Patients with chronic kidney disease on dialysis: ESA effects on rates of transfusion
In early clinical studies conducted in patients with CKD on dialysis, ESAs have been shown to reduce the use of RBC transfusions. These studies enrolled patients with mean baseline hemoglobin levels of approximately 7.5 g/dL and ESAs were generally titrated to achieve a hemoglobin level of approximately 12 g/dL. Fewer transfusions were given during the ESA treatment period when compared to a pre-treatment interval.
In the Normal Hematocrit Study, the yearly transfusion rate was 51.5% in the lower hemoglobin group (10 g/dL) and 32.4% in the higher hemoglobin group (14 g/dL).
Patients with chronic kidney disease not on dialysis: ESA effects on rates of transfusion
In TREAT, a randomized, double-blind trial of 4038 patients with CKD and type 2 diabetes not on dialysis, a post-hoc analysis showed that the proportion of patients receiving RBC transfusions was lower in patients administered Aranesp to target a hemoglobin of 13 g/dL compared to the control arm in which Aranesp was administered intermittently if hemoglobin concentration decreased to less than 9 g/dL (15% versus 25%, respectively). In CHOIR, a randomized open-label study of 1432 patients with CKD not on dialysis, use of an ESA to target a higher (13.5 g/dL) versus lower (11.3 g/dL) hemoglobin goal did not reduce the use of RBC transfusions. In each trial, no benefits occurred for the cardiovascular or end-stage renal disease outcomes. In each trial, the potential benefit of ESA therapy was offset by worse cardiovascular safety outcomes resulting in an unfavorable benefit-risk profile [see Warnings and Precautions (5.1)].
ESA Effects on quality of life
Aranesp use has not been demonstrated in controlled clinical trials to improve quality of life, fatigue, or patient well-being.
ESA Effects on rates of death and other serious cardiac adverse events
Three randomized outcome trials (Normal Hematocrit Study [NHS], Correction of Anemia with Epoetin Alfa in Chronic Kidney Disease [CHOIR], and Trial of Darbepoetin Alfa in Type 2 Diabetes and CKD [TREAT]) have been conducted in patients with CKD using Epogen/PROCRIT/Aranesp to target higher vs. lower hemoglobin levels. Though these trials were designed to establish a cardiovascular or renal benefit of targeting higher hemoglobin levels, in all 3 studies, patients randomized to the higher hemoglobin target experienced worse cardiovascular outcomes and showed no reduction in progression to ESRD. In each trial, the potential benefit of ESA therapy was offset by worse cardiovascular safety outcomes resulting in an unfavorable benefit-risk profile [see Warnings and Precautions (5.1)].
Other ESA trials
Three studies (2 in adults and 1 in pediatric patients) evaluated the safety and efficacy of the de novo use of Aranesp for the correction of anemia in patients with CKD, and 3 studies (2 in adults and 1 in pediatric patients) assessed the ability of Aranesp to maintain hemoglobin concentrations in patients with CKD who had been receiving other recombinant erythropoietins.
De Novo Use of Aranesp
Adult Patients
Once Weekly Aranesp Starting Dose
In 2 randomized, open-label studies, Aranesp or epoetin alfa was administered for the correction of anemia in patients with CKD who had not been receiving prior treatment with exogenous erythropoietin. Study N1 evaluated patients with CKD receiving dialysis; Study N2 evaluated patients not requiring dialysis. In both studies, the starting dose of Aranesp was 0.45 mcg/kg administered once weekly. The starting dose of epoetin alfa was 50 Units/kg 3 times weekly in Study N1 and 50 Units/kg twice weekly in Study N2. When necessary, dosage adjustments were instituted to maintain hemoglobin in the study target range of 11 to 13 g/dL. (Note: The recommended hemoglobin target range is lower than the target range of these studies [see Dosage and Administration (2.2)].) The primary efficacy endpoint was the proportion of patients who experienced at least a 1 g/dL increase in hemoglobin concentration to a level of at least 11 g/dL by 20 weeks (Study N1) or 24 weeks (Study N2). The studies were designed to assess the safety and effectiveness of Aranesp but not to support conclusions regarding comparisons between the 2 products.
In Study N1, the primary efficacy endpoint was achieved by 72% (95% CI: 62%, 81%) of the 90 patients treated with Aranesp and 84% (95% CI: 66%, 95%) of the 31 patients treated with epoetin alfa. The mean increase in hemoglobin over the initial 4 weeks of Aranesp treatment was 1.1 g/dL (95% CI: 0.82 g/dL, 1.37 g/dL).
In Study N2, the primary efficacy endpoint was achieved by 93% (95% CI: 87%, 97%) of the 129 patients treated with Aranesp and 92% (95% CI: 78%, 98%) of the 37 patients treated with epoetin alfa. The mean increase in hemoglobin from baseline through the initial 4 weeks of Aranesp treatment was 1.38 g/dL (95% CI: 1.21 g/dL, 1.55 g/dL).
Once Every 2 Week Aranesp Starting Dose
In 2 single-arm studies (N3 and N4), Aranesp was administered for the correction of anemia in patients with CKD not receiving dialysis. In both studies, the starting dose of Aranesp was 0.75 mcg/kg administered once every 2 weeks.
In Study N3 (study duration of 18 weeks), the hemoglobin goal (hemoglobin concentration ≥ 11 g/dL) was achieved by 92% (95% CI: 86%, 96%) of the 128 patients treated with Aranesp.
In Study N4 (study duration of 24 weeks), the hemoglobin goal (hemoglobin concentration of 11 to 13 g/dL) was achieved by 85% (95% CI: 77%, 93%) of the 75 patients treated with Aranesp.
Pediatric Patients
Study N8 was a double-blind, randomized, controlled study in 114 pediatric patients from 1 to 18 years of age receiving darbepoetin alfa. In this study, pediatric patients with CKD receiving or not receiving dialysis who were anemic (hemoglobin [Hb] < 10.0 g/dL) and not being treated with an erythropoiesis stimulating agent (ESA) received darbepoetin alfa weekly or once every 2 weeks for the correction of anemia.
The primary efficacy endpoint was proportion of patients having hemoglobin corrected to ≥ 10.0 g/dL at any time point after the first dose without receiving any red blood cell transfusions after randomization and within 90 days prior to the Hb measurement. For pediatric patients receiving QW dosing, 98% (95% CI: 91%-100%), had hemoglobin concentrations corrected to ≥ 10 g/dL. For those receiving Q2W dosing, 84% (95% CI: 72%-92%), had hemoglobin concentrations corrected to ≥ 10 g/dL. The study was designed to assess the safety and effectiveness of Aranesp but not to support conclusions regarding comparisons between the 2 regimens.
Conversion from Other Recombinant Erythropoietins
Two studies of adults (N5 and N6) and 1 study in pediatric patients (N7) were conducted in patients who had been receiving other recombinant erythropoietins for treatment of the anemia due to CKD. The studies compared the abilities of Aranesp and other erythropoietins to maintain hemoglobin concentrations within a study target range of 9 to 13 g/dL in adults and 10 to 12.5 g/dL in pediatric patients. (Note: The recommended hemoglobin target is lower than the target range of these studies [see Dosage and Administration (2.2)].) Patients who had been receiving stable doses of other recombinant erythropoietins were randomized to Aranesp or continued with their prior erythropoietin at the previous dose and schedule. For patients randomized to Aranesp, the initial weekly dose was determined on the basis of the previous total weekly dose of recombinant erythropoietin.
Adult Patients
Study N5 was a double-blind study in which 169 hemodialysis patients were randomized to treatment with Aranesp and 338 patients continued on epoetin alfa. Study N6 was an open-label study in which 347 patients were randomized to treatment with Aranesp and 175 patients were randomized to continue on epoetin alfa or epoetin beta. Of the patients randomized to Aranesp, 92% were receiving hemodialysis and 8% were receiving peritoneal dialysis.
In Study N5, a median weekly dose of 0.53 mcg/kg Aranesp (25th, 75th percentiles: 0.30, 0.93 mcg/kg) was required to maintain hemoglobin in the study target range. In Study N6, a median weekly dose of 0.41 mcg/kg Aranesp (25th, 75th percentiles: 0.26, 0.65 mcg/kg) was required to maintain hemoglobin in the study target range.
Pediatric Patients
Study N7 was an open-label, randomized study conducted in the United States in pediatric patients from 1 to 18 years of age with CKD receiving or not receiving dialysis. Eighty-one patients with hemoglobin concentrations that were stable on epoetin alfa received Aranesp (subcutaneously or intravenously), and 42 patients continued to receive epoetin alfa at the current dose, schedule, and route of administration. Patients received Aranesp once weekly if previously receiving epoetin alfa 2 or 3 times weekly or once every other week if previously receiving epoetin alfa weekly. A median weekly dose of 0.41 mcg/kg Aranesp (25th, 75th percentiles: 0.25, 0.82 mcg/kg) was required to maintain hemoglobin in the study target range.