Correspondence to: Marc VanAudenrode, Ph.D., Université Laval, Department DEconomique, Quebec City, Quebec, Canada G1K 7P4 (e-mail: mvand{at}ecn.ulaval.ca).
In a recent article in the Journal, Vansteenkiste et al. (1) presented the results of a randomized, double-blind, placebo-controlled trial of a weekly dosing regimen of darbepoetin alfa in anemic lung cancer patients receiving chemotherapy. Study endpoints included, among others, change in hemoglobin concentration and the number of days patients were hospitalized.
A review of the Vansteenkiste et al. (1) data and discussion reveals several unsupported inferences regarding the costs of using darbepoetin alfa. Vansteenkiste et al. (1) assert that patients receiving darbepoetin alfa "required shorter hospitalization stays than did patients receiving placebo," despite also stating that the study "was not designed to identify a causal relationship between hospitalization and the use of darbepoetin alfa, and the difference [between treatment and placebo] was not statistically significant." The authors (1) also claim that their results support a conclusion that darbepoetin alfa administered once-weekly requires ". . .less frequent administration [compared with epoetin alfa three-times-weekly] with concomitant increased patient compliance." However, this point is largely moot given that once-weekly use of epoetin alfa is currently the standard of care in oncologic anemia management today (2). Furthermore, the Vansteenkiste et al. (1) study did not measure patient compliance.
If the authors are comparing darbepoetin alfas cost of care with that of epoetin alfa, then it is relevant to note that they did not mention the percentage of patients requiring dose escalation, reported elsewhere as 67 (43%) of 156 patients (see 2002 package insert for Aranesp [darbepoetin alfa]; Amgen, Thousand Oaks, CA). Dose escalation for darbepoetin alfa results in a doubling of the dose and hence a doubling of drug costs from an average wholesale price (AWP) of $748.13 for 150 µg/week to an AWP of $1,496.25 for 300 µg/week (3). By contrast, in the event of a nonresponse to epoetin alfa, doses are escalated by only 50%, from 40 000 U at $534.24 (AWP) to 60 000 U at $801.36 (AWP) (3). The escalated dose of darbepoetin alfa is therefore 87% more expensive than that of epoetin alfa.
Vansteenkiste et al. (1) also state that "the ability to administer rHuEPO weekly seemingly requires a 33% increase in dose and cost compared with the thrice-weekly dose of 10 000 U." However, they do not report that the cost for the weekly starting dose of darbepoetin alfa is 40% [($748.13/$534.24) 1] more expensive than 40 000 U of epoetin alfa. Furthermore, the authors do not take into account the fact that, compared to thrice-weekly dosing, once-weekly epoetin alfas reduced dosing frequency permits a two-thirds reduction in visit and administration costs that partially offset the increased drug acquisition cost of $133.56/week. [The difference in starting weekly dose between epoetin alfa administered once-weekly and thrice-weekly is 10 000 U/week (40 000 U 30 000 U) (1,2). This difference in dose per week, 10 000 U, multiplied by the 2002 AWP ($.013356) (3) equals $133.56/week.]
Given their data, Vansteenkiste et al. (1) should have limited themselves to an analysis of the efficacy and safety of darbepoetin alfa versus placebo. The complex and important issues of health and/or economic benefits of anemia treatment and relative cost of darbepoetin alfa compared with those of other agents should be left to studies designed and powered to provide a full examination of these issues. Furthermore, on the sensitive issue of the relative costs of two competing drugs, authors should take care to present a balanced report based on complete, accurate, and appropriately powered statistical results.
NOTES
Editors note: Dr. VanAudenrode has provided consulting services for Ortho Biotech.
REFERENCES
1 Vansteenkiste J, Pirker R, Massuti B, Barata F, Font A, Fiegl M, et al. Double-blind, placebo-controlled, randomized phase III trial of darbepoetin alfa in lung cancer patients receiving chemotherapy. J Natl Cancer Inst 2002;94:121120.
2 Gabrilove JL, Cleeland CS, Livingston RB, Sarokhan B, Winer E, Einhorn LH. Clinical evaluation of once-weekly dosing of epoetin alfa in chemotherapy patients: improvements in hemoglobin and quality of life are similar to three-times-weekly dosing. J Clin Oncol 2001;19:287582.
3 Drug topics red book, 2002. Montvale (NJ): Medical Economics Co., Inc.; 2002. p. 215, 506.
![]() |
||||
|
Oxford University Press Privacy Policy and Legal Statement |