Analysis Finds First-Line Practice Patterns in WM Have Shifted Significantly Since 2006

Since 2006, clinicians treating Waldenstrom macroglobulinemia (WM) have shifted away from using chlorambucil as first-line therapy to choosing bortezomib/dexamethasone with or without rituximab (BDR), bendamustine with or without rituximab (BR), and most recently ibrutinib, according to a study presented at the 62nd American Society of Hematology Annual Meeting & Exposition.

The study, presented by Ahmad Halwani, MD, of the George E. Wahlen Veterans Health Administration in Salt Lake City, was an analysis of changing practice patterns recorded in Veteran Affairs electronic health record data. Dr. Halwani and colleagues identified 505 veterans who received a diagnosis of WM and were prescribed first-line treatment for their disease between 2006 and 2018. These patients were followed until loss to follow up, death, or the end of the study period.

A total of 318 patients identified in the study received a first-line treatment for WM between 2006 and 2018. The median time from WM diagnosis to treatment was 1.3 months (95% confidence interval [CI], 0.5-5.0). Overall, the median age of the patient population was 69.9 years, with the majority (73%) aged 65 years or older.

First-line treatment practice patterns significantly shifted over the observation period. Patterns included de-adoption of chemotherapy and increased adoption of BDR, BR, and ibrutinib.

The median immunoglobulin M was lower in patients who were treated with ibrutinib and single-agent rituximab compared with patients treated with chlorambucil with or without rituximab and BDR. The median follow-up duration was 44 months (range, 1-147 months) for all patients; however, patients treated with ibrutinib or BR had shorter follow-up periods (18 and 23 months, respectively).

For all patients with WM, the median unadjusted progression-free survival was 44 months (95% CI, 37-58). The median unadjusted overall survival for this population was 94 months (95% CI, 82-117).

The investigators concluded that additional research is needed “to establish the long-term benefits and potential treatment-related toxicities of WM treatments in real-world clinical settings,” particularly treatments that have only recently been approved/adopted for managing WM.