At OncLive’s State of the Science Summit on Hematologic Malignancies, Dr. Richard Furman, director of the Chronic Lymphocytic Leukemia (CLL) Research Center at Weill Cornell Medicine, discussed how medical oncologists should be using prognostic markers to make risk assessments in order to determine individualized treatments for their patients with CLL.
Dr. Furman noted that current CLL therapies are effective, but they often lead to complications. CLL patients treated with standard chemotherapy drug combination fludarabine, cyclophosphamide, rituximab (FCR) are often prone to developing treatment resistance or Richter’s transformations (RT), in which their CLL transforms into a more aggressive diffuse large B-cell lymphoma (DLBCL). They may also succumb to infectious complications, adverse events, or secondary malignancies.
Because of the risks associated with FCR treatment, Dr. Furman suggested a movement toward treatment agents that are not as toxic, such as ibrutinib. But even with ibrutinib, patients can develop resistance to treatment. For example, in cysteine481-to-serine mutations, the amino acid in Bruton’s tyrosine kinase (BTK) that ibrutinib binds to is changed from a cysteine to a serine, prohibiting ibrutinib from continuing to bind. This results in inadequate ibrutinib coverage and enables CLL cells to escape treatment and survive.
According to Dr. Furman, a large number of CLL patients will have excellent responses and enjoy very long progression free survivals. What is important is to identify those who will not and to devise a treatment strategy that can improve their outcomes. Currently, interphase FISH (demonstrating deletion 11q or 17p), NOTCH1 mutation, or certain V genes help identify those patients who will progress on currently novel agents or have a risk of Richter’s transformation. In the future, stimulated karyotyping, or evaluating changes in the chromosomes after stimulation of the CLL cells, will also be of great importance.
The CLL team at Weill Cornell Medicine and NewYork-Presbyterian is currently investigating an early intervention trial in which patients at risk of developing Richter’s transformation or resistance to BTK inhibitors receive intervention before the mutations have a chance to develop. Our team is also looking into the use of combination therapies, such as ibrutinib and venetoclax, in treatment of CLL patients.
Additionally, Dr. Furman pointed out that prognostic markers are dependent upon the setting in which they’re used. Those used for FCR, such as minimal residual disease (MRD), don’t necessarily apply to ibrutinib. He said that prognostic markers are traditionally based upon responses, but we now need to start looking at them from a progression-free survival (PFS) perspective.
To hear more from Dr. Furman about the outlook of CLL prognostic markers, check out this short OncLive clip: