Chronic lymphocytic leukemia is the most common form of leukemia in adults, affecting primarily older patients with a median diagnosis age of around 70. For decades, treatment has relied on a combination of chemotherapy and immunotherapy drugs that, while effective, carry a significant side effect burden and require frequent clinic visits. A landmark clinical trial published in The New England Journal of Medicine now offers compelling evidence that a targeted oral therapy is significantly more effective and better tolerated, and should replace the current standard of care.
At FOMAT, hematology and oncology trials are among the most impactful work we do, particularly for older patients who often face limited treatment options and substantial toxicity from standard chemotherapy regimens. Studies like this one represent exactly the kind of evidence that changes clinical practice and improves quality of life for patients living with chronic lymphocytic leukemia.
How Ibrutinib Compares to Standard Chronic Lymphocytic Leukemia Treatment
The trial enrolled 547 patients with chronic lymphocytic leukemia at 219 centers across the United States and Canada. All participants were older than 65, with a median age of 71, and 67 percent were male. Patients were randomly assigned to one of three treatment regimens: the standard combination of bendamustine and rituximab, ibrutinib alone, or ibrutinib combined with rituximab.
After two years, 87 percent of patients receiving ibrutinib alone were alive without disease progression, compared to 74 percent of those on the standard bendamustine plus rituximab regimen. There was no statistically significant difference between patients receiving ibrutinib alone and those receiving ibrutinib combined with rituximab, suggesting that the addition of rituximab provides no meaningful benefit over ibrutinib monotherapy.
Why Ibrutinib Represents a New Standard for Chronic Lymphocytic Leukemia
Ibrutinib works by targeting cancer cells directly without damaging healthy cells, which is the mechanism behind its more favorable side effect profile compared to traditional chemotherapy. The drug is taken as a single pill once daily, a substantial practical advantage over the standard regimen, which requires patients to come in for infusions three times per month plus an injection.
Approximately 17 percent of patients receiving ibrutinib alone experienced atrial fibrillation, an irregular heartbeat, which remains a known risk associated with the drug. However, the overall side effect burden was lower than that observed with bendamustine plus rituximab, according to study co author Scott Smith, MD, PhD, professor of hematology and oncology at Loyola Medicine and Loyola University Chicago Stritch School of Medicine.
The U.S. Food and Drug Administration approved ibrutinib, marketed under the brand name Imbruvica, for the treatment of chronic lymphocytic leukemia in 2016. This trial provides strong prospective evidence supporting its use as the preferred first line therapy in elderly patients.
What Comes Next in Chronic Lymphocytic Leukemia Research
The study was coordinated by the Alliance for Clinical Trials in Oncology, with Dr. Smith serving as executive officer and responsible for overall study execution. Additional trials evaluating ibrutinib in chronic lymphocytic leukemia patients under the age of 65 are currently underway, which will help determine whether the same benefits extend to younger populations and inform treatment guidelines across a broader patient demographic.
For patients and families navigating a chronic lymphocytic leukemia diagnosis, participation in clinical research offers access to emerging therapies and contributes to the evidence base that shapes future treatment standards.
FOMAT conducts hematology and oncology clinical trials at sites across the United States. To explore active studies, visit FOMAT’s patient studies page.
For the full source, see the original publication in The New England Journal of Medicine.