Comparison of Aranesp with Procrit in terms of efficacy and cost.
Researchers reported new data showing that Amgen's new anemia-fighting compound darbepoetin alfa (Aranesp), dosed half as often as standard epoetin alfa (Procrit, OrthoBiotech) with the same therapeutic effect, costs 13% less than the conventional agent.
Plunging into the touchy question of costs shortly after Aranesp was approved in July, the researchers used clinical data from a recently published 12-week phase II randomized clinical trial. They based their cost estimates on the average wholesale prices posted in the 2002 Red Book. Additionally, they designed their 20-week model from a third-party payer perspective. (Duration of clinical trials in the recent literature ranged from 15-28 weeks.)
"We looked at the hemoglobin response to four different dosing schedules of Aranesp administered every two weeks to anemic cancer patients on chemotherapy," explained lead investigator John A. Glaspy, M.D., director of the Bowyer Oncology Outpatient Clinic and co-chief of the division of hematology and oncology, UCLA School of Medicine.
"The active control was a randomized group of Procrit patients receiving 40,000 Units weekly with dose escalated to 60,000 Units at six weeks for inadequate response."
Glaspy particularly noted three findings in the poster study presented recently at the American Society of Hematology meeting held in Philadelphia:
*The response of patients to the dose of 200 mcg of darbepoetin alfa every second week was identical to the response to epoetin alfa dosing of 40,000 Units once weekly escalated to 60,000 Units when needed.
*Compared with the estimated 20-week cost of darbepoetin alfa, epoetin alfa was estimated to be more than 13% more expensive per patient.
*Hemoglobin response rates (percentage of patients with a hemoglobin increase of 2 gm/dl from baseline, in the absence of RBC transfusion) were 60% at week 12 for both regimens.
The California scientists worked only with the dollar costs of the two agents. They did not include quality-of-life costs associated with anemiafor example, time lost from work by patients and caregivers or hours spent traveling to the clinic and back. But Glaspy called anemia itself an expensive disorder, with serious social implications. "The purpose of the study was to answer the question clinicians frequently ask: Is it more expensive or less expensive to use epoetin at 40,000 Units a week or darbepoetin at 200 mcg every other week?" he said in an interview.
The researchers found the cost-effectiveness ratio (cost per percentage of patients with hemoglobin response) was superior for darbepoetin alfa ($16,633 versus $18,812). "Not only is it used less often, it has a lower average wholesale price," Glaspy pointed out. "These benefits, plus fewer office visits, make [the new compound] a viable treatment option." The average 20-week cost for darbepoetin alfa at the usual dose of 200 mcg every other week was $9,980 per patient, he said, "more than 11.5% lower than the average cost of $11,287 per patient for epoetin alfa 40,000 Units [raised to 60,000 when needed]."
For the 12-week duration of the trial, darbepoetin alfa provided more than a 10% cost savings; average cost for each drug was $5,988 for darbepoetin, and $6,669 for epoetin.
His team's findings in clinical trials are still controversial, at least in the opinion of conservative clinicians, Glaspy acknowledged. "But doctors who have confidence in our findings can feel comfortable, knowing that costs of treating anemia will drop further with Aranesp," he predicted. Also, new study data presented by other researchers "confirm the accuracy of our results." As for hospital pharmacists, he commented: "The fact that equal results can be produced with a dose of this drug that is cost-competitive should also make the pharmacist feel more comfortable [about using it in the hospital] ... I think we do have a competitive marketplace, which is always best for patients."
Robert E. Smith Jr., M.D., president, South Carolina Oncology Associates, in Columbiaan anemia specialist not connected with the studytold Drug Topics that based on this study and data from other recent studies, "what will likely happen in the community is that some patients on 200 mcg of Aranesp every other week who are not responding well will have their dose increased to 300 mcg.... In these patients, we'll probably end up with costs equivalent to that of a Procrit regimenbut with better response rates and more responders."
Naomi PFEIFFER. Study shows new anemia drug costs less than standard of care.