Dr. Wierda on Ibrutinib Resistance in CLL

William G. Wierda, MD, PhD, medical director, Leukemia Center, The University of Texas MD Anderson Cancer Center, discusses resistance to ibrutinib in patients with chronic lymphocytic leukemia (CLL).

Not many patients are resistant to ibrutinib, Wierda explains. However, approximately 30-40% of patients who develop resistance have Richter’s transformation, and will likely require more aggressive treatment. Other patients may discontinue treatment due to toxicity.

However, BTK and PLCG2 mutations can occur, which render resistance to ibrutinib. Regarding standard clinical use of the drug, Wierda says there is no need to monitor for these mutations nor adjust treatment for it, though data should be collected.