Long-term follow-up of patients with moderate aplastic anemia and pure red cell aplasia treated with daclizumab.
BACKGROUND
Pure red cell aplasia and moderate aplastic anemia are marrow failure states with an immune pathogenesis. Previously, we described short-term improvements in blood counts in two pilot studies treating moderate aplastic anemia (mAA) and pure red cell aplasia (PRCA) patients with daclizumab, a humanized monoclonal antibody to the interleukin-2 receptor; we now report our long-term experience with a larger cohort of patients.


METHODS
After a median follow-up period of 4.8 years, 19 of 45 (42%) evaluable mAA patients and 10 of 26 (38%) patients with PRCA responded by three months and 2 additional mAA patients responded by six months following administration of the drug.


RESULTS
Seven of 28 (25%) mAA patients achieved long-term packed red blood cell PRBC transfusion independence, and all PRCA responders achieved long-term transfusion PRBC transfusion independence.


CONCLUSIONS
Red cell transfusion-independence prior to treatment in mAA patients predicted response. The only significant adverse treatment-related events were transient rashes and arthralgias. Daclizumab is safe and effective, and produces lengthy remissions in patients with PRCA and mAA.
Sloand
Elaine M
EM
National Heart Lung and Blood Instititute, NIH, Bethesda, MD 20892, USA. sloande@nih.gov
Olnes
Matthew J
MJ
Weinstein
Barbara
B
Wu
Colin
C
Maciejewski
Jaroslaw
J
Scheinberg
Phillip
P
Young
Neal S
NS
D000741:Anemia, Aplastic / Q000188:drug therapy*; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D000077561:Daclizumab; D005500:Follow-Up Studies; D006801:Humans; D007074:Immunoglobulin G / Q000627:therapeutic use*; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D053645:Interleukin-2 Receptor alpha Subunit / Q000037:antagonists & inhibitors; D012010:Red-Cell Aplasia, Pure / Q000188:drug therapy*; D012449:Safety; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; C508017:IL2RA protein, human; D007074:Immunoglobulin G; D007166:Immunosuppressive Agents; D053645:Interleukin-2 Receptor alpha Subunit; D000077561:Daclizumab