Erythropoietin dose requirements when converting from subcutaneous to intravenous administration among patients on hemodialysis

Subcutaneous Anti-inflammatory Therapies to Prevent Burn Progression in a Swine Model of Contact Burn Injury

INTRODUCTION

If left untreated, burn injuries can deepen or progress in depth within the first 72 hours after injury as a result of increased wound inflammation, subsequently worsening healing outcomes. This can be especially detrimental to warfighters who are constrained to resource-limited environments with delayed evacuation times to higher roles of care and more effective treatment. Preventing this burn progression at the point of injury has the potential to improve healing outcomes but requires a field-deployable therapy and delivery system. Subcutaneous therapies known to treat inflammation delivered local to the wound site may prove to be one such avenue for success.

MATERIALS AND METHODS

Seven Yorkshire-cross swine received partial-thickness burn injuries using a previously established contact burn model. Each animal received one of the seven therapies: (1) saline, (2) heparin, (3) ibuprofen, (4) erythropoietin, (5) resolvin, (6) rapamycin, and (7) placental extract, all of which are either currently employed or are experimental in field use and indicated to treat inflammation. Treatments were delivered subcutaneously on the day of injury and 24 hours post-injury to simulate a prolonged field care scenario, before potential evacuation. Animals and wound development were observed for 28 days before euthanasia. Throughout the course of the study, wounds were observed macroscopically via non-invasive imaging. Histological analyses provided the critical metric of burn progression. Treatment success criteria were designated as the ability to prevent burn progression past 80% of the dermal depth in two of the three treated wounds, a clinically relevant metric of burn progression.

RESULTS

It was determined that the applied model successfully created reproducible partial-thickness burn injuries in this porcine study. No significant differences with regard to lateral wound size or the rate of lateral wound closure were observed in any treatments. Several treatments including resolvin, rapamycin, ibuprofen, and erythropoietin successfully reduced burn progression to less than 80% of the dermal depth in two of the three wounds, 24 hours after injury.

CONCLUSIONS

This report employs an established model of porcine contact burn injury in order to test the ability of local subcutaneous delivery of therapeutics to prevent burn progression at the point of injury, via what is believed to be the inhibition of inflammation. Several treatments successfully prevented burn progression to a full-thickness injury, potentially improving wound healing outcomes in a simulated battlefield scenario. Subcutaneously administered therapies combating burn-induced inflammation at the point of injury may serve as a field-deployable treatment modality to improve warfighter recovery and return to duty.

Erythropoietin Administration for Anemia Due to Chronic Kidney Disease - Subcutaneous OR Intravenous, What Do We Know So Far?

The prevalence of anemia in chronic kidney disease (CKD) patients is almost twice that of the normal population and its severity increases exponentially as the disease worsens, dramatically affecting the quality of an individual’s life. The advent of erythropoiesis stimulating agents (ESA) in the 1980s saw a revolutionary change in the treatment of anemia in CKD patients, drastically improving quality of life (QoL), overall health and reducing the need for blood transfusions. Numerous ESAs have been developed ever since and are in current use, with the primary routes of administration being intravenous (IV) and subcutaneous (SC) injections. Their use, however, has stirred significant controversy over the last two decades. Additionally, despite numerous studies and trials, the latest international recommendations for their use do not provide clear cut guidance with well-grounded evidence on the recommended route of administration for different sets of patients. Instead, this decision has mainly been left up to the physician’s discretion, whilst keeping certain key factors in mind. This review shall summarize, discuss and compare the findings of previous studies on various factors governing the two aforementioned routes of administration and identify areas that need further exploration.

Economic Benefits of Switching From Intravenous to Subcutaneous Epoetin Alfa for the Management of Anemia in Hemodialysis Patients

Background:

Erythropoiesis-stimulating agents including epoetin alfa have been a mainstay of anemia management in patients with chronic kidney disease. Although the standard practice has been to administer epoetin alfa to patients on hemodialysis (HD) intravenously (IV), subcutaneous (SQ) epoetin alfa is longer acting and achieve the same target hemoglobin level to be maintained at a reduced dose and cost.

Objective:

The primary objective of this study was to determine the economic benefits of change in route of epoetin alfa administration from IV to SQ in HD patients. The secondary objectives were (1) to determine the differences in epoetin alfa doses at the pre-switch (IV) and post-switch period (SQ) and (2) to determine serum hemoglobin concentration, transferrin saturation, ferritin level, IV iron dose and cost in relationship to route of epoetin alfa administration.

Design:

This retrospective observational study included patients who transitioned from IV to SQ epoetin alfa.

Setting:

Two HD sites in southern Saskatchewan (Regina General Hospital, and Wascana Dialysis Unit, Regina) and 2 sites in northern Saskatchewan (St. Paul’s [SPH] Hospital, and SPH Community Renal Health Center, Saskatoon).

Patients:

The study includes 215 patients who transitioned from IV to SQ and were alive at the end of 12-month follow-up period.

Measurements:

We calculated the dose and cost of different routes of epoetin alfa administration/patient month. Also, serum hemoglobin, markers of iron stores (transferrin saturation and ferritin), IV iron dose, and cost were determined in relation to route of epoetin alfa administration.

Methods:

Data were gathered from 6 months prior (IV) to 12 months after switching treatment to SQ. The paired t-test and Wilcoxon signed-rank test were used to compare variables between pre-switch (IV) and post-switch (SQ) period.

Results:

The median cost (interquartile range) of epoetin alfa/patient-month decreased from (CAD508.3 [CAD349-CAD900.8]) pre-switch (IV) to (CAD381.2 [CAD247-CAD681]) post-switch (SQ) (P < .001), a decrease of 25%. The median epoetin alfa dose/patient-month reduced from (38 500 [25 714.3-64 166.5] international unit) pre-switch to (26 750.3 [17 362.6-48 066] IU) post-switch (P < .001), a decrease of 30.51%. The mean hemoglobin concentration (± standard deviation) for patients in both periods remained stable (103.3 ± 9.2 vs 104.3 ± 13.3 g/L, P = .34) and within the target range. There were no significant differences in transferrin saturation, ferritin, and IV iron dose and cost between the 2 study periods.

Limitations:

We were unable to consistently obtain information across all the sites on hospitalizations, inflammatory markers, nutritional status, and gastrointestinal bleeding. In addition, as our study sample was subject to survival bias, we cannot generalize our study results to other populations.

Conclusions:

We have shown that administering epoetin alfa SQ in HD patients led to a 30.51% reduction in dose and 25% reduction in cost while achieving equivalent hemoglobin levels. Given the cost sparing advantages without compromising care while achieving comparable hemoglobin levels, HD units should consider converting to SQ mode of administration.

Trial registration:

The study was not registered on a publicly accessible registry as it was a retrospective chart review and exempted from review by the Research Ethics Board of the former Regina Qu’Appelle Health Region.

Glomerular Filtration Rate and Initiation of Dialysis

The proportion of patients with advanced chronic kidney disease (CKD) initiating dialysis at higher glomerular filtration rate (GFR) has increased over the past decade. Recent data suggest that it may be associated with increased mortality. The goal of this analysis was to compare survival outcomes in patients with early and late start dialysis. We performed a retrospective analysis of hemodialysis (HD) incident patients from 1 January 2010 to 30 September 2014. Patients were classified into two groups by estimated GFR at dialysis initiation (eGFR ≥10: early start and <10 mL/min per 1.73m² : late start). Logistic regression was used to evaluate factors associated with early and late dialysis start, and Kaplan-Meier graphs and Cox regression models in survival analysis. In this total incident population (N = 235), 42 patients had an early dialysis start. Compared with the group with an eGFR of <10 mL/min per 1.73 m² at dialysis start, a Cox model showed an incremental increase in mortality associated with earlier dialysis start (P = 0.027). Independent factors (P < 0.05) associated with mortality in the multivariable Cox model in early dialysis start were: hypertension (HR 9.32, CI: 1.34-17.87), diabetes (HR 1.8, CI: 0.4-13.2) and albumin <3.5 g/dL (HR 1.5, CI: 0.8-6.2). Older patients (HR 0.084, CI: 0.008-0.863) with low phosphorus levels (HR 0.02, CI: 0.0-0.527) also had statistically significant results, although they showed a reduced risk of mortality. Early dialysis initiation was associated with an increased mortality risk, arguing against aggressive early dialysis initiation based primarily on eGFR alone.

Administration of the same dose of epoetin-beta intravenously and subcutaneously to patients with renal anaemia

OBJECTIVE

Subcutaneous (s.c.) administration of erythropoietin (EPO) is recommended over the intravenous (i.v.) route to reduce doses and costs. Optimal iron treatment is important for the optimal EPO effect. This study investigated whether the haemoglobin (Hb) level of a single patient could be preserved with the same dose of EPO given i.v. as given s.c.

MATERIAL AND METHODS

One-hundred and forty-five haemodialysis patients with the same weekly EPO dose s.c. for 3 months and a stable Hb (maximum fluctuation of 1 mmol/l) were randomized in a crossover study to group A (4 months i.v. then 4 months s.c. EPO) or group B (4 months s.c. then 4 months i.v. EPO, with unchanged EPO dose). Ferritin had to be 300-800 μg/l or transferrin saturation ≥ 20%. Patients with a fall in Hb >1 mmol/l were withdrawn.

RESULTS

Ferritin and transferrin saturation remained within the target range, and mean Hb in the range of 1 mmol/l. Mean EPO doses were unchanged in both groups, and no difference was found between the dropouts due to Hb fall >1 mmol/l in the i.v. and s.c. groups during the first period of the trial.

CONCLUSION

In iron-replete haemodialysis patients the same EPO dose given intravenously is just as effective as given subcutaneously.

Timing of dialysis initiation and survival in ESRD

BACKGROUND AND OBJECTIVES

The optimal time of dialysis initiation is unclear. The goal of this analysis was to compare survival outcomes in patients with early and late start dialysis as measured by kidney function at dialysis initiation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed a retrospective analysis of patients entering the U.S. Renal Data System database from January 1, 1995 to September 30, 2006. Patients were classified into groups by estimated GFR (eGFR) at dialysis initiation.

RESULTS

In this total incident population (n = 896,546), 99,231 patients had an early dialysis start (eGFR >15 ml/min per 1.73 m(2)) and 113,510 had a late start (eGFR ≤5 ml/min per 1.73 m(2)). The following variables were significantly (P < 0.001) associated with an early start: white race, male gender, greater comorbidity index, presence of diabetes, and peritoneal dialysis. Compared with the reference group with an eGFR of >5 to 10 ml/min per 1.73 m(2) at dialysis start, a Cox model adjusted for potential confounding variables showed an incremental increase in mortality associated with earlier dialysis start. The group with the earliest start had increased risk of mortality, wheras late start was associated with reduced risk of mortality. Subgroup analyses showed similar results. The limitations of the study are retrospective study design, potential unaccounted confounding, and potential selection and lead-time biases.

CONCLUSIONS

Late initiation of dialysis is associated with a reduced risk of mortality, arguing against aggressive early dialysis initiation based primarily on eGFR alone.

International trends in erythropoietin use and hemoglobin levels in hemodialysis patients

Hemoglobin levels and the dose of erythropoiesis-stimulating agents (ESAs) have risen over time in hemodialysis patients within the United States. There are concerns that these trends may be driven by reimbursement policies that provide potential incentives to increase this use. To determine this we studied trends in the use of ESA and hemoglobin levels in hemodialysis patients and the relationship of these trends to the mode of reimbursement. Using the Dialysis Outcomes and Practice Patterns Study (DOPPS) database of hemodialysis we analyzed facility practices in over 300 randomly selected dialysis units in 12 countries. At each of three phases (years 1996-2001, 2002-2004, and 2005-present), we randomly selected over 7500 prevalent hemodialysis, hemofiltration, or hemodiafiltration patients. ESA usage rose significantly in every country studied except Belgium. All but Sweden demonstrated a substantial increase in hemoglobin levels. In 2005 more than 40% of patients had hemoglobin levels above the KDOQI upper target limit of 120 g/l in all but Japan. These trends appeared to be independent of the manner of reimbursement even though the United States is the only country with significant financial incentives promoting increased use of these agents. Thus, our study found that prescribing higher doses of ESAs and achieving higher hemoglobin levels by physicians reflects a broad trend across DOPPS countries regardless of the reimbursement policies.

A Change from Subcutaneous to Intravenous Erythropoietin Increases the Cost of Anemia Therapy

BACKGROUND

It seems that more erythropoietin (EPO) is required when given intravenously (IV) than when given subcutaneously (SC). Estimates of the magnitude of this difference vary widely, impeding development of economic models in this area. Concerns about pure red cell aplasia led our program to switch from SC to IV EPO, so we studied the impact of this change on the cost of anemia therapy.

METHODS

All in-center hemodialysis patients who had received EPO for at least 3 months prior to and following conversion to IV EPO were studied. Data was obtained retrospectively for 1 year prior to and prospectively for 1 year following conversion. The costs of anemia therapy (EPO, transfusions and iron) were calculated from the hospital's perspective.

RESULTS

158 patients were studied. One month after switching, the hemoglobin fell significantly, reaching a nadir at 3 months. This triggered more use of EPO, iron and transfusions. By month 7 hemoglobin levels had returned to initial levels, with a median rise in EPO dose of 1,250 units/week (p < 0.001). After the switch, the median rise in total anemia therapy costs was 13.1% (CAD 665/patient-year, p < 0.01).

CONCLUSIONS

Conversion of EPO from SC to IV dosing increased the costs of anemia therapy at our center.