The reason a patient with chronic lymphocytic leukemia (CLL) discontinues ibrutinib directly affects survival, and those who discontinue for disease transformation have particularly poor survival, according to a study published in Cancer.1

Ibrutinib, a Bruton tyrosine kinase inhibitor, is approved for the treatment in both CLL frontline and relapsed/refractory settings. Although previous research demonstrated poor outcomes for patients who discontinued ibrutinib, long-term outcomes were unclear.

Investigators retrospectively analyzed data from 320 patients who received ibrutinib as part of clinical trials conducted at The University of Texas MD Anderson Cancer Center in Houston between 2010 and 2015.

Of those, 28% discontinued ibrutinib, including 80 patients with relapsed/refractory disease and 10 with newly diagnosed disease. Median time to ibrutinib discontinuation was 15 months.

Thirty-two percent discontinued ibrutinib for intolerance, 21% for progression, 10% for Richter transformation, and 31% for miscellaneous reasons.

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Forty-four percent of the 90 patients who discontinued ibrutinib were alive after a median follow-up of 38 months post-ibrutinib initiation. Median survival was 33 months for patients who discontinued ibrutinib due to intolerance, 16 months for progressive CLL, 2 months for disease transformation, and 11 months for miscellaneous reasons.

About 40% of the 19 patients who discontinued ibrutinib for progressive disease responded to subsequent therapy, suggesting a need for effective salvage strategies.

Reference

  1. Jain P, Thompson PA, Keating M, et al. Long-term outcomes for patients with chronic lymphocytic leukemia who discontinue ibrutinib. Cancer. 2017 Feb 7. doi: 10.1002/cncr.30596 [Epub ahead of print]