Once-weekly epoetin alfa for treating the anemia of chronic kidney disease

Quantitative systems pharmacology model of erythropoiesis to simulate therapies targeting anemia due to chronic kidney disease

Anemia induced by chronic kidney disease (CKD) has multiple underlying mechanistic causes and generally worsens as CKD progresses. Erythropoietin (EPO) is a key endogenous protein which increases the number of erythrocyte progenitors that mature into red blood cells that carry hemoglobin (Hb). Recombinant human erythropoietin (rHuEPO) in its native and re-engineered forms is used as a therapeutic to alleviate CKD-induced anemia by stimulating erythropoiesis. However, due to safety risks associated with erythropoiesis-stimulating agents (ESAs), a new class of drugs, prolyl hydroxylase inhibitors (PHIs), has been developed. Instead of administering exogenous EPO, PHIs facilitate the accumulation of HIF-α, which results in the increased production of endogenous EPO. Clinical trials for ESAs and PHIs generally involve balancing decisions related to safety and efficacy by carefully evaluating the criteria for patient selection and adaptive trial design. To enable such decisions, we developed a quantitative systems pharmacology (QSP) model of erythropoiesis which captures key aspects of physiology and its disruption in CKD. Furthermore, CKD virtual populations of varying severities were developed, calibrated, and validated against public data. Such a model can be used to simulate alternative trial protocols while designing phase 3 clinical trials, as well as an asset for reverse translation in understanding emerging clinical data.

Do We Store Packed Red Blood Cells under "Quasi-Diabetic" Conditions?

Red blood cell (RBC) transfusion is one of the most common therapeutic procedures in modern medicine. Although frequently lifesaving, it often has deleterious side effects. RBC quality is one of the critical factors for transfusion efficacy and safety. The role of various factors in the cells’ ability to maintain their functionality during storage is widely discussed in professional literature. Thus, the extra- and intracellular factors inducing an accelerated RBC aging need to be identified and therapeutically modified. Despite the extensively studied in vivo effect of chronic hyperglycemia on RBC hemodynamic and metabolic properties, as well as on their lifespan, only limited attention has been directed at the high sugar concentration in RBCs storage media, a possible cause of damage to red blood cells. This mini-review aims to compare the biophysical and biochemical changes observed in the red blood cells during cold storage and in patients with non-insulin-dependent diabetes mellitus (NIDDM). Given the well-described corresponding RBC alterations in NIDDM and during cold storage, we may regard the stored (especially long-stored) RBCs as “quasi-diabetic”. Keeping in mind that these RBC modifications may be crucial for the initial steps of microvascular pathogenesis, suitable preventive care for the transfused patients should be considered. We hope that our hypothesis will stimulate targeted experimental research to establish a relationship between a high sugar concentration in a storage medium and a deterioration in cells’ functional properties during storage.

A Randomized Trial of Strategies Using Darbepoetin Alfa To Avoid Transfusions in CKD

BACKGROUND

Exposure to high doses or a high cumulative dose of erythropoiesis-stimulating agents (ESAs) may contribute to cardiovascular events in patients with CKD and anemia. Whether using a low fixed ESA dose versus dosing based on a hemoglobin-based, titration-dose algorithm in such patients might reduce risks associated with high ESA doses and decrease the cumulative exposure-while reducing the need for red blood cell transfusions-is unknown.

METHODS

In this phase-3, randomized trial involving 756 adults with stage-3 to -5 CKD and anemia, we evaluated incidence of red blood cell transfusions for participants randomized to receive darbepoetin given as a fixed dose (0.45 µg/kg every 4 weeks) versus administered according to a hemoglobin-based, titration-dose algorithm, for up to 2 years. Participants received transfusions as deemed necessary by the treating physician.

RESULTS

There were 379 patients randomized to the fixed-dose group, and 377 to the titration-dose group. The percentage of participants transfused did not differ (24.1% and 24.4% for the fixed-dose and titration-dose group, respectively), with similar time to first transfusion. The titration-dose group achieved significantly higher median hemoglobin (9.9 g/dl) compared with the fixed-dose group (9.4 g/dl). The fixed-dose group had a significantly lower median cumulative dose of darbepoetin (median monthly dose of 30.9 µg) compared with the titration-dose group (53.6 µg median monthly dose). The FD and TD group received a median (Q1, Q3) cumulative dose per 4 weeks of darbepoetin of 30.9 (21.8, 40.0) µg and 53.6 (31.1, 89.9) µg, respectively; the median of the difference between treatment groups was -22.1 (95% CI, -26.1 to -18.1) µg.

CONCLUSIONS

These findings indicate no evidence of difference in incidence of red blood cell transfusion for a titration-dose strategy versus a fixed-dose strategy for darbepoetin. This suggests that a low fixed dose of darbepoetin may be used as an alternative to a dose-titration approach to minimize transfusions, with less cumulative dosing.

Patient-Centred Outcomes in Anaemia and Renal Disease: A Systematic Review

Background

Anaemia is a nearly universal complication of chronic kidney disease (CKD). Erythropoiesis-stimulating agents (ESAs) have been demonstrated to improve clinical outcomes and quality of life (QOL) in renal patients with anaemia. Patient-reported outcome measures (PROMs) are increasingly being used to evaluate the patient-centred impact of medical therapy. Here, we describe a systematic review of studies that evaluated patient-centred outcomes (PCOs) in renal patients undergoing anaemia treatment.

Methods

We conducted a search of Medline (Ovid), EMBASE (Ovid), PsychINFO, and CINAHL databases for studies published until March 2018 that investigated an intervention to treat anaemia in renal patients and used at least one PROM. We also performed a quality assessment for all included studies. Statistical analyses characterized each study, PROMs used, the quality of PCO reporting, and the association between haematological outcomes and PCOs.

Results

Of the 3,533 studies identified in the database search, 21 met all eligibility criteria. Fourteen (67%) of the studies were randomized-controlled trials. Most studies (81%) investigated CKD patients, 14% investigated post-renal transplant patients and 5% assessed patients with heart disease on haemodialysis. The most common anaemia intervention, used in 95% of studies, was ESAs. Forty-three percent of studies utilized one PROM, most commonly the SF-36, a measure of QOL not specifically created for use in nephrology patients. About a third of studies selectively reported PROM subscales, rather than reporting all subscales. Notable biases among included studies included lack of blinding, selective outcome reporting, and lack of power estimates for PCOs. We did not find a statistically significant association between improvements in haemoglobin and QOL.

Conclusions

Future studies employing anaemia and nephrology-specific PROMs and conducted with greater rigour, standardization in the research methods, and reporting of PCOs in renal populations will improve understanding of PCOs in this patient group and hopefully improve patient outcomes and experiences.

Economic Burden and Health-Related Quality of Life Associated with Current Treatments for Anaemia in Patients with CKD not on Dialysis: A Systematic Review

BACKGROUND

The cost and health-related quality of life (HRQoL) burden associated with treatments for anaemia of chronic kidney disease (CKD) is not well characterized among non-dialysis-dependent (NDD) patients.

OBJECTIVE

Our objective was to review the literature on costs and HRQoL associated with current treatments for anaemia of CKD among NDD patients.

METHODS

The Cochrane Library, MEDLINE, Embase, NHS EED, and NHS HTA databases were searched for original studies published in English between 1 January 2000 and 17 March 2017. The following inclusion criteria were applied: adult population; primary focus was anaemia of CKD; patients received iron supplementation, red blood cell transfusion, or erythropoiesis-stimulating agents (ESAs); and reported results on HRQoL and/or costs. Studies that included NDD patients, did not compare different treatments, and had relevant designs were retained. HRQoL and cost outcomes were summarized in a narrative synthesis.

RESULTS

In total, 16 studies met the inclusion criteria: six randomized controlled trials, four prospective single-arm trials, three retrospective studies, one prospective observational study, one simulation study, and one cross-sectional survey. All included ESAs. Treatment of anaemia (compared with no treatment) was associated with HRQoL improvements in five of six studies and lower costs in four of four studies. Treatment aiming for higher haemoglobin targets (compared with lower targets) resulted in modest HRQoL improvements, higher healthcare resource utilization (HRU), and higher costs.

CONCLUSIONS

In NDD patients, untreated anaemia of CKD leads to higher costs, higher HRU, and lower HRQoL compared with initiating anaemia treatment. Relative to aiming for lower haemoglobin targets with ESAs, higher targets conferred modest HRQoL improvements and were associated with higher HRU.

De novo weekly and biweekly darbepoetin alfa dosing in pediatric patients with chronic kidney disease

BACKGROUND

Darbepoetin alfa is a commonly prescribed erythropoiesis-stimulating agent (ESA) for correcting anemia in pediatric chronic kidney disease (CKD) patients. However, little information exists on its use in ESA-naïve patients. This study evaluated the efficacy and safety of darbepoetin alfa in pediatric patients initiating ESA therapy.

METHODS

One-hundred sixteen pediatric ESA-naïve subjects (aged 1-18 years) with CKD stages 3-5D and hemoglobin (Hb) <10 g/dl from 43 centers in the US, Europe, and Mexico were randomized by age (three groups) and dialysis status (yes vs. no) to receive darbepoetin alfa once weekly (QW) or every 2 weeks (Q2W) subcutaneously (not on dialysis and peritoneal dialysis subjects) and intravenously (hemodialysis subjects). The drug was titrated to achieve Hb levels of 10.0-12.0 g/dl over 25 weeks. Patient- and parent-reported health-related outcomes were measured by the Pediatric Quality of Life Inventory (PedsQL™) in children ≥2 years.

RESULTS

In both groups, mean Hb concentrations increased to ≥11.0 g/dl over the first 3 months of treatment and remained stable within the 10.0-12.0 g/dl target range. The median time to achieve hemoglobin ≥10 g/dl was slightly longer for subjects <12 years (QW and Q2W, both 28 days) vs. those ≥12 years (23 and 22 days, respectively). Adverse event profiles were similar between groups, with QW, four (7%) and Q2W, five (9%). PedsQL™ scores showed modest increases.

CONCLUSIONS

Darbepoetin alfa can be safely administered either QW or Q2W to ESA-naïve pediatric patients with CKD-related anemia to achieve Hb targets of 10.0-12.0 g/dl.

Assessment of erythropoietin for treatment of anemia in chronic kidney failure- ESRD patients

BACKGROUND AND OBJECTIVE

Currently there is an inadequate data regarding effective management of anemia in chronic kidney disease (CKD) patients who are on dialysis. In CKD patients' anemia mainly develops from decreased renal synthesis of erythropoietin (EPO) and iron deficiency. Our current study focused to effective management of anemia in CKD patients'.

STUDY DESIGN

Prospective observational case series study.

METHODS

Eligible patients were assigned to three study groups according to initial hemoglobin level i.e. Group I having Hb level below 11g/dL, Group II with Hb level of 11-13g/dL, and Group III with Hb level more than 13g/dL. Intravenous dosing of ESA's calculated according to the range of 150-300IU or equivalent microgram quantity per kilogram body weight was administered to patients in divided doses per week; alone or in combination with iron supplements.

RESULTS

Study population (n=163; 100%), of which 124 subjects (76%) patients were treated with erythropoietin and iron supplements; rest of 39 (24%) patients were treated with only erythropoietin. The estimation of hemoglobin content revealed Group I (98 patients) Hb were increased significantly from 9.0±1.2g/dl at baseline to 10.9±1.7g/dl. No significant changes in Group II and Group III were observed.

CONCLUSIONS

Study suggests use of erythropoietin along with iron for treatment of renal failure associated anemia is more beneficial for CKD patients having low Hb. Also study conclude the use of lower than normal dose (150-300IU) of ESA is appropriate when hemoglobin reaches 11g/dl in hemodialysis patients.

How Can We Improve the Quality of Life of Dialysis Patients?

As medical advances are made in the care of persons with chronic illnesses including those with end-stage renal disease (ESRD), patients are not only experiencing increasing life expectancy but also bearing the burden of illness and treatment for a longer duration of time. With this in mind, it is increasingly important for health care providers to pay close attention to their individual patient's perceptions of their health, fitness, life satisfaction, and well-being. This assessment of Health-Related Quality of Life (HRQOL) also includes an evaluation of the patient's level of satisfaction with treatment, outcome, and health status, also taking into account their perspective on future prospects. In addition to improving patient-provider communication by helping in the identification and prioritization of problems, it is important to note that high HRQOL has been shown to be associated with better medical outcomes, including reduction in hospitalizations and death. In this review, we outline several validated tools that are used to quantitatively measure HRQOL in the ESRD population and incorporate these instruments in a review of specific, evidence-based measures by which we can measurably improve health-related quality of life in dialysis patients.

Use of Erythropoietin-Stimulating Agents (ESA) in Patients With End-Stage Renal Failure Decided to Forego Dialysis: Palliative Perspective

Normochromic normocytic anemia is a common complication in chronic kidney disease (CKD) and is associated with many adverse clinical consequences. Erythropoiesis-stimulating agents (ESAs) act to replace endogenous erythropoietin for patients with end-stage renal disease having anemia. Today, ESAs remain the main tool for treating anemia associated with CKD. In current practice, the use of ESA is not limited to the patients on renal replacement therapy but has extended to nondialysis patients under palliative care (PC). Current evidence on ESA usage in patients with CKD decided to forego dialysis often have to take reference from studies conducted in other groups of patients with CKD, including pre-dialysis patients and those on renal replacement therapy. There is paucity of studies targeting use of ESAs in renal PC patients. Small-scale retrospective study in renal PC patients had suggested clinical advantage of ESAs in terms of hemoglobin improvement, reduction in fatigue, and hospitalization rate. With the expected growth in elderly patients with CKD decided to forego dialysis and manage conservatively, there remains an urgent need to call for large-scale prospective trial in exploring efficacy of ESAs in this population, targeting on quality of life and symptoms improvement outcome. This article also reviews the mechanism of action, pharmacology, adverse effects, and clinical trial evidence for ESA in patients with CKD under renal PC.

Differentiating factors between erythropoiesis-stimulating agents: an update to selection for anaemia of chronic kidney disease

Erythropoiesis-stimulating agents (ESAs) have become a hallmark of anaemia therapy in patients with chronic kidney disease (CKD). Although different ESAs are available for the treatment of renal anaemia, each nephrologist should select a single ESA for an individual patient. Epoetin alfa and epoetin beta have been used 1-3 times weekly but extended-interval dosing up to every 4 weeks is also effective in a substantial majority of CKD patients. However, the epoetin dose necessary to achieve or maintain target haemoglobin (Hb) levels increases substantially as the dosing interval increases. Subcutaneous administration of short-acting ESAs is more effective than the intravenous route of administration. Darbepoetin alfa and the continuous erythropoietin receptor activator (CERA) have been developed as a treatment for anaemia with extended administration intervals (every 2 weeks and every 4 weeks, respectively). Dose requirements for these long-acting ESAs are independent of the route of administration. Patents of short-acting ESAs have expired, which has opened the field for biosimilars. Epoetin biosimilars approved by the European Medicines Agency (EMA) or the US Food and Drug Administration (FDA) have been shown to have a comparable efficacy and safety profile to their originators. An alarming increase in pure red cell aplasia (PRCA) in Thailand with follow-on epoetins manufactured in Asia (but also those manufactured in Latin America) indicates that stringent country-specific approval and pharmacovigilance protocols for ESAs manufactured in non-North American and non-EU European countries are urgently needed. Two PRCA cases occurring with subcutaneous HX575 (one certain, one likely) indicate that chances of inducing a more immunogenic product are unpredictable, even with a biosimilar epoetin approved under the EMA biosimilar approval pathway. Phase III clinical trials with peginesatide, a pegylated synthetic peptide-based ESA without any homology to erythropoietin raised safety concerns in non-dialysis CKD patients but not in dialysis patients.

Red blood cell transfusion use in patients with chronic kidney disease

BACKGROUND

There is limited data available on the use of red blood cell (RBC) transfusions in younger chronic kidney disease patients not on dialysis (CKD-ND), for whom the consequences of developing antibodies to foreign antigens (allosensitization) may be particularly relevant.

METHODS

We used the Ingenix medical claims database, comprising data on ∼40 million commercially insured US individuals, to identify annual (2002-08) cohorts of patients 18-64 years of age with newly diagnosed CKD. We followed each cohort for 1 year to estimate RBC transfusion rates and used Cox proportional hazards regression to identify patient characteristics associated with time to first transfusion.

RESULTS

We identified 120 790 newly diagnosed CKD patients for the years 2002-08; 54% were 50-64 years of age. Overall, the transfusion rate was 2.64/100 person-years (PYs) (95% CI: 2.52-2.77). Rates were higher among those with diagnosed anemia [9.80/100 PYs (95% CI: 9.31-10.3)] and among those who progressed to end-stage renal disease (ESRD) [28.0/100 PYs (95% CI: 23.7-33.0)]. For those progressing to ESRD, transfusion rates more than doubled between 2002 and 2008. Of the factors evaluated, transfusion history and the presence of heart failure and diabetes were most strongly associated with a receipt of a transfusion.

CONCLUSIONS

RBC transfusions are relatively common and on the rise among younger CKD-ND patients who are anemic and progress to ESRD. Efforts to decrease the use of transfusions may be important for potential transplant candidates who progress to ESRD.

Epoetin theta: efficacy and safety of subcutaneous administration in anemic pre-dialysis patients in the maintenance phase in comparison to epoetin beta

OBJECTIVE

To compare the efficacy and safety of epoetin theta and epoetin beta in anemic patients with chronic kidney disease (CKD) not yet receiving dialysis and previously on stable maintenance therapy with epoetin beta.

METHODS

In this multicenter, randomized, controlled, double-blind, non-inferiority study, 288 patients were treated subcutaneously (s.c.) for 24 weeks with epoetin theta (n = 193) or epoetin beta (n = 95). The primary efficacy endpoint was change in hemoglobin (Hb) from a 2-week baseline period to end of treatment (12-week efficacy evaluation period [EEP], weeks 15-26). The non-inferiority limit was 1.0 g/dL (2-sided alpha = 0.05). Weekly doses of epoetin required to maintain Hb levels, dose changes, safety, tolerability, and immunogenicity were also evaluated.

CLINICAL TRIAL REGISTRATION

EudraCT No. 2005-000142-37.

RESULTS

Mean Hb values were comparable in both groups at baseline and during the 24-week treatment period. The estimated treatment difference between groups from baseline to EEP was 0.01 g/dL (95% confidence interval: -0.20, 0.22; p = 0.9207 (ANCOVA)), indicating that epoetin theta was non-inferior to epoetin beta. The weekly doses of epoetin theta or epoetin beta were nearly the same and the change from baseline to EEP in patients who switched to epoetin theta (36.6 to 30.0 IU/kg(BW)) was comparable to those continuing epoetin beta therapy (37.7 to 28.3 IU/kg(BW)). The profile and the frequency of adverse drug reactions (ADRs) were comparable in both groups (17.1% epoetin theta; 14.7% epoetin beta). The most common ADR was hypertension. No patient developed anti-erythropoietin antibodies.

CONCLUSIONS

Epoetin theta (s.c.) has efficacy comparable with epoetin beta (s.c.) in pre-dialysis patients with renal anemia based on Hb changes from baseline to end of treatment (non-inferiority). The safety profile was also comparable. Patients could be switched from maintenance treatment with epoetin beta to epoetin theta without relevant dose changes.

Utilization and cost comparison of erythropoiesis-stimulating agents in inpatient and outpatient hospital settings

OBJECTIVE

To compare utilization and associated costs of epoetin alfa (EPO) and darbepoetin alfa (DARB), two erythropoiesis-stimulating agents (ESAs), in patients with cancer undergoing chemotherapy and patients with chronic kidney disease (CKD) not on dialysis in inpatient and outpatient hospital settings.

METHODS

An analysis of medical claims recorded between January 2006 and December 2009 was conducted using the Premier Perspective Comparative Hospital database. Patients included were ≥18 years old with cancer and chemotherapy or with pre-dialysis CKD and with ≥1 claim for EPO or DARB during a hospital inpatient or outpatient treatment episode. Patients treated with both ESAs or who were receiving dialysis were excluded. Mean cumulative drug costs and dose ratios (units EPO: mcg DARB) were calculated using cumulative dose and April 2010 wholesale acquisition costs.

RESULTS

Cancer chemotherapy: 13,832 inpatient stays (EPO: 10,454; DARB: 3378) and 5590 outpatient treatment episodes (EPO: 2856; DARB: 2734) were identified. The inpatient and outpatient populations reported ESA dose ratios of 230:1 and 238:1 with DARB cost premiums of 42% (EPO: $948; DARB: $1348) and 38% (EPO: $3358; DARB: $4627), respectively. CKD: 148,746 hospital stays (EPO: 116,017; DARB: 32,729) and 11,012 outpatient treatment episodes (EPO: 6921; DARB 4091) were identified. The inpatient and outpatient populations reported ESA dose ratios of 251:1 and 257:1 with DARB cost premiums of 30% (EPO: $566; DARB: $738) and 27% (EPO: $2077; DARB: $2642), respectively.

LIMITATIONS

The lack of randomization may have led to confounding by indication. In addition, statistical significance must be interpreted with caution in studies involving large samples.

CONCLUSIONS

This study of 19,422 patients with cancer receiving chemotherapy and 159,758 patients with pre-dialysis CKD reported ESA dose ratios ranging from 230:1-257:1 (units EPO: mcg DARB) and associated cost premiums of 27-42% for DARB.

Understanding and assessing the impact of end-stage renal disease on quality of life: a systematic review of the content validity of self-administered instruments used to assess health-related quality of life in end-stage renal disease

Advances in healthcare, combined with an increasing number of adults with end-stage renal disease (ESRD), mean that there is a growing number of people now surviving on renal replacement therapy. The issue of health-related quality of life (HR-QOL) is becoming increasingly important in this area. For this reason, the content validity of various instruments used to measure HR-QOL in an ESRD population were explored. Systematic searches of MEDLINE (1950-2009) were conducted using terms related to ESRD combined with terms associated with measuring HR-QOL. A total of 378 abstracts were identified, detailing the repeated use of six generic measures and four disease-specific measures. The generic HR-QOL measures discussed include the Medical Outcomes 36-Item Short Form Survey (SF-36), the EuroQOL 5 Dimension (EQ-5D), and the WHO QOL assessment (WHOQOL-BREF). The most frequently used disease-specific measure discussed is the Kidney Disease QOL instrument (KDQOL) and its derivative versions (KDQOL-SF, KDQOL-36). The appropriateness of using the SF-36 in this population is challenged and recommendations include using the WHOQOL-BREF in cases when a generic instrument is required and the KDQOL-SF when a more disease-specific measurement is called for.

An open-label, randomized, multicenter, controlled study of epoetin alfa for the treatment of anemia of chronic kidney disease in the long term care setting

OBJECTIVE

To evaluate the safety and efficacy of epoetin alfa administered in extended-dosing intervals to a target hemoglobin (Hb) level not exceeding 12.0 g/dL for the treatment of anemia in subjects with chronic kidney disease (CKD) not on dialysis.

DESIGN

An open-label, randomized, multicenter, controlled study consisting of a 1-week screening phase and a 26-week open-label treatment phase.

SETTING

Twenty-seven long term care (LTC) facilities in the United States.

PARTICIPANTS

Subjects with CKD who were not receiving dialysis, who had not received an erythropoiesis-stimulating agent for 8 weeks before screening, and whose Hb levels were lower than 11.0 g/dL at screening were eligible.

INTERVENTION

In the epoetin alfa group, subjects were administered 20,000 international units epoetin alfa subcutaneously every 2 weeks (Q2W). Dosing was based on the Hb concentration measurement obtained by HemoCue Hb201+System (Quest Diagnostics; Madison, NJ) at the time of the scheduled dose. When the Hb concentration was 11.0 to 11.5 g/dL on 2 consecutive biweekly measurements, the dose was doubled and administered on the day that the second consecutive measurement was obtained. The dosing interval was then extended to every 4 weeks (Q4W). Subjects in the standard of care (SOC) group received treatment for their anemia according to the practice of the LTC facility.

MEASUREMENTS

Study visits were every 2 weeks, at which time blood was drawn and used for efficacy analysis. Measurements included: the Hb concentration change from baseline to the end of the study; the proportion of subjects who achieved an Hb response (defined as 2 consecutive Hb measurements at least 1.0 g/dL greater than baseline or 2 consecutive Hb measurements ≥11.0 g/dL at any time during the study); the time to the Hb response; the proportion of subjects who received a transfusion and the number of units of transfused; the proportion of epoetin alfa-treated subjects converting to Q4W dosing; and the proportion of subjects who converted to Q4W dosing and remained on Q4W dosing through the end of the study.

RESULTS

A total of 157 subjects were randomized: 118 subjects to the epoetin alfa group and 39 to the SOC group. The mean change in Hb was significantly greater in the epoetin alfa group (0.9 g/dL) compared with the SOC group (0.3 g/dL) (P = .006). A significantly greater percentage of subjects achieved a Hb response in the epoetin alfa group (85.1%) compared with the SOC group (53.8%) (P < .001). The time to achieve a Hb response was significantly shorter in the epoetin alfa group (41 days) than in the SOC group (114 days) (P < .0001). There were no transfusions in the SOC group, whereas 4 subjects (3.5%) required transfusions in the epoetin alfa group. Of the 114 subjects receiving epoetin alfa, 33 (28.9%) subjects were converted to Q4W dosing, and all subjects who converted were able to be maintained on this schedule.

CONCLUSIONS

The administration of epoetin alfa in extended-dosing intervals of Q2W followed by Q4W was safe and effective in the treatment of anemia in subjects with CKD who reside in LTC facilities.

A randomized controlled study comparing once-weekly to every-2-week and every-4-week dosing of epoetin alfa in CKD patients with anemia

BACKGROUND AND OBJECTIVES

Extended-interval dosing of epoetin alfa (EPO) is commonly used to treat anemia in patients with chronic kidney disease (CKD). This study aimed to demonstrate that EPO dosed every 2 weeks (Q2W) and every 4 weeks (Q4W) was noninferior to once-weekly (QW) dosing.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

430 anemic subjects with stage 3 to 4 CKD receiving a stable QW dose of EPO were randomized 1:1:2 to QW, Q2W, and Q4W dosing for 36 weeks. Hemoglobin (Hb) was measured weekly, and the dose of EPO was adjusted to maintain an Hb level of 11.0 to 11.9 g/dl. The primary endpoint was change in Hb from baseline to the average of the last 12 weeks of treatment.

RESULTS

Both the Q2W and Q4W dosing groups were noninferior to the QW group. The estimated difference of the mean change in Hb between Q2W and QW was -0.03 g/dl; and between Q4W and QW was -0.09 g/dl. From weeks 13 to 37, the mean percentage of weeks per subject with Hb 10.0 to 11.9 g/dl, inclusive, was 81% for QW, 81% for Q2W, and 75% for Q4W. Death occurred, respectively, in 4%, 3%, and 4%; thromboembolic vascular events occurred in 3%, 5%, and 3%; and serious adverse events occurred in 22%, 26%, and 26% of subjects.

CONCLUSIONS

Q2W and Q4W EPO dosing maintained Hb levels in subjects with stage 3 to 4 CKD. Deaths, thromboembolic vascular events, and serious adverse events were comparable across the dosing groups.

Burden of illness for patients with non-dialysis chronic kidney disease and anemia in the United States: review of the literature

OBJECTIVE

To assess the health-related quality of life (HRQL) and economic burden of chronic kidney disease (CKD) related anemia in non-dialysis patients in the United States (US) via literature review.

METHODS

MEDLINE, EMBASE, PROQOLID, and Cochrane Library/Renal Group Resources were searched. Studies were appraised for patient populations, disease-specific versus generic HRQL assessments, and type and magnitude of health-related costs.

RESULTS

The treatment costs for CKD patients with anemia compared to those without anemia were significantly higher and were blunted but persistent after controlling for comorbidities and confounders. Intervention with erythropoiesis stimulating agents (ESA) decreased anemia and avoided hospital admissions. Costs were higher when anemia was poorly controlled or untreated. HRQL burden was mainly due to physical limitations and difficulty in ability to perform activities of daily living. Significant positive correlations between increases in hemoglobin levels and HRQL measures were reported.

CONCLUSIONS

Although evidence is limited, the economic and HRQL burden of non-dialysis CKD-related anemia is substantial. Under-treatment of anemia may contribute to higher resource consumption and higher costs; however, patient co-morbidities, use of erythropoietin-stimulating agents, and overall management introduce potential confounds. The contribution of anemia to humanistic disease burden is due to a constellation of factors, including physical activity and functional status.

A randomized controlled study of weekly and biweekly dosing of epoetin alfa in CKD Patients with anemia

BACKGROUND AND OBJECTIVES

In clinical practice, physicians often use once-weekly (QW) and biweekly (Q2W) dosing of epoetin alfa to treat anemia in patients with chronic kidney disease (CKD). Although the literature supports this practice, previous studies were limited by short treatment duration, lack of randomization, or absence of the approved three times per week (TIW) dosing arm. This randomized trial evaluated extended dosing regimens of epoetin alfa, comparing QW and Q2W to TIW dosing in anemic CKD subjects. The primary objective was to show that treatment with epoetin alfa at QW and Q2W intervals was not inferior to TIW dosing.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

375 subjects with stage 3 to 4 CKD were randomized equally to the three groups and treated for 44 wk; to explore the impact of changing from TIW to QW administration on hemoglobin (Hb) control and adverse events, subjects on TIW switched to QW after 22 wk. The Hb was measured weekly, and the dose of epoetin alfa was adjusted to achieve and maintain an Hb level of 11.0 to 11.9 g/dl.

RESULTS

Both the QW and Q2W regimens met the primary efficacy endpoint. More subjects in the TIW group than in the QW and Q2W groups exceeded the Hb ceiling. Adverse events were similar across treatment groups and consistent with the morbidities of CKD patients.

CONCLUSIONS

Administration of epoetin alfa at QW and Q2W intervals are potential alternatives to TIW dosing for the treatment of anemia in stage 3 to 4 CKD subjects.

Managing Anemia of Chronic Kidney Disease

Anemia begins early in the course of declining kidney function and is a frequent complication of chronic kidney disease. Both anemia and chronic kidney disease are underdiagnosed and undertreated. Anemia is associated with significantly increased risk of morbidity and mortality, including increased risks of left ventricular hypertrophy and heart failure. Although the detrimental effects of anemia are more common in patients with advanced chronic kidney disease, it has been suggested that correcting anemia in early stage kidney disease may improve health-related quality of life and also delay the progression to end-stage kidney disease. The identification of anemia in early stage chronic kidney disease and its aggressive management may also improve cardiovascular complications. Anemia of chronic kidney disease is predominantly a result of abnormal erythropoietin production and iron deficiency. Anemia may be the result of kidney failure itself, blood losses, nutritional deficiencies, and endocrine disorders. Guidelines and protocols for treating anemia can assist practitioners in identifying patients with anemia, treating anemia, evaluating response to treatment, and modifying treatment based on response. Erythropoeisis-stimulating agents have been shown to be effective in treating anemia in predialysis and dialysis patients. Iron supplementation is usually required in patients receiving erythropoeisis-stimulating agent therapy or with iron deficiency. Successfully managing anemia of chronic kidney disease with treatment strategies that accommodate patient lifestyle and improve compliance is paramount. Primary care physicians play an important role in the care of patients with kidney disease, as does collaboration with other medical professionals involved in their care.

Health-related quality of life and hemoglobin levels in chronic kidney disease patients

BACKGROUND

The relationship between quality of life (QofL) and anemia has been the subject of recent debates; it has been suggested that the QofL changes associated with the treatment of anemia of chronic kidney disease (CKD) or ESRD patients should not be used in making decisions to treat anemia in CKD patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This study examines the relationship between Kidney Disease Quality of Life (KDQofL) questionnaire domains and hemoglobin (Hgb) levels in 1200 patients with stage 3, 4, and 5 CKD followed in seven centers. QofL measures were compared in a stepwise fashion for hemoglobin levels of <11, 11 to <12, 12 to <13, and > or =13. ANOVA was used to examine the relationship between QofL scores and Hgb level, age, CKD stage, and albumin level; a history of diabetes, congestive heart failure, or myocardial infarction; use of erythropoetic-stimulating agents (ESA); and the interaction of hemoglobin level and ESA.

RESULTS

The results demonstrate that with increasing Hgb levels there is a statistically significant increase in all four physical domains, the energy/vitality domain, and the physical composite score of the SF-36, and the general health score on the kidney disease component of the questionnaire. The most dramatic improvements in these various domains occurred between the <11 and the 11 to 12 group.

CONCLUSIONS

Higher Hgb levels are associated with improved QofL domains of the KDQofL questionnaire. These findings have implications for the care of CKD patients in terms of the initiation of and the Hgb target of ESA therapy.

Interpretation and review of health-related quality of life data in CKD patients receiving treatment for anemia

Recent evidence suggests that targeting higher hemoglobin values with erythropoiesis stimulating agents (ESAs) may lack mortality benefits and may even result in adverse cardiovascular complications when used in chronic kidney disease patients. However, ESAs are frequently reported to result in improvements in health-related quality of life (HRQOL). The purpose of this review is to evaluate the magnitude and nature of ESA-associated improvements in HRQOL, as well as to understand how to interpret the clinical significance of HRQOL data. HRQOL findings should be analyzed not by statistical significance but rather by using a minimal clinically important difference approach, or, alternatively, a distribution-based approach (such as Cohen's effect size). HRQOL domains that are most improved with ESAs relate to physical symptoms, vitality, energy, and performance; domains of social functioning and mental health show modest improvement, whereas the domains of emotional functioning and pain show very little improvement. Additional domains not measured by commonly used instruments (such as the SF-36) that have been shown to improve with ESAs include sleep, cognitive functioning, and sexual functioning. The maximal increase in HRQOL per incremental increase in hemoglobin appears to occur in the range of 10-12 g/dl. Beyond this range, additional normalization of hemoglobin (to 12-14 g/dl) results in continued (albeit blunted) improvements in HRQOL.

A randomized study of extended dosing regimens for initiation of epoetin alfa treatment for anemia of chronic kidney disease

BACKGROUND AND OBJECTIVES

Although epoetin alfa is commonly initiated weekly (QW) in anemic chronic kidney disease (CKD) patients, recent evidence indicates that it can be initiated every 2 wk (Q2W) and used in maintenance therapy every 4 wk (Q4W). This study examined the feasibility of initiating epoetin alfa Q4W in anemic CKD patients not receiving dialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This open-label study randomized subjects (1:2:2:2) to treatment with epoetin alfa 10,000 IU QW, 20,000 IU Q2W, 20,000 IU Q4W, or 40,000 IU Q4W for 16 wk. Subjects were > or =18 yr, had hemoglobin <11 g/dl, a glomerular filtration rate of 15 to 90 ml/min per 1.73 m(2), and had not received erythropoietic therapy within 8 wk. The primary analysis was a noninferiority comparison of the 40,000 IU Q4W to the 20,000 IU Q2W group in the per-protocol population with respect to hemoglobin change from baseline to the end of study.

RESULTS

Of 262 subjects randomized, 229 comprised the per-protocol population. Mean hemoglobin change from baseline for the 40,000 IU Q4W group (1.24 g/dl) was not inferior to the 20,000 IU Q2W group (1.11 g/dl) with the lower limit of 95% CI, -0.21 g/dl. In the QW, 20,000 IU Q2W, 20,000 IU Q4W, and 40,000 IU Q4W groups, 90%, 87%, 75%, and 86% of subjects, respectively, achieved a hemoglobin increase > or =1 g/dl. Serious adverse events were similar across all groups.

CONCLUSIONS

Epoetin alfa can be initiated Q4W in anemic CKD subjects.

Effect of darbepoetin alfa administered once monthly on maintaining hemoglobin levels in older patients with chronic kidney disease

BACKGROUND

The anemia of chronic kidney disease (CKD) is associated with increased hospitalizations, increased cardiovascular morbidity and mortality, and diminished quality of life in the elderly. Darbepoetin alfa is an erythropoiesis-stimulating agent that has been shown to be effective in treating anemia in patients with CKD (but not on dialysis) when administered using extended-dosing regimens.

OBJECTIVE

The purpose of this post hoc analysis was to examine the efficacy and safety profile of once-monthly (QM) darbepoetin alfa in study patients stratified according to age (ie, <65, 65-74, and > or =75 years).

METHODS

Patients with CKD but not on dialysis, receiving darbepoetin alfa every other week (Q2W), and with stable hemoglobin (Hb) levels between 11 and 13 g/dL, inclusive, were enrolled in this 33-week, multicenter, open-label, single-arm study. The study was carried out at 36 US centers and consisted of a 24-week QM darbepoetin alfa dose-titration period followed by an 8-week evaluation period. Hb levels were measured Q2W. Study results were stratified according to patient age (<65, 65-74, and > or =75 years).

RESULTS

A total of 152 patients (79 women, 73 men) were enrolled; 55 patients (36%) were <65 years of age, 46 (30%) were 65 to 74 years of age, and 51 (34%) were > or =75 years of age. In patients who received > or =1 dose of darbepoetin alfa, Hb levels > or =11 g/dL were maintained in 76%, 80%, and 71% of patients aged <65, 65 to 74, and > or =75 years, respectively. For patients who completed the study, the proportions who maintained Hb levels > or =11 g/dL were 83%, 88%, and 85%, respectively, for the 3 age groups. The safety profile of QM darbepoetin alfa in this study was consistent with that expected in patients with CKD not receiving dialysis.

CONCLUSIONS

Darbepoetin alfa administered QM maintained Hb levels > or =11 g/dL in patients with CKD (not on dialysis) aged <65, 65 to 74, and > or =75 years. This treatment regimen may help optimize anemia management for older community-dwelling and long-term care patients.

Anemia of Chronic Kidney Disease

Chronic kidney disease may result in complete kidney failure and contribute to many other health issues. Anemia is a logical consequence of the disease because the kidneys are the primary source of erythropoietin, the hormone that acts to stimulate red blood cell production in the bone marrow. All patients with chronic kidney disease are at risk for anemia, and treating anemia is extremely important to their health and well-being. Preventing or reversing the effects of anemia on the heart may decrease morbidity and mortality and improve quality of life. Many patients fail to receive treatment for anemia before requiring renal replacement therapy for end-stage renal disease. Pharmacists can play a vital role in screening, evaluating, designing proper treatment regimens, and monitoring patients with anemia of chronic kidney disease. Current recommendations regarding anemia are reviewed, including evaluation, pharmacotherapeutic agents, monitoring parameters, and goals of therapy.

Pharmacokinetic and pharmacodynamic profiles of extended dosing of epoetin alfa in anemic patients who have chronic kidney disease and are not on dialysis

BACKGROUND AND OBJECTIVES

Emerging evidence suggests that epoetin alfa can be administered at extended intervals of up to 4 wk. This open-label, randomized study was performed to characterize the pharmacokinetic and pharmacodynamic profiles of four dosing regimens of epoetin alfa administered subcutaneously in anemic patients who had chronic kidney disease and were not on dialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Thirty-eight patients, enrolled from nine centers in the United States, were > or =18 yr of age and had hemoglobin <11.0 g/dl and GFR 12 to 60 ml/min per 1.73 m(2). Patients received one of four epoetin alfa dosing regimens: 50 IU/kg three times per week, 10,000 IU once weekly, or 20,000 IU every 2 wk for 36 d or 40,000 IU every 4 wk for 64 d. Each regimen provided a similar dosage of epoetin alfa over 4 wk. Dosage adjustments were not permitted.

RESULTS

Drug exposure to epoetin alfa over 4 wk, based on area under the curve, was somewhat higher with the extended interval regimens compared with the three-times-weekly regimen. Mean change in hemoglobin during the study period was similar for all regimens. No patients were transfused. Three patients experienced five serious adverse events, none of which was considered treatment related.

CONCLUSIONS

Extended dosing interval regimens of epoetin alfa yielded modest pharmacokinetic differences but a similar pharmacodynamic response, suggesting that less frequent, higher dosages of epoetin alfa may be as effective as the current three-times-weekly regimen in anemic patients who have chronic kidney disease and are not on dialysis.

The optimal hemoglobin in dialysis patients- a critical review

The introduction of recombinant human erythropoietin treatment has been one of the most important advances in the treatment of dialysis patients and others with chronic kidney disease (CKD). Treatment of CKD anemia has been shown to reduce the need for blood transfusions and to improve quality of life. However, the target hemoglobin level in treating patients is currently controversial. This is because of the recent publication of two randomized controlled studies in nondialysis CKD patients, the CREATE and CHOIR studies, as well as an accompanying meta-analysis. These studies demonstrate increase risk for death and cardiovascular complications when aiming for a hemoglobin (Hgb) level of >12 g/dl. In light of this new data, the National Kidney Foundation Kidney Disease Outcomes Quality Initiative anemia guidelines are being revised. The Food and Drug Administration has issued a Black Box warning and indicated that hemoglobin levels do not exceed 12 g/dl. While observational data suggest a benefit for higher hemoglobin levels, these studies have limitations because of their retrospective design and the potential effect of confounding factors. Hence, reliance on observational studies to guide CKD anemia treatment is a potentially flawed and hazardous process. In this editorial we propose that the current literature does not support an upper Hgb target above 12 g/dl. We also suggest that the current reimbursement system for erythropoiesis stimulating agent treatment potentially encourages unsafe overtreatment.

Does epoetin alfa improve health-related quality of life in chronically ill patients with anemia? Summary of trials of cancer, HIV/AIDS, and chronic kidney disease

OBJECTIVES

Anemia, defined as having low levels of hemoglobin (HGB), is caused by disease-related (e.g., bone marrow suppression, nutritional deficiency) or treatment-related (e.g., chemotherapy, antiretroviral therapy) factors. Although epoetin alfa has been shown to improve HGB outcomes in cancer, HIV/AIDS, and chronic kidney disease (CKD), these results have been viewed in isolation, rather than across populations. The purpose of this article is to review findings from trials that evaluated the impact of epoetin alfa on HGB and health-related quality of life (HRQL) across various populations with different underlying causes of anemia.

METHODS

A review of clinical trials published in English between January 1993 and September 2005. Searches were conducted using MEDLINE and EMBASE. Between- and within-group changes in HGB and HRQL were examined.

RESULTS

One hundred ten articles were retrieved and 18 were reviewed. Statistically significant improvements in HGB were generally seen (1) between groups for cancer patients receiving epoetin alfa compared with those receiving placebo or standard of care (SOC) (between-group differences in changes from baseline to end point ranging from 1.2 to 1.9 g/dl); and (2) within groups for HIV/AIDS and CKD patients receiving epoetin alfa (changes from baseline to end point of 2.5 and 2.9 g/dl and 2.7 g/dl, respectively). Statistically and clinically significant improvements in HRQL, particularly with regard to fatigue, were seen across chronic conditions based on the Linear Analog Scale Assessment energy scale; where improvements of at least 8 mm-considered clinically relevant-were generally seen (1) between groups for cancer patients receiving epoetin alfa compared with those receiving placebo or SOC (differences in changes from baseline to end point from 0.8 to 19.8 mm); and (2) within groups for HIV/AIDS and CKD patients receiving epoetin alfa (changes from baseline to end point of 23 and 25 mm and 28 mm, respectively).

CONCLUSIONS

Results of published clinical trials suggest that treatment of anemia associated with cancer, HIV/AIDS and CKD can have a significant impact on HRQL, particularly fatigue, and that this impact is both statistically and clinically significant.

Validation of single-item linear analog scale assessment of quality of life in neuro-oncology patients

Assessment of patient quality of life (QOL) requires balancing the details provided by multi-item assessments with the reduced burden of single-item assessments. In this project, we investigated the psychometric properties of single-item Linear Analog Scale Assessments (LASAs) for patients with newly diagnosed high-grade gliomas. Measures included QOL LASAs (overall, physical, emotional, spiritual, intellectual), Symptom Distress Scale (SDS), Profile of Mood States (POMS; overall, confusion, fatigue), and Functional Assessment of Cancer Therapy-Brain (FACT-Br; overall, brain, physical, emotional). Associations of LASA measures with SDS, POMS, and FACT-Br domains and with Eastern Cooperative Oncology Group performance score (PS) and Mini-Mental State Examination (MMSE) were assessed. Repeated measures ANOVA models compared the change over time of LASAs and SDS, POMS, and FACT-Br. Two hundred five patients completed the assessments across three time points. To allow comparison across measures, all scores were converted to a scale of 0-100, with higher scores indicating better QOL. LASA mean scores ranged from 60 to 78; SDS, POMS, and FACT-Br ranged from 62 to 81. FACT-Br physical (P<0.001) and POMS fatigue subscale (P=0.005) decreased over time, as did LASA physical (P=0.08). LASA scales were strongly associated with corresponding scales on SDS, POMS, and FACT-Br (0.44<rho<0.65; P<0.001). LASA was negatively associated with PS and positively with MMSE, with associations similar in magnitude to the other QOL and psychosocial measures. The data suggest that the single-item LASA scales are valid for assessing QOL of cancer patients and are an appropriate alternative when a shorter instrument is warranted.

Use of erythropoiesis-stimulating agents in patients with anemia of chronic kidney disease: overcoming the pharmacological and pharmacoeconomic limitations of existing therapies

Stage 3 chronic kidney disease (CKD), which is characterized by a glomerular filtration rate of 30 to 60 mL/min/1.73 m2 (reference range, 90-200 mL/min/1.73m2 for a 20-year-old, with a decrease of 4 mL/min per decade), affects approximately 8 million people in the United States. Anemia is common in patients with stage 3 CKD and, if not corrected, contributes to a poor quality of life. Erythropoiesis-stimulating agents (ESAs), introduced almost 2 decades ago, have replaced transfusions as first-line therapy for anemia. This review summarizes the current understanding of the role of ESAs in the primary care of patients with anemia of CKD and discusses pharmacological and pharmacoeconomic issues raised by recent data. Relevant studies in the English language were identified by searching the MEDLINE database (1987-2006). Two ESAs are currently available in the United States, epoetin alfa and darbepoetin alfa. More frequent dosing with epoetin alfa is recommended by the labeled administration guidelines because it has a shorter half-life than darbepoetin alfa. Clinical experience also supports extended dosing intervals for both these ESAs. Use of ESAs in the management of anemia of CKD is associated with improved quality of life, increased survival, and decreased progression of renal failure. Some evidence suggests that ESAs have a cardioprotective effect. However, correction of anemia to hemoglobin levels greater than 12 g/dL (to convert to g/L, multiply by 10) appears to increase the risk of adverse cardiac outcomes and progression of kidney disease in some patients. The prescription of ESAs in the primary care setting requires an understanding of the accepted use of these agents, the associated pharmacoeconomic challenges, and the potential risks. This review considers the need to balance effective ESA dosing intervals against the potential risks of treatment.

Dose and cost comparison of erythropoietic agents in the inpatient hospital setting

PURPOSE

The inpatient dosing patterns and treatment costs in cancer and predialysis chronic kidney disease (CKD) patients treated with erythropoietic agents from a hospital pharmacy perspective were studied.

METHODS

An analysis of electronic inpatient records from the Premier Perspective comparative hospital database was conducted. Study participants were identified through hospitalizations recorded between July 2002 and March 2005 from over 500 hospitals nationwide. Adult patients with an admitting diagnosis of cancer or predialysis CKD and treated with epoetin alfa or darbepoetin alfa during hospitalization were included. Patients who had received renal dialysis or both agents during a hospitalization were excluded. Wholesale acquisition costs from September 2006 were used to calculate drug costs.

RESULTS

A total of 25,645 hospitalized patients with cancer (22,873 received epoetin alfa; 2,772 received darbepoetin alfa) and 66,822 hospitalized patients with CKD (60,079 received epoetin alfa; 6,743 received darbepoetin alfa) were identified. The mean cumulative dose per hospitalization resulted in dose ratios of 245:1 and 242:1 (units epoetin alfa:micrograms darbepoetin alfa) for cancer and CKD patients, respectively. On the basis of the cumulative dose per hospitalization, drug costs for darbepoetin alfa-treated patients were approximately 50% higher than drug costs for epoetin alfa-treated patients for both oncology and CKD patients.

CONCLUSION

Epoetin alfa was associated with less cost compared with darbepoetin alfa for treating inpatients with cancer or CKD. Further research including the patients' clinical outcomes is necessary to determine the true pharmacoeconomic differences between the two agents.

Prevalence, etiology, and consequences of anemia and clinical and economic benefits of anemia correction in patients with chronic kidney disease: an overview

PURPOSE

The prevalence of chronic kidney disease (CKD) and anemia in the United States, classification scheme for CKD, definition of anemia, etiology and consequences of anemia in patients with CKD, and the clinical and economic benefits of correcting anemia are described.

SUMMARY

Approximately 20 million people in the United States population have CKD, and 2-4 million of these may also have anemia, which often goes undetected and untreated. Patients with CKD are now classified into five stages based on the degree of kidney function impairment. Here, anemia is caused by insufficient erythropoietin production, and may occur as early as stage 3 CKD. Potential consequences of anemia include cognitive impairment, angina, and the cardiorenal anemia syndrome, a triad of worsening anemia, worsening CKD, and worsening congestive heart failure. Treatment of anemia in predialysis patients with stage 2-4 CKD may slow renal disease progression and improve energy, work capacity, health-related quality of life, and cardiac function. Optimizing the hemoglobin or hematocrit value before initiating dialysis may reduce mortality. Anemia contributes to significant healthcare costs associated with CKD. Substitution of the subcutaneous route of administration for the intravenous route of administration for epoetin alfa can reduce drug acquisition and healthcare costs, the two largest components of healthcare costs in CKD patients. Efforts to slow the progression of CKD could also have a substantial impact on hospitalizations and costs.

CONCLUSION

Correcting anemia has the potential to improve clinical and economic outcomes in patients with CKD.

Dosing patterns, hematologic outcomes, and costs of erythropoietic agents in anemic predialysis chronic kidney disease patients from an observational study

INTRODUCTION

Epoetin alfa (EPO) and darbepoetin alfa (DARB) are two erythropoietic agents currently available in the United States for the treatment of anemia in patients with pre-dialysis chronic kidney disease (CKD). The goal of this study was to assess and compare EPO- and DARB-treated CKD patients with respect to dosing patterns, hematologic outcomes, and associated costs.

MATERIALS AND METHODS

In this multicenter, retrospective chart review, 400 charts of anemic predialysis CKD patients (200 treated with EPO and 200 treated with DARB) were sequentially selected from a large self-insured employer health insurance database. The database included both employees and their dependents. Selection criteria included patients newly initiated on EPO or DARB between July 2002 and December 2003 who had at least 24 weeks of dosing and hematologic laboratory data available. Patients with a diagnosis of malignancy or on dialysis were excluded. Dosing frequency was categorized as once weekly (QW), once every 2 weeks (Q2W), every 3 weeks (Q3W), or every 4 weeks (Q4W). Hemoglobin (Hb) levels and dates/doses of EPO and DARB administrations were recorded. Costs were calculated using 2005 wholesale acquisition costs.

RESULTS

Baseline demographics were similar in the EPO and DARB groups with respect to race, sex, renal function, and Hb. Extended dosing (defined as > or =Q2W) was common in both groups. The predominant dosing frequency was Q2W (59.5% of patients) for EPO and Q3W (68.0% of patients) for DARB. Hematologic response (defined as Hb > or = 11 g/dL) was significantly greater in the EPO group at early time points (week 4: EPO 28%, DARB 12%; week 8: EPO 39%, DARB 21%; week 12: EPO 98%, DARB 89%). In both groups, 99% of patients achieved hematologic response by week 24. The mean cumulative dose during the first 12 weeks (initiation phase) was EPO 141,481 +/- 32,426 units and DARB 499 +/- 152 microg. The 24 week mean cumulative dose (initiation and maintenance phase) was EPO 243,715 +/- 39,264 units and DARB 902 +/- 265 microg, corresponding to a drug cost of EPO $2,966 and DARB $3,933 and a dose ratio of 270:1 (units EPO:microg DARB).

CONCLUSION

Extended dosing frequency (> or = Q2W) was common in both groups. EPO treatment was associated with a significantly greater hematologic response at early time points (weeks 4, 8, and 12). Erythropoietic agent cost was 33% higher in the DARB group.

Hemoglobin Maintenance with use of Extended Dosing of Epoetin Alfa in Patients with Diabetes and Anemia of Chronic Kidney Disease

OBJECTIVE

To compare the efficacy of extended epoetin alfa dosing in maintaining hemoglobin (Hb) concentrations in patients with and without diabetes as the primary cause of chronic kidney disease.

METHODS

We undertook a post hoc analysis of the Clinical Evaluation of PROCRIT(R) for Maintenance Phase Treatment of Patients With Anemia Due to Chronic Kidney Disease (PROMPT) study. The study patients had chronic kidney disease but were not receiving dialysis, had stable Hb levels of >or= 11.0 g/dL, and had been receiving epoetin alfa for >or= 2 months. Patients received 1 of 4 epoetin alfa dosing regimens administered subcutaneously for up to 16 weeks: 10,000 U once weekly (QW), 20,000 U every 2 weeks (Q2W), 30,000 U every 3 weeks (Q3W), or 40,000 U every 4 weeks (Q4W). The primary end point was the percentage of patients able to achieve Hb maintenance, defined as a mean Hb level of >or= 11.0 g/dL from week 2 to final measurement.

RESULTS

Among 445 evaluable patients, 201 had diabetes and 244 did not have diabetes. Mean baseline Hb was 11.9 g/dL in both groups. The percentage of patients achieving Hb maintenance, stratified by epoetin alfa dosing regimen, was similar in patients with and those without diabetes: QW (90.2% versus 96.5%), Q2W (91.1% versus 87.9%), Q3W (80.0% versus 75.7%), or Q4W (79.2% versus 72.5%). The incidence of adverse events was low and comparable between patients with and those without diabetes.

CONCLUSION

Approximately 90% of patients with and without diabetes in the QW and Q2W groups and more than 70% in the Q3W and Q4W groups maintained mean Hb levels of >or= 11.0 g/dL from week 2 to final measurement. These results demonstrated that patients with diabetes responded in a similar manner as patients without diabetes to extended dosing of epoetin alfa up to Q4W.

The economic impact of epoetin alfa therapy on delaying time to dialysis in elderly patients with chronic kidney disease

The aim of this study was to evaluate the impact of epoetin alfa (EPO) therapy on delaying progression to renal dialysis and quantify the associated medical cost savings in elderly chronic kidney disease (CKD) patients. Elderly (>/=65 years) dialysis patients who had >/=1 hemoglobin (Hb) value and >/=1 glomerular filtration rate (GFR) value of <60 mL/min/1.73 m(2) were identified using health claims and laboratory data from the period January 1999 to February 2005. Exclusion criteria included: organ transplantation, blood transfusion, use of darbepoetin alfa, and dialysis for reasons other than CKD. Each EPO patient was matched by Hb and GFR to one control patient. The time from when matched patients had the same GFR value to dialysis was compared. The economic impact of EPO on delaying dialysis was monetized using standardized health plan payments, and adjusted to 2005 United States dollars. Sixty-eight patients (34 EPO and 34 matched controls) formed the study population. The average time to dialysis was 156 days longer for the EPO group compared to the matched control group (p = 0.003). Analysis by CKD severity revealed that EPO therapy in less severe CKD patients offered a greater delay in time to dialysis (Stage 4: 213 days difference, p = 0.003; Stage 5: 104 days difference, p = 0.160). EPO treatment resulted in cost savings of $43,374-$59,222 per patient compared to non-EPO matched controls. This retrospective matched cohort study suggests that EPO therapy has a beneficial impact on delaying progression to dialysis in elderly CKD patients, especially in those with less severe CKD.

Epoetin alfa once every 2 weeks is effective for initiation of treatment of anemia of chronic kidney disease

There are limited data suggesting that initiation of epoetin alfa at extended dosing intervals of every 2, 3, or 4 wk may be efficacious for treating anemia in patients who have chronic kidney disease and are not on dialysis (CKD-NOD). This open-label, multicenter, single-arm study investigated the efficacy of administration of 20,000 IU of epoetin alfa once every 2 wk as initiation therapy in these patients. Adults with CKD-NOD were eligible when they had hemoglobin (Hb) <11 g/dl, GFR of 10 to 60 ml/min per 1.73 m2, and stable serum creatinine for the past 6 mo. Patients received 20,000 IU of epoetin alfa subcutaneously every 2 wk for up to 27 wk, with dosage adjustments permitted after 4 wk of treatment. The primary efficacy end point was the proportion of patients with Hb response, defined as achievement of the target Hb range of 11 to 12 g/dl for at least two consecutive visits. Sixty-seven patients were enrolled; >88% (59 of 67) of patients achieved an Hb response. Mean Hb increased to the targeted range by week 6 and remained in the range through week 28. Hb increases of 1 and 2 g/dl were observed in 91 and 78% of patients, respectively. Epoetin Alfa was well tolerated; most adverse events were mild or moderate in nature and typical of the CKD patient population. In this study, results demonstrated that epoetin alfa can be initiated safely and effectively at an extended dosing interval of 20,000 IU every 2 wk in patients with CKD-NOD.

The relative dosing of epoetin alfa and darbepoetin alfa in chronic kidney disease

OBJECTIVE

The purpose of this study was to review and analyze current research to evaluate the dose ratio of epoetin alfa and darbepoetin alfa for the treatment of anemia in chronic kidney disease (CKD) and to identify determinants of the variation in epoetin alfa:darbepoetin alfa dose ratios across studies.

METHODS

A systematic review of the literature for comparative switch and non-switch studies of epoetin alfa and darbepoetin alfa treatments in CKD for the period 2000-2005 was performed. Two reviewers independently assessed the quality of the information. Data on the study design and outcomes were collected for each selected study. The dose ratio from epoetin alfa to darbepoetin alfa was calculated for each study, and the results were reported stratified by study characteristics. To control for differences in study design and characteristics that could explain the variability in the relative dosages of the two agents across studies, multivariate regression analysis was conducted. Based on these results, a dose conversion ratio for Canada was estimated.

RESULTS

A total of 21 studies involving 16 378 patients exposed to epoetin alfa or darbepoetin alfa in CKD were identified. Univariate analysis of the dose ratios indicated a mean dose ratio of 217:1 (IU of epoetin alfa:mug of darbepoetin alfa). Results from the multivariate analysis demonstrated that the study design (i.e., switch study versus straight comparison studies) and geographical coverage (i.e., United States) affected the results. Based on the multivariate analysis, the dose conversion ratio between epoetin alfa and darbepoetin alfa for Canada was 169:1.

CONCLUSIONS

Despite limitations associated with switching studies and the limited total number of studies available, this systematic review based on aggregated results provides further evidence to the clinical community that the dose conversion ratio for epoetin alfa:darbepoetin alfa in CKD patients in Canada is approximately 169:1. At that ratio, treatment with epoetin alfa is 11-18% cheaper than treatment with darbepoetin alfa in Canada.

Medical Costs of Untreated Anemia in Elderly Patients with Predialysis Chronic Kidney Disease

The objective of this study was to quantify the incremental medical costs that are associated with untreated anemia among elderly patients with predialysis chronic kidney disease (CKD). An analysis of claims and laboratory data between January 1999 and February 2005 was conducted. Inclusion criteria were age >/=65 yr, two or more hemoglobin readings, one or more claims for CKD, and two or more GFR values of <60 ml/min per 1.73 m(2) (stages 3 to 5 CKD). Patients were excluded when they had cancer or lupus, had received organ transplantation, or were treated for anemia. An open-cohort design was used to classify patients' observation periods into anemia and nonanemia. Both univariate and multivariate analyses were conducted to compare periods of anemia and nonanemia for average monthly medical costs; the latter was adjusted for age, gender, GFR, diabetes, hypertension, liver cirrhosis, coronary artery disease, myocardial infarction, and left ventricular hypertrophy. A subset analysis of patients with moderate CKD (stage 3) was conducted. A total of 2001 patients were identified. Untreated anemia was associated with a significant increase in medical costs, with an unadjusted incremental monthly cost of $1089 (P < 0.0001) and a cost ratio of 1.8:1 relative to nonanemia. After controlling for covariates, untreated anemia remained significantly associated with a cost increase (adjusted incremental monthly cost $503; cost ratio 1.4:1; P < 0.0001). Similar significant cost burden was observed in the subset of patients with moderate CKD. The retrospective observational design may be more susceptible to bias than a randomized, controlled trial. This large study, which was based on real-life practice data, demonstrated that untreated anemia in elderly patients with predialysis CKD was associated with a significant increase in medical costs.

Relationship between hemoglobin level and quality of life in anemic patients with chronic kidney disease receiving epoetin alfa

OBJECTIVES

To evaluate the relationship between hemoglobin (Hb) level and quality of life (QOL) in anemic patients with non-dialysis chronic kidney disease receiving epoetin alfa.

PATIENTS AND METHODS

A post-hoc analysis using data from a multicenter, open-label, prospective study of epoetin alfa for anemia in patients with chronic kidney disease not on dialysis was conducted. The relationship between Hb and QOL was analyzed using correlation and longitudinal analyses, the latter adjusting for sample selection bias. The Linear Analog Scale Assessment (LASA) and the Kidney Disease Questionnaire (KDQ) subscales were used to measure QOL. The impact of an incremental 1 g/dL increase in Hb level on LASA and KDQ scores was determined using an incremental analysis.

RESULTS

A total of 1183 and 1044 patients formed the study populations for the LASA and KDQ analyses, respectively. There was a positive and significant relationship between Hb levels and QOL (p < 0.05). Using non-linear regression analysis, we characterized the sigmoid-shape of the relationship between Hb levels and QOL scores. Hemoglobin change was a statistically significant determinant of QOL improvement for both LASA and KDQ scales (p < 0.05). The model predicted that, based on a 2 unit change in Hb, the greatest incremental QOL improvement per unit of Hb increase occurred when Hb was in the range of 11 to 12 g/dL.

CONCLUSIONS

This study demonstrates that, beyond the well-known relationship between Hb increases and QOL improvements, the maximal incremental gain in QOL occurred when Hb reached 11 to 12 g/dL. This suggests that treating anemic patients with non-dialysis chronic kidney disease until their Hb level reaches 12 g/dL will result in the greatest QOL improvement per Hb unit increase. The analyses were conducted based on an open-label study of epoetin alfa and could be further validated using a randomized, controlled trial, comparing incremental gains in QOL associated with treatment initiation at varying levels of Hb across arms.

Prevalence and treatment of anemia with once-weekly epoetin alfa in patients with diabetes and chronic kidney disease

OBJECTIVE

To describe the characteristics and prevalence of anemia in patients with diabetes and chronic kidney disease (CKD) not receiving dialysis and to evaluate the efficacy and safety of once-weekly (QW) epoetin alfa for the treatment of anemia in these patients.

METHODS

Post hoc subset analyses were conducted for 2 studies: a prospective, multicenter survey evaluating the prevalence of anemia in patients with CKD (the Prevalence of Anemia in Early Renal Insufficiency [PAERI] study) and a prospective, multicenter, open-label trial evaluating the efficacy and safety of QW epoetin alfa for the treatment of anemia associated with CKD (the Clinical Evaluation of Procrit Dosed Once Weekly in Patients With Anemia Due to Early Renal Insufficiency [POWER] study). Patients in the POWER study received epoetin alfa, 10,000 U subcutaneously QW for up to 16 weeks. Each study subset consisted of patients with type 1 or type 2 diabetes.

RESULTS

More than 60% of patients in both studies had diabetes. In the PAERI study, 52.4% of the patients with diabetes (N = 3,361) had a hemoglobin (Hb) level < or = 12 g/dL, and 10.5% had Hb < or = 10 g/dL. Female sex, African American race, reduced kidney function, reduced transferrin saturation, and diabetes as the cause of CKD were strongly associated with anemia. In the POWER study, the mean Hb level in the patients with diabetes (N = 816) increased from 9.1 g/dL (baseline) to 11.6 g/dL (final); the mean increase in Hb from baseline was 2.4 g/dL (P<0.0001). Epoetin alfa therapy was associated with significant quality of life improvements and was well tolerated.

CONCLUSION

Diabetes is prevalent in patients with CKD not receiving dialysis, and anemia is prevalent among these patients. Epoetin alfa QW is safe and effective in treating anemia in these patients.

Dosing patterns, hematologic outcomes, and costs of erythropoietic agents in predialysis chronic kidney disease patients with anemia

OBJECTIVE

Few observational studies have evaluated the use of epoetin alfa (EPO) and darbepoetin alfa (DARB) in chronic kidney disease (CKD) patients with anemia. The objective of this study was to investigate dosing patterns, hematologic outcomes, and intervention costs with EPO and DARB in anemic CKD patients treated in an ambulatory care setting.

METHODS

This was a multicenter, retrospective, chart review of predialysis CKD patients with anemia treated with EPO or DARB. Charts were sequentially selected from 435 EPO and 432 DARB patients naive to erythropoietic therapy and treated for > or = 24 weeks. Hemoglobin (Hb) levels, dates, and EPO/DARB doses were recorded. Drug costs using 2005 wholesale acquisition costs (WAC) and Federal Supply Schedule (FSS) pricing were based on the mean cumulative drug dose over the 24-week study period.

RESULTS

A total of 393 EPO and 396 DARB charts met all criteria with predominantly male subjects (EPO: 94%; DARB: 96%). Mean baseline GFR and Hb levels were similar. Once-weekly and extended dosing (> or = Q2W) was common in both groups. At Weeks 4, 8, and 12 following initiation of therapy, a greater proportion of EPO than DARB patients reached target Hb levels (> or = 11 g/dL) (p < 0.0001); at Week 24, all patients reached target Hb levels. Mean 24-week cumulative doses were EPO 279 336 +/- 68 302 units and DARB 1084 +/- 246 microg. Drug cost was higher for DARB independent of pricing utilized (WAC: EPO = 3400 US dollars, DARB = 4726 US dollars; FSS: EPO = 1528 US dollars, DARB = 2379 US dollars).

CONCLUSIONS

Extended dosing (Q2W) was common in EPO- and DARB-treated patients with CKD-related anemia, with EPO-treated patients experiencing a significantly greater hematologic response (at Weeks 4, 8, and 12). In addition, drug cost was 39-56% higher in the DARB group. The male predominance may limit generalizability, warranting further research in other populations.

Darbepoetin alfa administered every other week maintains hemoglobin levels over 52 weeks in patients with chronic kidney disease converting from once-weekly recombinant human erythropoietin: results from simplify the treatment of anemia with Aranesp (STAAR)

BACKGROUND/AIM

Darbepoetin alfa, an effective treatment for anemia of chronic kidney disease (CKD), can be administered at extended intervals. Simplify the Treatment of Anemia with Aranesp (STAAR), a multicenter, 52-week study, was conducted to assess the efficacy of darbepoetin alfa administered subcutaneously every other week (Q2W) in maintaining hemoglobin (Hb) in CKD patients not receiving dialysis.

METHODS

This is a subgroup analysis of subjects converted from once-weekly (QW) recombinant human erythropoietin (rHuEPO; US Aranesp package insert) and who received up to 52 weeks of darbepoetin alfa therapy (evaluation period 20-32 weeks). Enrolled subjects had a creatinine clearance < or = 70 ml/min or an estimated glomerular filtration rate < or = 60 ml/min and transferrin saturation > or = 20%. Darbepoetin alfa doses were titrated to maintain Hb levels < or = 12 g/dl. The primary endpoint was mean Hb during evaluation.

RESULTS

There were 524 subjects enrolled in the study who were previously receiving rHuEPO QW. Mean Hb +/- standard deviation was 11.2 +/- 1.27 g/dl at baseline, and the least squares mean +/- SE was 11.4 +/- 0.04 during evaluation. The mean +/- SD Q2W darbepoetin alfa dose was 49.7 +/- 21.9 microg at baseline and 48.9 +/- 35.5 microg at evaluation. Darbepoetin alfa was well tolerated.

CONCLUSIONS

Study subjects with CKD receiving QW rHuEPO were effectively converted to Q2W darbepoetin alfa, which was well tolerated. Hb levels were maintained over 52 weeks without a significant change in darbepoetin alfa dose.

Racial variations in erythropoietic response to epoetin alfa in chronic kidney disease and the impact of smoking

BACKGROUND

Of the known risk factors for chronic kidney disease (CKD), race represents one that is non-modifiable, while smoking is another that is modifiable. Moreover, smoking tends to increase red blood cell mass, which is frequently diminished in CKD. No studies have examined the interplay of race with smoking on anaemia management in patients with CKD.

METHODS

We examined the effects of smoking on anaemia management in CKD and its variation across race in a previously conducted study of CKD patients (n = 1312) initiated on weekly epoetin alfa and followed for 16 weeks. Smoking status was classified as current vs non-smoker. Race was classified as African-American vs non-African-American. Changes in estimated glomerular filtration rate, urinary albumin excretion, and erythropoietic response to weekly epoetin alfa were examined.

RESULTS

Overall, African-Americans had lower baseline Hb than non-African-Americans. African-American non-smokers did not mount an erythropoetic response comparable to other non-smokers by final Hb (mean 11.29 g/dl vs 11.64 g/dl, P<0.001) or week 16 Hb (mean 11.61 g/dl vs 11.86 g/dl, P = 0.02). However, African-American smokers had a more significant erythropoietic response than their non-smoking counterparts and were comparable to their smoking non-African-American counterparts. There was no effect of smoking on renal function or urinary protein excretion over the course of the study.

CONCLUSION

African-American non-smokers exhibit a diminished response to standard epoetin alfa dosing than non-smokers in other races. However, African-American smokers with CKD exhibit a response to epoetin alfa comparable to patients of other races. These findings may have implications for African-Americans who have CKD-related anaemia.

Chronic Kidney Disease: A Risk Factor for Cardiovascular Disease

The goal of risk stratification of CVD inpatients with CKD is to lead to effective and early intervention and to prevent the adverse outcomes associated with this complex multisystem disease that is characteristic of growing number of patients with CKD in the general population and of patients receiving dialysis therapy or kidney transplantation. By 2030, there will be 2.24 million patients with ESRD in the United States, and approximately 1.3 million of these cases of ESRD will be caused by diabetes mellitus. Thus, CVD in this high-risk population presents a challenge for the nephrology and the cardiology community.

Extended epoetin alfa dosing in chronic kidney disease patients: a retrospective review

BACKGROUND

The effectiveness of extended dosing of epoetin alfa beyond once-weekly (QW) has not been well explored in patients being treated for anaemia of chronic kidney disease (CKD). The current study was undertaken to assess the effectiveness of extended dosing in maintaining haemoglobin (Hb) levels in this population.

METHODS

A retrospective chart review was conducted to assess the efficacy of extended epoetin alfa dosing in patients being treated for CKD-related anaemia. Eligible patients were to have received epoetin alfa once every 2 weeks (Q2W), 3 weeks (Q3W), 4 weeks (Q4W), or >Q4W administered subcutaneously for at least 3 months to maintain Hb > or = 11.0 g/dl. Patients were > or =18 years with serum creatinine 1.5 to 6.0 mg/dl for females and 2.0 to 6.0 mg/dl for males, and were not receiving renal replacement therapy. Epoetin alfa dose and dosing frequency were adjusted during treatment at the clinician's discretion. For analysis, patients were stratified into dosing groups based on their most dominant dosing regimen.

RESULTS

243 patients (mean age, 71.5 years; 79% white, 54% female) who received extended epoetin alfa dosing for a mean of 10.3 months were eligible for analysis. Mean baseline estimated glomerular filtration rate and mean serum creatinine were 21.2 ml/min/1.73 m(2) and 3.1 mg/dl, respectively. Primary causes of CKD included hypertension (36%) and diabetes (28%). Most patients (82%) receiving an extended epoetin alfa regimen maintained Hb > or =11.0 g/dl. The most common dosing regimen was Q2W (51%). Mean Hb for each dosing group was maintained between 11.6 g/dl and 12.4 g/dl during the study, and glomerular filtration rate remained stable. Epoetin alfa was well tolerated across all groups.

CONCLUSIONS

Data from private community nephrology practices showed that extended epoetin alfa dosing effectively maintained Hb > or =11.0 g/dl in 82% of these selected patients being treated for anaemia of CKD.