New Agents for Relapsed or Resistant CLL
In February 2014 the FDA approved ibrutinib, an inhibitor of Bruton’s tyrosine kinase, which plays a key role in the growth and division of lymphoid cells. In patients with relapsed or refractory CLL or small lymphocytic lymphoma, treatment with ibrutinib significantly improved progression-free survival and overall survival compared with ofatumumab.3
At 12 months, the overall survival rate was 90% in the ibrutinib group and 81% in the ofatumumab group. Ibrutinib was generally well-tolerated.
Another targeted drug, idelalisib, received FDA approval for use in combination with rituximab for patients with relapsed CLL for whom rituximab or standard chemotherapy alone would not be appropriate because of concomitant medical conditions.
In a randomized study, patients with CLL who had decreased renal function, previous therapy-induced myelosuppression, or major coexisting illnesses were randomly assigned to receive rituximab plus either idelalisib or placebo.4
Overall survival at 12 months was 92% among patients taking idelalisib and 80% among patients given placebo.
“This has truly been a banner year for CLL and for clinical cancer research as a whole,” said ASCO President Peter P. Yu, MD, FASCO.
“It’s also remarkable that almost one-third of the year’s top studies were made possible by federal research dollars. We cannot underestimate the importance of federal investment for answering critical cancer care questions, particularly in rare, under-studied cancers.”
- Goede V, Fischer K, Busch R, et al. Obinutuzumab plus chlorambucil in patients with CLL and coexisting conditions. New Engl J Med. 2014;370(12):1101-1110.
- ARZERRA® (offatumumab) [package insert]. Research Triangle Park, NC: GlaxoSmithKline; 2014. https://www.gsksource.com/gskprm/htdocs/documents/ARZERRA.PDF
- Byrd JC, Brown JR, O’Brien S, et al. Ibrutinib versus ofatumumab in previously treated chronic lymphoid leukemia. New Engl J Med. 2014;371(3):213-223.
- Furman RR, Sharman JP, Coutre SE, et al. Idelalisib and rituximab in relapsed chronic lymphocytic leukemia. New Engl J Med. 2014;370(11):997-1007.