First-line treatment with fludarabine, cyclophosphamide, and rituximab (FCR) did not appear to offer clinical benefit over bendamustine and rituximab (BR) for patients with chronic lymphocytic leukemia (CLL) who were treated predominantly in the community setting, according to the results of the Connect CLL Registry (ClinicalTrials.gov identifier: NCT01081015). The study results were recently published in Blood Advances.
The prospective observational cohort study included 1494 patients who were enrolled between 2010 and 2014 from 199 treatment sites. Most patients (87.8%) were treated at community hospitals and the remaining were treated at academic institutions (10.4%) or government centers (1.9%).
Patients were categorized by line of therapy at the time of study enrollment, and 59.5% were on their first line of therapy, 17.5% on their second line, and 23.0% on their third or later line. The most common regimens used were bendamustine and rituximab (33.5%); fludarabine, cyclophosphamide, and rituximab (21.4%); and rituximab monotherapy (18.5%).
Patients who received BR as their first line of therapy had a similar event-free survival (EFS) to those who received FCR (59 vs 55 months). A multivariate analysis showed that treatment with BR or FCR was linked to a prolonged EFS (hazard ratio [HR], 0.60; P <.0001) and OS (HS, 0.67; P =.0162) compared with other regimens.
The study authors asserted that the “proven clinical superiority” of FCR over BR was “not replicated in this analysis, suggesting that clinical trial results may not be directly applicable to community practice.”
The analysis also showed that patients who received ibrutinib in the second or later line of therapy had an improved OS compared with those who did not. Specifically, receipt of ibrutinib in the second line of therapy had a HR of 0.279 (P=.009), third line an HR of 0.441 (P=.011), and fourth or later line an HR of 0.578 (P=.043).
“Because the Registry was conducted from 2010 to 2014, no patients received ibrutinib in the frontline setting,” the study authors explained.
Mato A, Nabhan C, Lamanna N, et al. The Connect CLL Registry: Final analysis of 1494 patients with chronic lymphocytic leukemia across 199 US sites. Blood Adv. 2020;4(7):1407-1418.