The cost-effectiveness of weekly epoetin alfa relative to weekly darbepoetin alfa in patients with chemotherapy-induced anemia.
OBJECTIVE
To compare the cost-effectiveness of epoetin alfa (EPO) and darbepoetin alfa (DARB) for the treatment of chemotherapy-induced anemia (CIA), using dosing regimens approved by the FDA (EPO 40,000 U once weekly and DARB 2.25 U once weekly and DARB 2.25 mcg/kg once weekly).


METHODS
The study compared published results of two double-blind, randomized, phase III trials one utilizing EPO (N = 166) and the other, DARB (N = 367). Patients in both trials similar baseline characteristics. Effectiveness was measured as the proportion of EPO or DARB patients who were successfully treated (i.e., did not require blood transfusion) during weeks 0-16 and 5-16, respectively. Estimated drug costs were presented in 2005 USD based on wholesale acquisition cost (WAC) and average drug utilization over 16 weeks. Cost-effectiveness was calculated as the estimated drug costs divided by transfusion effectiveness. Threshold analysis was used to determine the break-even point at which EPO and DARB had the same drug costs.


RESULTS
Estimated drug costs over 16 weeks were $9,039 for EPO and $13,555 for DARB. During weeks 5-16, 85% of EPO patients and 73% of DARB patients were successfully treated, resulting in average cost-effectiveness ratios of $106 for EPO and $186 for DARB per one per cent of successfully treated patients. A 33% reduction in DARB WAC was required to achieve the same drug costs as for EPO.


CONCLUSIONS
Utilizing FDA-approved doses, EPO was found to result in lower drug costs and better treatment success when compared to DARB. Hence, EPO is a dominant alternative compared to DARB for the treatment of CIA. The analyses presented here are not without limitations. Specifically, although the studies were comparable, patients were ultimately drawn from different populations.
Ben-Hamadi
R
R
Analysis Group, Inc. Boston, MA 02199, USA. mduh@analysisgroup.com
Duh
M S
MS
Aggarwal
J
J
Henckler
A
A
McKenzie
R S
RS
Tak Piech
C
C
D000740:Anemia / Q000139:chemically induced* / Q000188:drug therapy*; D000970:Antineoplastic Agents; D017326:Clinical Trials, Phase III as Topic; D000068256:Darbepoetin alfa; D004311:Double-Blind Method; D000068817:Epoetin Alfa; D004921:Erythropoietin / Q000008:administration & dosage* / Q000031:analogs & derivatives* / Q000191:economics*; D005260:Female; D006397:Hematinics / Q000008:administration & dosage* / Q000191:economics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy; D016032:Randomized Controlled Trials as Topic; D011994:Recombinant Proteins
D000970:Antineoplastic Agents; D006397:Hematinics; D011994:Recombinant Proteins; D004921:Erythropoietin; D000068256:Darbepoetin alfa; D000068817:Epoetin Alfa