Amgen Inc. said head-to-head studies of Aranesp dosed every two weeks vs. epoetin alfa (or Procrit) dosed once a week showed similar results in boosting hemoglobin and reducing the need for blood transfusions in cancer patients with chemotherapy-induced anemia.
Amgen, of Thousand Oaks, Calif., presented the data at the 40th annual American Society of Clinical Oncology meeting in New Orleans. Amgen released analyses of the three head-to-head trials, plus a separate single trial in which Aranesp (darbepoetin alfa) was dosed every three weeks.
"The head-to-head trials show that both products are comparable in efficacy, but that Aranesp offers benefits of less frequent dosing, which means that patients don't have to come into the office as often," Amgen spokeswoman Kelly Stoddard told BioWorld Today. "Being able to extend dosing out makes a difference financially to the physician's office, patients and caregivers."
Aranesp and Procrit, both anemia drugs, got caught up in a controversy in November 2002 when the Centers for Medicare and Medicaid Services said it would reimburse the drugs in the hospital outpatient setting at the same rate because they are "functionally equivalent." Procrit is made by Ortho Biotech Products LP, a division of New Brunswick, N.J.-based Johnson & Johnson, and was licensed from Amgen, which sells the drug in other indications under the name Epogen. Aranesp is the second generation of Epogen. (See BioWorld Today, Nov. 4, 2002, and Dec. 27, 2002.)
Amgen had argued that when dosed properly, Aranesp and Procrit were not equal.
Stoddard said Amgen commissioned the head-to-head studies because of questions from physicians. "They were not necessarily asking which one is better, but what are the differences between them," she said.
Mark Wolfe, a spokesman for Ortho Biotech, told BioWorld Today the company would not be commenting on Amgen's studies.
The analysis presented at ASCO included data on 312 patients across the three studies with breast, non-small-cell lung and gynecological cancers who were randomized to receive either Aranesp 200 mcg every two weeks or epoetin alfa 40,000 U every week. Whether treated with Aranesp or epoetin alfa, patients in the study achieved target hemoglobin of greater than or equal to 11 g/dL and had similar transfusion rates.
The results were analyzed based on the achievement and maintenance of that target hemoglobin threshold and range (11-13 g/dL, which is based on the ASH/ASCO and National Comprehensive Cancer Network guidelines for cancer and treatment-related anemia). Patients in both arms of the studies achieved and maintained hemoglobin levels of 11-13 g/dL. The median time to reach the target hemoglobin level was five weeks in the Aranesp group and four weeks in the epoetin alfa group. After achieving the target hemoglobin level, 81 percent of patients in the Aranesp group remained in the target range compared to 75 percent in the epoetin alfa group.
Meanwhile, Amgen said patients dosed with Aranesp every three weeks achieved and maintained target hemoglobin levels as recommended by clinical guidelines.
The analysis includes data from a randomized, open-label, multicenter study of 204 patients with chemotherapy-induced anemia. Patients were randomized into two groups: baseline hemoglobin of greater than or equal to 10.5 g/dL (early intervention) and less than or equal to 12 g/dL (observation/late intervention).
Results of that study indicate that patients with chemotherapy-induced anemia who received Aranesp 300 mcg every three weeks were able to maintain optimal hemoglobin levels between 11 and 13 g/dL after early intervention as well as correct anemia in patients with hemoglobin levels below 10 g/dL. About 97 percent of patients in the early intervention group attained the target hemoglobin range. After late treatment with Aranesp, mean hemoglobin improved in most patients, with 90 percent of patients achieving hemoglobin values within the target range. More than 90 percent of both early and late-intervention patients achieved the target hemoglobin of greater than or equal to 11 g/dL with mean hemoglobin near 12 g/dL for the remainder of the study.