Long-term results of the Polish Adult Leukemia Group PALG-CLL2 phase III randomized study comparing cladribine-based combinations in chronic lymphocytic leukemia

Abstract

Long-term outcomes following newer therapies for chronic lymphocytic leukemia (CLL) have rarely been reported. This article presents the results of the final analysis of the Polish Adult Leukemia Group PALG-CLL2 study performed 10 years from final patient enrollment. With the extended follow-up time, it was found that cladribine (2-CdA)-based combinations CMC (2-CdA, cyclophosphamide, mitoxantrone) and CC (2-CdA, cyclophosphamide) administered as first-line treatment of progressive CLL resulted in significantly longer progression-free survival, but similar overall survival compared to 2-CdA monotherapy. Furthermore, the risk of potentially fatal late adverse events including infections, autoimmune complications and, particularly, secondary neoplasms was comparable among patients treated with CMC, CC or 2-CdA. The results of our analysis support the importance of long-term outcome monitoring of randomized trials in CLL.

Keywords::

• Chronic lymphocytic leukemia
• CLL
• cladribine
• AIHA
• secondary cancers

Acknowledgements

We thank Professor Andrzej Tukiendorf (Radiotherapy Department, Center of Oncology, Maria Sklodowska-Curie Memorial Institute, Gliwice, Poland) for statistical advice.

The preliminary results of this study were presented at the 52nd Annual Meeting of the American Society of Hematology, San Diego, California, 9–12 December 2011.

Potential conflict of interest

Disclosure forms provided by the authors are available with the full text of this article at www.informahealthcare.com/lal.

This work was supported in part by grants from KBN Warsaw, Poland (No. 4P05B0271), from the Medical University of Lodz (No. 503–1093-1) and by the Foundation for the Development of Diagnostics and Therapy, Warsaw, Poland.