Phase II multicenter study of human CD52 antibody in previously treated chronic lymphocytic leukemia. European Study Group of CAMPATH-1H Treatment in Chronic Lymphocytic Leukemia.
OBJECTIVE
CAMPATH-1H is a human immunoglobulin G1 (IgG1) anti-CD52 monoclonal antibody (MAb) that binds to nearly all B- and T-cell lymphomas and leukemias. We report the results of a multicenter phase II trial that used CAMPATH-1H in previously chemotherapy-treated patients with chronic lymphocytic leukemia (CLL).


METHODS
Twenty-nine patients who had relapsed after an initial response (n = 8) or were refractory (n = 21) to chemotherapy were treated with CAMPATH-1H administered as a 30-mg 2-hour intravenous (IV) infusion thrice weekly for a maximum period of 12 weeks.


RESULTS
Eleven patients (38%) achieved a partial remission (PR) and one (4%) a complete remission (CR) (response rate, 42%; 95% confidence interval [CI], 23% to 61%). Three of eight patients (38%) with a relapse and nine of 21 refractory patients (43%) responded to CAMPATH-1H therapy. CLL cells were rapidly eliminated from blood in 28 of 29 patients (97%). CR in the bone marrow was obtained in 36% and splenomegaly resolved completely in 32%. Lymphadenopathy was normalized in only two patients (7%). The median response duration was 12 months (range, 6 to 25+). World Health Organization (WHO) grade IV neutropenia and thrombocytopenia developed in three (10%) and two patients (7%), respectively. Neutropenia and thrombocytopenia recovered in most responding patients during continued CAMPATH-1H treatment. Lymphopenia (< 0.5 x 10(9)/L) occurred in all patients. Two patients had opportunistic infections and four had bacterial septicemia.


CONCLUSIONS
CAMPATH-1H had significant activity in patients with advanced and chemotherapy-resistant CLL. The most pronounced effects were noted in blood, bone marrow, and spleen. Preferential clearance of blood may allow harvesting of uncontaminated blood stem cells for use in high-dose chemotherapy protocols.
Osterborg
A
A
Department of Oncology (Radiumhemmet), Karolinska Hospital, Stockholm, Sweden. aob@rah.Ks.se
Dyer
M J
MJ
Bunjes
D
D
Pangalis
G A
GA
Bastion
Y
Y
Catovsky
D
D
Mellstedt
H
H
D000328:Adult; D000368:Aged; D000074323:Alemtuzumab; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D000912:Antibodies, Neoplasm / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D015703:Antigens, CD / Q000276:immunology*; D000951:Antigens, Neoplasm; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001792:Blood Platelets; D000074301:CD52 Antigen; D005060:Europe; D006023:Glycoproteins; D006801:Humans; D007700:Kinetics; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000276:immunology* / Q000628:therapy*; D008214:Lymphocytes; D008875:Middle Aged; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000912:Antibodies, Neoplasm; D015703:Antigens, CD; D000951:Antigens, Neoplasm; D000970:Antineoplastic Agents; D000074301:CD52 Antigen; C000613862:CD52 protein, human; D006023:Glycoproteins; D000074323:Alemtuzumab