Phase I study of bortezomib in refractory or relapsed acute leukemias.
Bortezomib (Velcade, formerly PS-341) is proteasome inhibitor with documented antitumor activity in multiple myeloma and other lymphoid malignancies. We performed a Phase I study to investigate the maximum tolerated dose and dose-limiting toxicity of bortezomib in patients with acute leukemias refractory to or relapsing after prior therapy. Fifteen patients were treated with 0.75 (n = 3), 1.25 (n = 7), or 1.5 (n = 5) mg/m(2) bortezomib administered twice weekly for 4 weeks every 6 weeks. Dose-limiting toxicity included orthostatic hypotension (n = 2), nausea (n = 2), diarrhea (n = 1), and fluid retention (n = 1), all at 1.5 mg/m(2) bortezomib. Proteasome inhibition was dose dependent and reached 68% at 1.5 mg/m(2) bortezomib. Peak inhibition was observed 1 h after treatment and returned to near baseline levels by 72 h after treatment. Incubation of blast cells with bortezomib in vitro showed induction of apoptosis in three of five patients investigated. We conclude that the maximum tolerated dose of bortezomib in patients with acute leukemia is 1.25 mg/m(2), using a twice-weekly for 4 weeks every 6 weeks schedule. The in vitro evidence of antileukemia and transient hematological improvements observed in some patients warrants further investigation of bortezomib in acute leukemias, probably in combination with other agents.
Cortes
Jorge
J
Department of Leukemia, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA. jcortes@mdanderson.org
Thomas
Deborah
D
Koller
Charles
C
Giles
Francis
F
Estey
Elihu
E
Faderl
Stefan
S
Garcia-Manero
Guillermo
G
McConkey
David
D
Ruiz
Stacey L
SL
Patel
Gira
G
Guerciolini
Roberto
R
Wright
John
J
Kantarjian
Hagop
H
D000293:Adolescent; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis; D001897:Boronic Acids / Q000627:therapeutic use*; D000069286:Bortezomib; D004305:Dose-Response Relationship, Drug; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000188:drug therapy*; D020714:Maximum Tolerated Dose; D008875:Middle Aged; D008956:Models, Chemical; D009190:Myelodysplastic Syndromes / Q000188:drug therapy*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D061988:Proteasome Inhibitors; D011719:Pyrazines / Q000627:therapeutic use*; D012008:Recurrence; D013997:Time Factors
D000970:Antineoplastic Agents; D001897:Boronic Acids; D061988:Proteasome Inhibitors; D011719:Pyrazines; D000069286:Bortezomib; D046988:Proteasome Endopeptidase Complex