The COP regimen is not a feasible treatment for advanced, refractory chronic lymphocytic leukemia

The COP regimen has been widely used as a second-line treatment for advanced chronic lymphocytic leukemia (CLL). In this retrospective analysis of COP therapy 24 patients with CLL were included. All but two patients had previously been treated with alkylating agents and had become refractory to the therapy. The overall response rate to COP was 25%. Three patients had CR (12.5%), three PR (12.5%), five SD (21%), four PD (17%), and nine patients died (37.5%) during the COP treatments. The cause of death was neutropenic sepsis in all cases. The median duration of responses was 18 months. The median survival of all patients was 9.5 months. The survival of responders was 24.5 and of non-responders only 5.5 months. The COP regimen seems to have low efficacy in the treatment of refractory CLL and the toxicity of this regimen in the late disease phase appears to be unacceptable.