 3 weeks is rarely beneficial.

Economic evaluation of voriconazole versus caspofungin for the treatment of invasive aspergillosis in Spain

BACKGROUND AND OBJECTIVE

Invasive fungal infections are becoming increasingly prevalent and are more frequently the aetiological agents responsible for nosocomial infections. Since mid-2002, two new antifungal drugs - voriconazole, a third-generation azole, and caspofungin, a member of a new class of drugs called echinocandins - have been marketed in Spain. Both drugs have proven [corrected] efficacy in the treatment of aspergillosis, are better tolerated than amphotericin B and are cheaper [corrected] than liposomal amphotericin B. The objective of this study was to conduct an economic evaluation of voriconazole versus caspofungin for the treatment of invasive aspergillosis in Spain.

METHODS

This was a cost-minimisation analysis (2006 costs) from the hospital perspective. Duration of treatment and bodyweight of patients were obtained from the Fungcost study and the incidence of adverse events was obtained from different published sources. Only direct costs were considered. Mean expected cost and incremental cost were calculated, and univariate and bivariate (bodyweight/treatment duration) sensitivity analyses were conducted.

RESULTS

The mean expected cost per episode was 6041.93 euro (intravenous treatment acquisition cost 5524.75 euro) for voriconazole and 7174.05 euro (intravenous treatment acquisition cost 6672.80 euro) for caspofungin in invasive aspergillosis; the incremental cost was 1132.18 euro. Results were robust for any treatment duration and sensitive to bodyweights <103.42 kg.

CONCLUSION

Voriconazole is a more cost-effective option than caspofungin in invasive aspergillosis in patients with a bodyweight <103.42 kg.

To test or not to test: a cost minimization analysis of susceptibility testing for patients with documented Candida glabrata fungemias

This cost minimization analysis investigated the financial impact of the treatment of fungemias due to Candida glabrata from a hospital perspective using three competing alternatives: (i) performing in-house susceptibility testing on all C. glabrata isolates and changing patients to less expensive fluconazole therapy for isolates that test susceptible; (ii) susceptibility testing at outside laboratories with delayed deescalation to fluconazole if isolates test susceptible; and (iii) no routine susceptibility testing with full echinocandin treatment course. Sensitivity analyses and Monte Carlo simulation enhanced the robustness of the model through variation of all assumptions and costs. In the base case, the use of in-house testing displayed a cost advantage over the options of send-out testing and no susceptibility testing ($2,226 versus $2,410 versus $3,136, respectively). Sensitivity analyses determined that the cost of echinocandin therapy and the turnaround time for send-out testing had the potential to impact the base case model. The decision model indicated that in-house susceptibility testing of C. glabrata isolates should result in lower overall treatment costs in patients with documented C. glabrata fungemias.

Pharmacoeconomic analysis of caspofungin versus liposomal amphotericin B as empirical antifungal therapy for neutropenic fever

PURPOSE

An analysis was conducted that evaluated and compared the cost differences between caspofungin and liposomal amphotericin B when the medications were used as empirical antifungal therapy for persistent fever during neutropenia.

METHODS

Rates of drug use and impaired renal function (IRF) were based on data from published studies. IRF was defined as a doubling of the serum creatinine level or, if the creatinine level was elevated at enrollment, an increase of at least 1 mg/dL. The estimates of the costs for drug acquisition and treating IRF were derived using published data and applied to compare caspofungin with liposomal amphotericin B. Sensitivity analyses were performed by varying the IRF and relative acquisition costs to assess the effect of these factors on the cost differences.

RESULTS

The acquisition costs per patient were 6942 dollars for liposomal amphotericin B and 3996 dollars for caspofungin. The estimated cost per patient from IRF was 3173 dollars for liposomal amphotericin B and 793 dollars for caspofungin. Combining drug acquisition and IRF costs, the overall treatment cost per patient for caspofungin was 5326 dollars less than for liposomal amphotericin B. In sensitivity analyses of drug costs, the price of liposomal amphotericin B would have to be 23.95 dollars per vial for the overall treatment costs to be equal.

CONCLUSION

Comparison of cost estimates derived from published data revealed that a combined estimate of acquisition costs and costs related to the treatment of IRF was lower for caspofungin than for liposomal amphotericin B for empirically treating patients with neutropenic fever.

Micafungin: A New Echinocandin Antifungal

The echinocandins represent the newest class of antifungals to combat infections caused by Candida sp. Micafungin is an echinocandin recently approved by the United States Food and Drug Administration. It is indicated in adults for esophageal candidiasis and prophylaxis against candidal infections in hematopoietic stem cell transplant recipients. Micafungin exhibits in vitro fungicidal activity against Candida sp, including fluconazole-resistant isolates. Its in vivo efficacy is comparable to that of fluconazole in the treatment of esophageal candidiasis and superior to that of fluconazole for prophylaxis of invasive candidal infections. Because it is not significantly metabolized by the cytochrome P450 3A system, micafungin is associated with few drug interactions. Micafungin does not require adjustment in patients with renal and/or hepatic impairment, and it has been shown to be well tolerated in both adult and pediatric patients. Its efficacy against Candida sp, coupled with its overall safety and drug interaction profiles, makes it an attractive option in the treatment against esophageal candidiasis and prophylaxis against invasive candidal infections.

Peptide nucleic acid fluorescence in situ hybridization-based identification of Candida albicans and its impact on mortality and antifungal therapy costs

The impact of rapid identification of Candida albicans blood isolates by peptide nucleic acid fluorescence in situ hybridization (PNA FISH) on the selection and expenditure of antifungal therapy was evaluated. PNA FISH was 100% sensitive and specific in the rapid identification of 31 out of 72 candidemias as C. albicans and resulted in a significant reduction of caspofungin usage, with an overall cost savings of 1,729 US dollars per patient.

Cost-effectiveness analysis of antifungal treatment for patients on chemotherapy

Invasive fungal infections are fatal complications for patients on chemotherapy, and antifungal prophylactic treatment has been commonly recommended. Because its clinical and economic impact is not well known, we evaluated cost-effectiveness of anti-fungal treatment for patients who were neutropoenic as a result of chemotherapy. We constructed a hypothetical cohort of 40-year-old patients with acute myelogenic leukemia to evaluate years of life survived (YLS), costs (US$), and incremental cost-effectiveness ratio (US$/YLS). The following treatment strategies for fungal infections were compared: (1) prophylactic fluconazole strategy: oral fluconazole administration concurrently with chemotherapy; (2) empirical amphotericin B strategy: empirical intravenous amphotericin B administration at the point where fever is detected; and (3) no prophylaxis strategy: intravenous micafangin administration at the point where fungal infections is diagnosed. Baseline analyses showed that prophylactic fluconazole strategy involved higher costs but also longer YLSs (25,900 US$ and 24.08 YLS). The incremental cost-effectiveness ratio of prophylactic fluconazole strategy was 625 US$/YLS compared to no prophylaxis strategy, and 652 US$/YLS compared to empirical amphotericin B strategy. Baseline result was found to be robust through sensitivity analyses. Our study showed that concurrent administration of oral fluconazole during induction chemotherapy appears to ensure clinical benefits together with acceptable cost-effectiveness.

Cost savings with implementation of PNA FISH testing for identification of Candida albicans in blood cultures

Antifungal expenditures are substantial for many hospitals. Using caspofungin for the treatment of candidemia accounts for a sizable proportion of the costs. A cost minimization study that used a decision analytic model was done to compare in-hospital diagnosis and treatment costs using the Candida albicans peptide nucleic acid fluorescence in situ hybridization (PNA FISH) test versus the C. albicans screen test for differentiating C. albicans from non-albicans Candida species bloodstream infections. Assuming physician notification of yeast identity concurrent with blood culture positivity, potential savings resulting from use of the C. albicans PNA FISH test compared with the C. albicans screen test averaged $1837 per patient treated, although laboratory costs for doing the C. albicans PNA FISH test ($82.72) exceeded those for the C. albicans screen test ($2.83). Savings were realized through a decrease in antifungal drug costs, particularly caspofungin. Incorporating the C. albicans PNA FISH test as part of the initial identification algorithm for yeasts recovered from blood can result in substantial savings for hospitals.

Empirical anti-Candida therapy among selected patients in the intensive care unit: a cost-effectiveness analysis

BACKGROUND

Mortality from invasive candidiasis is high. Low culture sensitivity and treatment delay contribute to increased mortality, but nonselective early therapy may result in excess costs and drug resistance.

OBJECTIVE

To determine the cost-effectiveness of anti-Candida strategies for high-risk patients in the intensive care unit (ICU).

DESIGN

Cost-effectiveness decision model.

DATA SOURCES

Published data to 10 May 2005, identified from MEDLINE and Cochrane Library searches, ICU databases, expert estimates, and actual hospital costs.

TARGET POPULATION

Patients in the ICU with suspected infection who have not responded to antibacterial therapy.

TIME HORIZON

Lifetime.

PERSPECTIVE

Societal.

INTERVENTIONS

Fluconazole, caspofungin, amphotericin B, or lipid formulation of amphotericin B given as either empirical or culture-based therapy and no anti-Candida therapy.

OUTCOME MEASURES

Incremental life expectancy and incremental cost per discounted life-year (DLY) saved.

RESULTS OF BASE-CASE ANALYSIS

Ten percent of the target population will have invasive candidiasis. Empirical caspofungin therapy is the most effective strategy but is expensive (295,115 dollars per DLY saved). Empirical fluconazole therapy is the most reasonable strategy (12,593 dollars per DLY saved) and decreases mortality from 44.0% to 30.4% in patients with invasive candidiasis and from 22.4% to 21.0% in the overall target cohort.

RESULTS OF SENSITIVITY ANALYSIS

Empirical fluconazole therapy is reasonable for likelihoods of invasive candidiasis greater than 2.5% or fluconazole resistance less than 24.0%. For higher resistance levels, empirical caspofungin therapy is preferred. For low prevalences of invasive candidiasis, culture-based fluconazole is reasonable. For prevalences exceeding 60%, empirical caspofungin therapy is reasonable. For caspofungin to be reasonable at a prevalence of 10%, its cost must be reduced by 58%.

LIMITATIONS

Less severe illness and limited use of broad-spectrum antimicrobial agents, typical of smaller hospitals, could result in a lower risk for invasive candidiasis.

CONCLUSIONS

In patients in the ICU with suspected infection who have not responded to antibiotic treatment, empirical fluconazole should reduce mortality at an acceptable cost. The use of empirical strategies in low-risk patients is not justified.

[Economic evaluation of the treatment of systemic fungal infections in immunocompromised patients: the role of itraconazole]

In recent years, the incidence of HIV infection, the intensity of chemotherapy regimens for cancer and the use of bone marrow transplantation have all increased. This results in an increase in the incidence of systemic fungal infections, which are associated high rates of morbidity and mortality in this immunosuppressed population; the incidence is growing: 50% for neutropenic/transplant bone marrow patients and 5-20% for organ transplant. Fluconazole, itraconazole, amphotericin-B and, in the recent years, caspofungin and voriconazole are the most frequently used antifungal agents. However, the newly developed formulations of itraconazole and lipid-associated formulations of amphotericin-B have provide new treatment options for systemic fungal infection and have prompted a number of comparisons of the treatment costs of empirical therapy. The i.v. formulation of itraconazole may be more cost effective than either conventional or liposomial formulations of amphotericin-B when used as empirical therapy for neutropenic patients with persistent fever despite broad spectrum antibiotic therapy, but further studies are required. The lack of studies, national and international, and the small amount of available data on the cost of systemic fungal infections mean that the costs saving from prophylactic and empirical use of antifungals are difficult to estimate.

Caspofungin versus amphotericin B for candidemia: A pharmacoeconomic analysis

BACKGROUND

In a randomized, comparative, clinical trial, caspofungin was found to be as effective as amphotericin B deoxycholate (ampho B) for treating candidemia (favorable outcomes in 71.7% and 62.8% of patients, respectively) and exhibited a generally better safety profile, particularly with respect to impaired renal function (IRF) (P = 0.02).

OBJECTIVE

The goal of this study was to examine whether cost savings generated from the reduced rates of IRF observed in the clinical trial would be enough to offset the higher acquisition cost of caspofungin relative to ampho B.

METHODS

We developed an economic model in which 100 hypothetical patients with candidemia were treated with caspofungin or ampho B. Rates of IRF and duration of drug therapy were taken from the clinical trial. Information on the cost of treating IRF was obtained through a search of MEDLINE using the terms amphotericin and cost, amphotericin and resource, amphotericin and hospital, and amphotericin and toxicity; and the medical subject headings kidney failure, acute/drug therapy; kidney failure, acute/epidemiology; kidney failure, acute/etiology; kidney/drug effects; cost of illness; costs and cost analysis; kidney failure, acute, and economics; and kidney failure, acute/economics. In addition, the Web site was searched for relevant references, and the Merck publication alert system was used. Antifungal drug costs were estimated using data from IMS Health. Costs were reported in year-2003 US dollars.

RESULTS

In the base case, the model projected that using caspofungin instead of ampho B would result in substantially lower treatment costs for IRF, which would more than offset the higher drug acquisition cost (cost-offset percentage, 122%), leading to a net mean savings of 758.60 US dollars per patient. These results were not very sensitive to the difference in daily drug cost, but were sensitive to the mean cost attributable to treating IRF. As that varied, the cost-offset percentage varied from 61% (substantial cost offset) to 183% (cost savings).

CONCLUSIONS

The results of this economic model suggest that, based only on differences in drug acquisition cost and renal toxicity, the use of caspofungin instead of ampho B in patients with candidemia may be a cost-saving strategy from the perspective of a hospital.

Optimizing Somatostatin Analog Therapy in Acromegaly

Somatostatin peptide analogs have revolutionized the medical treatment of patients with acromegaly. More recent deep intramuscular depot preparations have further improved control, with consistent suppression of growth hormone secretion and optimal lowering of insulin-like growth factor-1. Effective control of growth hormone should, with long-term use, reduce morbidity and mortality from acromegaly and has been shown to result in partial involution of the pituitary adenoma in the majority of treated patients. The currently available depot formulations allow for an injection frequency of 14 days (lanreotide LA 30mg) to 28 days (octreotide LAR 20mg) according to the manufacturers' recommendations. In clinical practice, dose titration by evaluating a growth hormone day profile prior to the next injection can extend the interval between injection (to 6 or even 8 weeks in certain individuals). This is especially true for octreotide LAR, which also has increased flexibility regarding dosage with a 10 and 30mg preparation. The annual 'drug cost' is broadly similar between the two formulations though the additional expenditure on nurse time and clinic visits incurred by an increased injection frequency is a significant consideration. Decreased injection frequency improves acceptability for the patient without a loss in treatment efficacy. A subjective return of typical acromegalic symptoms, such as sweating and headache, also seem to be useful in predicting the timing of the next injection. Other formulations and doses of lanreotide are currently being evaluated, but more interestingly, newer analogs with greater efficacy at the type 5 somatostatin receptor subtype, and pan-receptor analogs, are being developed. These peptides, in conjunction with the likely availability of a growth hormone receptor blocking agent (pegvisomant), will further expand the medical therapy options for patients with acromegaly.