Dr. Fenske Discusses Disease Progression on Ibrutinib in MCL

Timothy Fenske, MD, MS, an associate professor at the Medical College of Wisconsin, discusses his recommendations for oncologists treating patients with mantle cell lymphoma (MCL) who are progressing on ibrutinib (Imbruvica).

If patients appear to be progressing on ibrutinib, it is necessary to establish whether they are truly progressing on the BTK inhibitor or whether they are intolerant to the medication, says Fenske.

Sometimes, the drug will be stopped due to adverse events. For example, if a patient is experiencing atrial fibrillation, renal insufficiency, diarrhea, rash, or some of the more musculoskeletal complaints to ibrutinib, but they are still responding to it, then a switch to the other FDA-approved BTK inhibitor acalabrutinib (Calquence) should be considered.

However, if the patient’s lymphoma is progressing even though they’ve been compliant, there is no evidence to suggest that acalabrutinib would be effective in that setting, explains Fenske. Some of the data regarding newer-generation BTK inhibitors may have the potential to overcome resistance. For now, off-protocol, the recommended approach is to switch to a different class of drug, such as lenalidomide (Revlimid), or a proteasome inhibitor. Otherwise, patients may be able to receive venetoclax (Venclexta) off-label or enroll in a clinical trial, concludes Fenske.