How does darbepoetin compare to epoetin in cancer patients?

How does darbepoetin compare to epoetin in cancer patients?

Comment by InpharmD Researcher

Studies providing a direct clinical comparison between epoetin and darbepoetin in cancer patients are relatively dated, all having been conducted prior to 2010. Results of these studies generally reflect comparable efficacy and safety outcomes between the two erythropoiesis-stimulating agents. Subsequently, relevant guidelines do not specify a preference for either agent. Selection of agent may be based on clinician preference, cost/availability, and preferred dosing regimen.

darbepoetin vs epoetin oncology cancer malignancy

Background

Across the 2007, 2010, and 2019 American Society of Clinical Oncology (ASCO)/American Society of Hematology (ASH) guidelines, epoetin and darbepoetin are considered equivalent in effectiveness and safety, with no clinical preference for either agent. The 2007 guideline found no clinically significant differences in hematologic response, transfusion rates, or thromboembolic events; evidence was insufficient to establish differences in quality of life, tumor outcomes, survival, or other adverse effects. The 2010 update retained this conclusion because no new comparative studies had emerged, and the 2019 update again found similar efficacy and safety in subgroup analyses; although one analysis suggested greater fatigue improvement with epoetin, the panel considered the finding potentially confounded and did not change its equivalence determination. [1], [2], [3]

Both agents are subject to the same clinical restrictions and class risks, including increased thromboembolism. Discussion in the 2007 guideline permitted use of either agent when hemoglobin was approaching or below 10 g/dL, whereas the 2010 guideline narrowed initiation to hemoglobin below 10 g/dL and emphasized using the lowest hemoglobin level sufficient to avoid transfusion because of evidence of shorter survival and thromboembolic risk. The 2019 guideline more explicitly limited either agent to selected patients with chemotherapy-associated anemia, hemoglobin below 10 g/dL, and noncurative treatment intent, while recommending against their use with curative-intent chemotherapy and in most patients not receiving chemotherapy, except qualifying patients with lower-risk myelodysplastic syndromes. The primary difference between the two medications is dosing regimens, as epoetin may be administered at 150 U/kg three times weekly or 40,000 U weekly, whereas darbepoetin may be administered at 2.25 μg/kg weekly or 500 μg every three weeks. [1], [2], [3]

Literature Review

A search of the published medical literature revealed 5 studies investigating the researchable question:

How does darbepoetin compare to epoetin in cancer patients?

Level of evidence

B - One high-quality study or multiple studies with limitations Read more→

Please see Tables 1-5 for your response.

Randomized Comparison of Every-2-Week Darbepoetin Alfa and Weekly Epoetin Alfa for the Treatment of Chemotherapy-Induced Anemia: The 20030125 Study Group Trial
Design	Randomized, open-label, active-controlled, multicenter study N= 1,220
Objective	To systematically compare the efficacy and safety of darbepoetin alfa (DA) and epoetin alfa (EA) using common doses and schedules used in clinical practice
Study Groups	DA 200 µg every two weeks (n= 606) EA 40,000 units every week (n= 603)
Inclusion Criteria	Patients with nonmyeloid malignancy, ≥ 8 weeks of planned chemotherapy, age ≥ 18 years, and anemia (hemoglobin ≤ 11 g/dL)
Exclusion Criteria	History of primary hematologic disorders causing anemia other than nonmyeloid malignancy; unstable/uncontrolled cardiac conditions; clinically significant inflammatory disease; neutralizing antibodies to recombinant human erythropoietin; EA or DA therapy within 4 weeks before randomization
Methods	Patients were randomly assigned to DA 200 µg every two weeks or EA 40,000 units every week for up to 16 weeks with identical dose adjustment rules. Efficacy was assessed by the incidence of RBC transfusion. Dose escalation was permitted at week 5 if hemoglobin increase was ≤ 1 g/dL. Study drug was withheld if hemoglobin exceeded 13 g/dL and reinstated at 75% of the previous dose after hemoglobin decreased to ≤ 12 g/dL
Duration	16-week treatment period with 2 weeks of follow-up for adverse events
Outcome Measures	Primary: Incidence of RBC transfusion from week 5 to the end of the treatment phase Secondary: Transfusion requirements over the entire treatment period, hemoglobin levels
Baseline Characteristics		Darbepoetin Alfa (n= 606)	Epoetin Alfa (n= 603)
	Female	415 (68%)	381 (63%)
	White	506 (83%)	502 (83%)
	Age, years	63.2 ± 12.4	63.7 ± 11.6
	Primary tumor type Breast Gastrointestinal Gynecologic Lung	131 (22%) 104 (17%) 60 (10%) 156 (26%)	126 (21%) 108 (18%) 41 (7%) 164 (27%)
	ECOG 0 to 1	518 (85%)	509 (84%)
	Baseline hemoglobin, g/dL	10.2 ± 0.9	10.2 ± 0.9
Results		Darbepoetin Alfa (n= 606)	Epoetin Alfa (n= 603)	p-value
	RBC transfusion incidence from week 5 to EOTP	21%	16%	<0.05
	Units transfused	2.3 (95% CI 2.1 to 2.5)	2.5 (95% CI 2.2 to 2.7)	-
	Mean hemoglobin change from baseline to EOTP	11.8 g/dL	11.8 g/dL	NS
	Patients achieving target hemoglobin (11-13 g/dL)	80%	86%	NS
Adverse Events	No significant differences in safety profiles between DA and EA. Cardiovascular/thromboembolic events reported in 6% of DA patients and 7% of EA patients. No antibodies to erythropoietic compounds detected.
Study Author Conclusions	This large, phase III study demonstrates comparable efficacy of DA Q2W and EA QW. Less frequent dosing offers potential benefits for patients, caregivers, and healthcare providers.
Critique	The study was well-designed with a large sample size and robust statistical analysis, providing strong evidence for the noninferiority of DA compared to EA. However, the open-label design may introduce bias, and the exclusion of the first month in the primary endpoint analysis could overlook early differences in treatment response. Additionally, the study did not collect long-term survival and tumor progression data, which could be relevant for comprehensive safety evaluation.

Table 1 References:
[4] Glaspy J, Vadhan-Raj S, et al. Randomized comparison of every-2-week darbepoetin alfa and weekly epoetin alfa for the treatment of chemotherapy-induced anemia: the 20030125 Study Group Trial. J Clin Oncol. 2006;24(15):2290-2297. doi:10.1200/JCO.2005.03.8570

Randomized Comparison of Epoetin Alfa (40,000 U Weekly) and Darbepoetin Alfa (200 μg Every 2 Weeks) in Anemic Patients with Cancer Receiving Chemotherapy
Design	Randomized, open-label, multicenter trial N= 358
Objective	To directly compare the hemoglobin (Hb) response to epoetin alfa (EPO), 40,000 U once weekly, with that to darbepoetin alfa (DARB), 200 μg every 2 weeks, in anemic patients with cancer receiving chemotherapy
Study Groups	EPO 40,000 U QW (n = 178) DARB 200 μg Q2W (n = 180)
Inclusion Criteria	Adults with solid tumors scheduled to receive chemotherapy for ≥12 weeks and with baseline Hb ≤11 g/dl
Exclusion Criteria	Received any erythropoietic agent within 3 months, anemia due to factors other than cancer or chemotherapy, more than two prior chemotherapy regimens, radiation therapy included in treatment plans, history of stem cell or bone marrow transplant, untreated brain metastases, uncontrolled hypertension, poorly controlled seizures, known hypersensitivity to mammalian cell–derived products or human albumin, transfusion of packed red blood cells within 28 days, any unstable medical condition, or a history of uncontrolled cardiac arrhythmias, pulmonary embolism, or thrombosis within the previous 6 months
Methods	Patients were randomized to receive either EPO 40,000 U QW or DARB 200 μg Q2W s.c. for up to 16 weeks. Doses were increased for nonresponders after 4 (EPO) or 6 (DARB) weeks, and reduced for rapid Hb rise or Hb level >13 g/dl. An oral supplement of ferrous sulfate, 325 mg, was taken daily if tolerated. Hb, Hct, and blood pressure were monitored weekly. QOL was assessed using specific subscales. Safety was assessed by laboratory tests, vital sign measurements, physical examinations, and the incidence and severity of AEs
Duration	Up to 16 weeks
Outcome Measures	Primary: Proportion of patients achieving a ≥1-g/dl Hb rise by week 5 Secondary: Proportion of patients achieving at least a 1- or 2-g/dl increase in Hb at week 9 or at the study end, time to response, transfusion requirements
Baseline Characteristics		Epoetin alfa (n = 178)	Darbepoetin alfa (n = 180)
	Age, years	62.1 ± 11.8	63.4 ± 11.8
	Female	109 (61.2%)	119 (66.1%)
	Weight, kg	72.8 ± 18.2	74.8 ± 19.6
	Hemoglobin, g/dL	10.16 ± 0.749	10.07 ± 0.787
	Transferrin saturation, %	20.23 ± 12.81	23.77 ± 19.76
	ECOG performance status score 0 1 2	57 (32.0%) 95 (53.4%) 26 (14.6%)	61 (33.9%) 89 (49.4%) 30 (16.7%)
	Chemotherapy type Platinum based Nonplatinum based	69 (38.8%) 109 (61.2%)	76 (42.2%) 104 (57.8%)
	Tumor type Lung Breast	47 (26.4%) 51 (28.7%)	47 (26.1%) 38 (21.1%)
Results		Epoetin Alfa (n= 178)	Darbepoetin Alfa (n= 180)	p-value
	Hb increase ≥1 g/dl by week 5	47.0%	32.5%	0.0078
	Hb increase ≥2 g/dl by study end	57.7%	41.8%	0.004
	Median time to Hb rise ≥1 g/dl, days	35.0	46.0	0.0057
	Mean PRBC units transfused per patient	2.5	3.9	0.0334
Adverse Events	The incidences and patterns of adverse events were similar between groups, with most being unrelated to the study treatment. Common adverse events included neutropenia (17% vs. 26%), nausea (33% vs. 27%), and diarrhea (26% vs. 20%). Clinically significant thrombotic vascular events were reported in 11% of epoetin alfa patients and 9% of darbepoetin alfa patients.
Study Author Conclusions	Epoetin alfa demonstrated an earlier hematologic response compared to darbepoetin alfa in anemic patients with cancer receiving chemotherapy. Transfusion intensity was significantly lower for epoetin alfa, although transfusion frequency was not. Both treatments provided similar improvements in quality of life and had similar safety profiles.
Critique	The study was well-designed as a prospective, randomized trial, providing a direct comparison of epoetin alfa and darbepoetin alfa. However, the open-label design may introduce bias, and the study did not explore long-term outcomes beyond the 16-week treatment period. Additionally, the study focused on patients with solid tumors, which may limit the applicability of the findings to other cancer types.

Table 2 References:
[5] Waltzman R, Croot C, Justice GR, Fesen MR, Charu V, Williams D. Randomized comparison of epoetin alfa (40,000 U weekly) and darbepoetin alfa (200 microg every 2 weeks) in anemic patients with cancer receiving chemotherapy. Oncologist. 2005;10(8):642-650. doi:10.1634/theoncologist.10-8-642

Treatment of Chemotherapy-Induced Anemia in Breast Cancer: Results of a Randomized Controlled Trial of Darbepoetin Alfa 200 μg Every 2 Weeks Versus Epoetin Alfa 40,000 U Weekly
Design	Phase II, open-label, randomized, multicenter trial N= 141
Objective	To quantify the efficacy of darbepoetin alfa compared with epoetin alfa in patients with breast cancer and to describe the safety profile of darbepoetin alfa compared with epoetin alfa
Study Groups	Darbepoetin alfa (n= 72) Epoetin alfa (n= 69)
Inclusion Criteria	Female patients with anemia (Hb level < 11 g/dL) and histologically confirmed breast cancer, age ≥18 years, anemia induced by chemotherapy, ≥8 planned additional cycles of chemotherapy, Karnofsky performance status ≥50%, and adequate liver and renal function
Exclusion Criteria	History of anemia caused by factors unrelated to chemotherapy, uncontrolled hypertension, active bleeding, red blood cell transfusion within 4 weeks of screening, erythropoietic therapy within 2 weeks of randomization, history of red cell aplasia, or known hypersensitivity to recombinant mammalian red cell growth factor product
Methods	Patients were randomized to receive darbepoetin alfa 200 μg every 2 weeks or epoetin alfa 40,000 U weekly for ≤16 weeks. Hemoglobin levels, transfusions, and adverse events were assessed every 2 weeks. Dose modifications were made to maintain appropriate Hb levels. Supplemental iron therapy was permitted according to institutional standards
Duration	October 2002 to December 2003
Outcome Measures	Primary: Mean change in hemoglobin (Hb) during treatment, mean Hb level at the end of treatment, proportion of patients exhibiting a hematopoietic response Secondary: Ability to achieve and maintain a target Hb range of 11-13 g/dL, safety profile, patient satisfaction with anemia treatment
Baseline Characteristics		Darbepoetin Alfa (n = 72)	Epoetin Alfa (n = 69)
	Female	72 (100%)	69 (100%)
	Age, years	53.6 ± 11.4	58.4 ± 12.5
	White	58 (81%)	57 (83%)
	Disease Stage I/II III IV	37 (51%) 11 (15%) 22 (31%)	26 (38%) 13 (19%) 26 (38%)
	Previous Radiation Therapy	9 (13%)	10 (14%)
	Previous Chemotherapy ≥ 1 Previous regimen > 2 Previous regimens	23 (32%) 8 (11%)	32 (46%) 15 (22%)
	Mean Hemoglobin Level, g/dL	10.5 ± 0.8	10.6 ± 0.7
	Mean Serum Ferritin, ng/mL	336.3 ± 319.8	290 ± 260.3
	Mean Transferrin Saturation, %	27.32 ± 17.11	29.28 ± 21.82
	Iron Supplementation	72 (100%)	69 (100%)
Results		Darbepoetin Alfa (n = 72)	Epoetin Alfa (n = 69)
	Mean change in Hb level from baseline, g/dL	1.9 ± 1.5	1.7 ± 1.4
	Hematopoietic response (≥2 g/dL increase or Hb ≥12 g/dL)	88% (95% CI, 80%-95%)	81% (95% CI, 72%-90%)
	Proportion of patients receiving transfusion	6% (95% CI, 0-11%)	16% (95% CI, 7%-25%)
	Patients achieving target Hb level ≥11 g/dL	93%	90%
	Median time to target Hb level, weeks	3 (95% CI, 3-5)	4 (95% CI, 3-5)
	No significant differences observed between groups.
Adverse Events	11 patients in the darbepoetin alfa group (15%) and 16 in the epoetin alfa group (24%) had ≥1 serious adverse event. No thrombotic events were reported for either group during treatment.
Study Author Conclusions	Darbepoetin alfa 200 μg every 2 weeks and epoetin alfa 40,000 U weekly achieve similar hematologic and transfusion-based outcomes as well as patient satisfaction with erythropoietic treatment in patients with breast cancer.
Critique	The study provides valuable comparative data on the efficacy and safety of darbepoetin alfa and epoetin alfa in breast cancer patients with chemotherapy-induced anemia. However, the lack of formal hypothesis testing limits the ability to draw definitive conclusions about noninferiority. The study's generalizability to other tumor types needs confirmation in larger trials. Despite these limitations, the study's findings are consistent with previous research on erythropoietic agents.

Table 3 References:
[6] Senecal FM, Yee L, Gabrail N, et al. Treatment of chemotherapy-induced anemia in breast cancer: results of a randomized controlled trial of darbepoetin alfa 200 microg every 2 weeks versus epoetin alfa 40,000 U weekly. Clin Breast Cancer. 2005;6(5):446-454. doi:10.3816/cbc.2005.n.050

A Randomized Comparison of Every-2-Week Darbepoetin Alfa and Weekly Epoetin Alfa for the Treatment of Chemotherapy-Induced Anemia in Patients With Breast, Lung, or Gynecologic Cancer
Design	Three concurrent randomized, open-label, multicenter, identical trials N= 312
Objective	To validate the Patient Satisfaction Questionnaire for Anemia (PSQ-An) treatment tool and to compare the efficacies and safety profiles of darbepoetin alfa and epoetin alfa in patients with chemotherapy-induced anemia
Study Groups	Darbepoetin alfa (n= 157) Epoetin alfa (n= 155)
Inclusion Criteria	Patients with a diagnosis of breast cancer, NSCLC (stage IIIb or IV), or gynecologic carcinoma; ≥18 years old; anemic (hemoglobin ≤11 g/dl at screening); planned concurrent chemotherapy for at least 8 additional weeks; KPS score ≥50%; adequate renal and liver function; ability to complete questionnaires
Exclusion Criteria	Received an RBC transfusion within 4 weeks of screening or erythropoietic therapy within 2 weeks of randomization; inadequate iron stores; known positive antibody response to any erythropoietic agent; history of pure red cell aplasia, uncontrolled hypertension, or anemia due to a hematologic disorder other than chemotherapy-induced anemia
Methods	Patients were randomized 1:1 to receive either darbepoetin alfa at 200 µg Q2W or epoetin alfa at 40,000 U QW for up to 16 weeks. Hemoglobin concentrations were measured at baseline and Q2W. The PSQ-An was administered during treatment and at the end of the study. Doses were adjusted based on hemoglobin levels.
Duration	October 2002 to December 2003
Outcome Measures	Hemoglobin- and transfusion-based efficacy endpoints, safety profiles
Baseline Characteristics		Darbepoetin alfa (n= 157)	Epoetin alfa (n= 155)
	Female	134 (85%)	129 (83%)
	Caucasian	132 (84%)	131 (85%)
	Age, years	58.7 ± 11.5	61.7 ± 12.1
	Tumor type Breast NSCLC (IIIb/IV) Gynecologic	72 (46%) 51 (32%) 34 (22%)	69 (45%) 51 (33%) 35 (23%)
Results		Darbepoetin alfa (n= 157)	Epoetin alfa (n= 155)
	Patients achieving target hemoglobin ≥11 g/dl	124 (82%)	128 (86%)
	Median time to target hemoglobin (weeks)	5	4
	Mean hemoglobin level after achieving target (g/dl)	12.1	12.2
	No significant differences observed between groups.
Adverse Events	One episode of deep venous thrombosis in each treatment group; one episode of pulmonary embolism in the epoetin alfa group.
Study Author Conclusions	Darbepoetin alfa (200 µg Q2W) and epoetin alfa (40,000 U QW) appear to achieve comparable clinical and hematologic outcomes. The PSQ-An enables formal comparisons of the impact of anemia therapies on patients and caregivers in future studies.
Critique	The study provided valuable data on the comparability of darbepoetin alfa and epoetin alfa, but was not powered to test noninferiority. The primary focus was on validating the PSQ-An, not on comparing patient satisfaction between treatment groups. Future studies should address these limitations and explore patient satisfaction more comprehensively.

Table 4 References:
[7] Schwartzberg LS, Yee LK, Senecal FM, et al. A randomized comparison of every-2-week darbepoetin alfa and weekly epoetin alfa for the treatment of chemotherapy-induced anemia in patients with breast, lung, or gynecologic cancer. The Oncologist. 2004;9(6):696-707. doi:10.1634/theoncologist.9-6-696

Economic Evaluation of Weekly Epoetin Alfa versus Biweekly Darbepoetin Alfa for Chemotherapy-Induced Anaemia
Design	16-week, open-label, multicentre, randomised trial N= 358
Objective	To compare resource use, costs and clinical outcomes between weekly epoetin alfa and biweekly darbepoetin alfa in patients with chemotherapy-induced anaemia using a cost-consequences framework
Study Groups	Epoetin alfa (n= 178) Darbepoetin alfa (n= 180)
Inclusion Criteria	Patients with solid-tumour malignancy, aged ≥18 years, with haemoglobin level ≤11 g/dL, scheduled to receive cyclic chemotherapy for at least 12 weeks
Exclusion Criteria	Not specified
Methods	Patients were randomised to receive either weekly epoetin alfa 40,000 units or biweekly darbepoetin alfa 200μg. Costs were assigned using US Medicare reimbursement rates and indirect costs based on mean hourly wage. Clinical outcomes included haemoglobin levels and transfusions. Sensitivity analyses evaluated different costing methods and perspectives.
Duration	16 weeks
Outcome Measures	Primary: Proportion of patients experiencing a ≥1 g/dL rise in hemoglobin by week 5 (i.e., hemoglobin response) Secondary: Hematological response (≥2 g/dL rise by week 9), AUC for change in hemoglobin, mean hemoglobin levels at weeks 5, 9, 13, and 17, proportion of patients with hemoglobin ≥11 g/dL by weeks 5 and 9
Baseline Characteristics		Epoetin alfa (n = 175)	Darbepoetin alfa (n = 177)
	Female	107 (61.1%)	118 (66.7%)
	Age, years (mean, SD)	62.0 (11.7)	63.3 (11.8)
	Type of cancer Breast Lung Other	38 (21.7%) 45 (25.7%) 92 (52.6%)	50 (28.2%) 46 (26.0%) 81 (45.8%)
	Baseline haemoglobin level, g/dL (mean, SD)	10.1 (0.76)	10.0 (0.82)
	Baseline ECOG status Fully active Strenuous activity limited Self-care but no work	57 (32.6%) 92 (52.6%) 26 (14.9%)	61 (34.5%) 87 (49.2%) 29 (16.4%)
	Platinum chemotherapy	68 (38.9%)	75 (42.4%)
Results		Epoetin alfa (n = 175)	Darbepoetin alfa (n = 177)	p-value or difference (95% CI)
	Within-trial resource used
	Patients hospitalized	43 (24.6%)	39 (22.0%)	0.57
	Hospitalizations	0.34 (0.72%)	0.27 (0.55%)	0.72
	Inpatient days	2.61 ± 6.00	1.58 ± 4.10	1.03 (0.074 to 2.27)
	Blood transfusions	0.26 ± 0.65	0.45 ± 1.08	-0.19 (-0.37 to -0.009)
	Units of blood transfused	0.46 ± 1.19	0.88 ± 2.11	-0.42 (-0.77 to -0.08)
	Days of unplanned radiation therapy	0.31 ± 2.97	0.71 ± 4.38	-0.40 (-1.24 to 0.29)
	Response metrics
	Hemoglobin response	78 (44.6%)	60 (33.9%)	10.7 (1.7 to 20.6)
	Hematological response	78 (44.6%)	48 (27.1%)	17.5 (8.0 to 26.7)
	AUC for change in hemoglobin, g/dL	11.1 ± 13.5	6.0 ± 13.8	5.1 (2.4 to 7.7)
	Hemoglobin level, g/dL Week 5 Week 9 Week 13 Week 17	10.9 ± 1.5 11.2 ± 1.5 11.4 ± 1.4 11.4 ± 1.5	10.4 ± 1.4 10.6 ± 1.7 10.8 ± 1.7 10.9 ± 1.8	0.5 (0.3 to 0.9) 0.6 (0.3 to 1.0) 0.6 (0.3 to 1.0) 0.5 (0.2 to 0.9)
	Patients with hemoglobin ≥ 11 g/dL By week 5 By week 9	98 (56%) 125 (71.4%)	79 (44.6%) 105 (59.3%)	11.4 (0.4 to 21.0) 12.1 (1.3 to 21.3)
Adverse Events	N/A
Study Author Conclusions	Most clinical outcome measures suggested greater improvement with epoetin alfa relative to darbepoetin alfa, but most costs for both agents appeared similar. Decision makers must evaluate the differences in costs and efficacy measures that are most relevant from their perspectives.
Critique	The study's strengths include its randomised design and detailed cost analysis. However, the open-label design may introduce bias, and the short follow-up period limits the assessment of long-term outcomes. Additionally, the study did not account for potential differences in patient management practices across sites, which could affect resource use and costs.

Table 5 References:
[8] Reed SD, Radeva JI, Daniel DB, et al. Economic evaluation of weekly epoetin alfa versus biweekly darbepoetin alfa for chemotherapy-induced anaemia: evidence from a 16-week randomised trial. Pharmacoeconomics. 2006;24(5):479-494. doi:10.2165/00019053-200624050-00006