Mitchell R. Smith, MD, PhD, professor of medicine, George Washington University, associate center director for clinical investigations, Division of Hematology and Oncology, GW Cancer Center, discusses the use of venetoclax (Venclexta) versus ibrutinib (Imbruvica) in patients with chronic lymphocytic leukemia (CLL).

Venetoclax differs from ibrutinib in that it kills cancer cells rather than ceasing cell growth, explains Smith. Moreover, deeper responses have been reported with the BCL-2 inhibitor, leading to higher rates of minimal residual disease negativity (MRD), and potentially, treatment discontinuation.

If patients achieve MRD negativity after receiving venetoclax as a single agent, in combination with ibrutinib, or a CD20 inhibitor, they could potentially discontinue treatment, says Smith. Those trials are planned, and investigators are eager to see what the results will be. Early data suggest that a significant number of patients who achieve MRD negativity can stop treatment for a period of time rather than remaining on ibrutinib indefinitely, Smith says.

This may open the door to time-limited therapy, concludes Smith.