PURPOSE: T-prolymphocytic leukemia (T-PLL) is an aggressive malignancy of mature 
T cells refractory to conventional chemotherapy, with a median survival duration 
of 7.5 months. We report here promising results with the use of a genetically 
reshaped human CD52 antibody, CAMPATH-1H.
PATIENTS AND METHODS: Fifteen patients with T-PLL, most of whom had received the 
purine analog deoxycoformycin (DCF), were treated with CAMPATH-1H. Results were 
compared with those of 25 patients treated with DCF.
RESULTS: Major responses occurred in 11 patients (73%) treated with CAMPATH-1H 
compared with 40% with DCF. Complete remissions (CRs) were documented in nine 
(60%) of the CAMPATH-1H cases and only three (12%) were obtained with DCF. CRs 
with CAMPATH-1H were durable, and re-treatment with the antibody resulted in 
second CRs in three relapsed patients. Two of them were successfully autografted 
with peripheral-blood and bone marrow stem cells collected during the first CR. 
Apart from first-dose reactions, infusions of CAMPATH-1H were well tolerated. 
However, two responding patients developed severe bone marrow aplasia that was 
fatal in one; the second remained moderately pancytopenic 21 weeks after 
stopping CAMPATH-1H therapy. The cause of this adverse effect is unknown.
CONCLUSION: CAMPATH-1H is an effective agent in T-PLL and represents a 
significant improvement over other types of therapy. However, CAMPATH-1H alone 
is not sufficient for long-term remissions, and the role of autologous stem-cell 
transplantation needs further investigation.