PURPOSE: To conduct a phase II trial in chemoresistant hairy cell leukemia (HCL) with BL22, a recombinant anti-CD22 immunotoxin which showed phase I activity in HCL. PATIENTS AND METHODS: Eligible patients had relapsed/refractory HCL and needed treatment based on blood counts. Patients were stratified into three groups: response to cladribine less than 1 year, those with a response lasting 1 to 4 years, or no response and uncontrolled infection. Patients received BL22 40 microg/kg every other day for three doses on cycle 1. Those achieving hematologic remission (HR), defined as neutrophils > or = 1,500/mm(3), hemoglobin > or = 11 g/dL, and platelets > or = 100,000/mm(3), were observed. Patients without HR were re-treated at 30 microg/kg every other day for three doses every 4 weeks beginning at least 8 weeks after cycle 1. RESULTS: Thirty-six patients were enrolled including 26, nine, and one in groups 1 to 3. The response after one cycle (CR, 25%; PR, 25%) improved when 56% were re-treated (CR, 47%; PR, 25%). CR rate was similar in groups 1 and 2 (P = .7). Twenty-two with baseline spleen height lower than 200 mm had higher CR (64% v 21%; P = .019) and OR rates (95% v 36%; P = .0002) compared to 14 with spleens either absent or higher than 200 mm. The only serious toxicity was reversible grade 3 hemolytic uremic syndrome, not requiring plasmapheresis, in two patients (6%). High neutralizing antibodies were observed in four patients (11%) and prevented re-treatment. CONCLUSION: BL22 activity in HCL is confirmed. Best responses to BL22 after cladribine failure are achieved before the patients develop massive splenomegaly or undergo splenectomy.
PURPOSE: To conduct a phase II trial in chemoresistant hairy cell leukemia (HCL) with BL22, a recombinant anti-CD22 immunotoxin which showed phase I activity in HCL. PATIENTS AND METHODS: Eligible patients had relapsed/refractory HCL and needed treatment based on blood counts. Patients were stratified into three groups: response to cladribine less than 1 year, those with a response lasting 1 to 4 years, or no response and uncontrolled infection. Patients received BL22 40 microg/kg every other day for three doses on cycle 1. Those achieving hematologic remission (HR), defined as neutrophils > or = 1,500/mm(3), hemoglobin > or = 11 g/dL, and platelets > or = 100,000/mm(3), were observed. Patients without HR were re-treated at 30 microg/kg every other day for three doses every 4 weeks beginning at least 8 weeks after cycle 1. RESULTS: Thirty-six patients were enrolled including 26, nine, and one in groups 1 to 3. The response after one cycle (CR, 25%; PR, 25%) improved when 56% were re-treated (CR, 47%; PR, 25%). CR rate was similar in groups 1 and 2 (P = .7). Twenty-two with baseline spleen height lower than 200 mm had higher CR (64% v 21%; P = .019) and OR rates (95% v 36%; P = .0002) compared to 14 with spleens either absent or higher than 200 mm. The only serious toxicity was reversible grade 3 hemolytic uremic syndrome, not requiring plasmapheresis, in two patients (6%). High neutralizing antibodies were observed in four patients (11%) and prevented re-treatment. CONCLUSION: BL22 activity in HCL is confirmed. Best responses to BL22 after cladribine failure are achieved before the patients develop massive splenomegaly or undergo splenectomy.
Authors: R J Kreitman; I Margulies; M Stetler-Stevenson; Q C Wang; D J FitzGerald; I Pastan Journal: Clin Cancer Res Date: 2000-04 Impact factor: 12.531
Authors: R J Kreitman; W H Wilson; K Bergeron; M Raggio; M Stetler-Stevenson; D J FitzGerald; I Pastan Journal: N Engl J Med Date: 2001-07-26 Impact factor: 91.245
Authors: F Lauria; M Lenoci; L Annino; D Raspadori; G Marotta; M Bocchia; F Forconi; S Gentili; M La Manda; S Marconcini; M Tozzi; L Baldini; P L Zinzani; R Foà Journal: Haematologica Date: 2001-10 Impact factor: 9.941
Authors: Deborah A Thomas; Susan O'Brien; Carlos Bueso-Ramos; Stefan Faderl; Michael J Keating; Francis J Giles; Jorge Cortes; Hagop M Kantarjian Journal: Blood Date: 2003-06-19 Impact factor: 22.113