"High-Dose Epoetin Alfa (Procrit) Every 3 Weeks Effective for Chemotherapy-Induced Anemia: Presented at ASH"
By Bruce Sylvester
ATLANTA, GA -- December 14, 2005 -- Epoetin alfa (Procrit) 80,000 units administered every 3 weeks to patients on an every-3-week chemotherapy regimen is an effective treatment regimen for chemotherapy-induced anemia, researchers report.
The findings were presented here on December 12[th at the 47th Annual Meeting of the American Society of Hematology (ASH).
"The idea was to try to figure out how to treat these patients less often," said lead investigator Vernon Montoya, MD, hematologist in private practice in Alachua, Florida, who conducted his study with researchers at Ortho Biotech Clinical Affairs, Bridgewater, New Jersey.
"We hypothesized that if we could give a larger dose every 3 weeks, then patients might be able to maintain their hemoglobin and not have the side effects of chemotherapy, or have fewer problems with side effects related to chemotherapy," Dr. Montoya said.
"We developed a way to load patients up with a lower dose and then maintain them on a higher dose so they don't have to visit [hospital] as often," he said. "Maintaining their blood count will lessen the chance of their needing transfusions and also reduce feelings of fatigue and other symptoms associated with anemia."
The open-label, multicenter study had an initiation phase (IP) of 60,000 U/week to achieve target hemoglobin (Hb) of 12 g/dL with a maximum duration of 12 weeks, followed by a maintenance phase (MP) of 80,000 U every 3 weeks to maintain Hb between 11.0 and 12.5 g/dL.
Only subjects who achieved Hb of 12 g/dL in the initiation phase entered the maintenance phase. When subjects achieved target Hb, they proceeded to maintenance phase at the start of their next full chemotherapy cycle.
Patients were withdrawn from the maintenance phase if Hb decreased to less than 11 g/dL.
Doses were maintained for subjects reaching Hb levels above 13 g/dL and reduced in subjects showing a rate of rise greater than 1.3 g/dL every 2 weeks.
The maximum duration of the study, including both phases, was 24 weeks.
The investigators enrolled 155 subjects, 18 years and older, who were diagnosed with nonmyeloid malignancy, had a baseline Hb of 11 g/dL or lower, and chemotherapy planned for every 3 weeks for 15 weeks or more.
Study endpoints included proportion of patients achieving hematopoietic response (HR) in the IP (2-g/dL Hb increase from baseline or Hb of 12 g/dL) and proportion maintaining mean Hb between 11.0 and 12.5 g/dL in the maintenance phase.
Mean age of subjects was 62.2 years, 66.1% were female, mean baseline Hb was 10.2 0.8 g/dL, and 86.1% had solid tumors.
In the IP, 73.0% of 115 subjects achieved hematopoietic response (2 g/dL Hb increase from baseline or Hb 12 g/dL); 63.5% of subjects who achieved Hb 12 g/dL entered the MP after a median of 6.0 weeks in the IP, and they spent a mean of 9.8 weeks in the MP.
Results show that 74.0% of these 73 subjects maintained an average Hb between 11.0 and 12.5 g/dL over the course of the MP; 87.7% maintained an average Hb of 11.0 to 13.0 g/dL in the MP. The investigators withdrew 34.2% of subjects from the MP because Hb decreased to < 11 g/dL.
From the 115 patients dosed in the IP, 26.1% achieved reduced dosing and 27.0% had doses held. From the 73 patients dosed in the maintenance phase, 7.8% achieved reduced dosing and 13.9% had doses held.
The authors concluded that, "Although 60,000 U QW was used during the IP to achieve a HR, 40,000 U QW is the recommended initiation dose of epoetin alfa."
"This study suggests that epoetin alfa 80,000 U administered every 3 weeks to patients on a [chemotherapy every 3 weeks] regimen is an effective option for maintenance therapy of [chemotherapy]-induced anemia," Dr. Montoya said.
"This is a preliminary study, but we are moving ahead to try to optimize the adequate dosing for our patients," he added.
The study was supported by Ortho Biotech.
[Presentation title: Maintenance Dosing With Epoetin Alfa Every Three Weeks (Q3W) in Anemic Patients With Cancer Receiving Chemotherapy Every Three Weeks: Final Results. Abstract 3555]
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