Lay Summary: Purine analogues and the PCR regimen are effective in CLL.
When purine analogs were first introduced in the treatment ofpatients with CLL, the issue of whether or not these agentsshowed cross-resistance was a matter of extensive debate. Thecurrent notion is that cross-resistance does exist. However,pentostatin combined with cyclophosphamide has been reportedto produce responses (77% including one CR) in a small seriesof 13 patients who did not respond to fludarabine-based therapy. A second phase II study was recentlypublished. In fludarabine-refractory patients,75% responded. Toxicity was acceptable, with grade 3/4 infections(including fever of unknown origin) in 28%. The regimen waswell tolerated, with 72% of patients receiving the planned treatmentat full dose.
Mark A. Weiss, Peter G. Maslak, Joseph G. Jurcic, David A. Scheinberg, Timothy B. Aliff, Nicole Lamanna, Stanley R. Frankel, Steven E. Kossman, Denise Horgan , Pentostatin and Cyclophosphamide: An Effective New Regimen in Previously Treated Patients With Chronic Lymphocytic Leukemia Journal of Clinical Oncology, Vol 21, Issue 7 (April), 2003: 1278-1284
N. Lamanna, M. Kalaycio, P. Maslak, J. G. Jurcic, M. Heaney, R. Brentjens, A. D. Zelenetz, D. Horgan, A. Gencarelli, K. S. Panageas, D. A. Scheinberg, and M. A. Weiss
Pentostatin, Cyclophosphamide, and Rituximab Is an Active, Well-Tolerated Regimen for Patients With Previously Treated Chronic Lymphocytic Leukemia
J. Clin. Oncol., April 1, 2006; 24(10): 1575 – 1581.
E. Montserrat, C. Moreno, J. Esteve, A. Urbano-Ispizua, E. Gine, and F. Bosch
How I treat refractory CLL
Blood, February 15, 2006; 107(4): 1276 – 1283.