MRD Status Predicts Outcomes in Patients With Previously Untreated FL

Minimal residual disease (MRD) status can predict outcome after induction and during maintenance in previously untreated patients with follicular lymphoma (FL), according to research published in the Journal of Clinical Oncology.

The findings are from a prospective analysis of the randomized, multicenter phase 3 GALLIUM study, which previously evaluated the efficacy and safety of obinutuzumab (G) or rituximab (R) in combination with chemotherapy as induction and maintenance in 1202 previously untreated patients with FL (ClinicalTrials.gov Identifier: NCT01332968).

“G plus chemotherapy (G-chemo) significantly improved investigator-assessed progression-free survival (PFS) compared with R plus chemotherapy,” the authors explained in their report.

In the preplanned MRD assessment, MRD status (at a sensitivity of 10^-5) was evaluated at predefined time points (mid-induction [MI] in peripheral blood [PB], end of induction [EOI] in pooled PB and bone marrow [BM], and at 4-6 monthly intervals during maintenance and follow-up in PB). In patients with evaluable biomarker data at diagnosis, the association between MRD status and PFS and overall survival (OS) was assessed.

Patients who were MRD-positive had inferior PFS at MI (hazard ratio [HR], 3.03; 95% CI, 2.07-4.45; P <.0001) and EOI (HR, 2.25; 95% CI, 1.53-3.32; P <.0001). Patients with late responses (MRD-positive at MI/MRD-negative at EOI) had a significantly poorer PFS than those with early responses (MRD-negative at MI/MRD-negative at EOI; HR, 3.11; 95% CI, 1.75-5.52; P =.00011). 

In patients treated with G-chemo vs R-chemo, MRD response was significantly higher at MI (94.2% vs 88.9%; P =.013) and EOI (93.1% vs 86.7%; P =.0077). 

During the maintenance period, MRD positivity was found more frequently among patients treated with R-chemo than those treated with G-chemo (R/G-CHOP, 20.7% vs 7.0%; R/G-CVP, 21.7% vs 9.4%), and MRD positivity was associated with clinical relapse.

“In conclusion, this analysis demonstrates that early and continuous MRD response after immunochemotherapy in first-line treatment is the most important factor for long-term disease control and outcomes in FL and confirms the prognostic value of MRD status at EOI and throughout maintenance,” the authors wrote in their report. 

Disclosure: This research was supported by F. Hoffmann-La Roche Ltd. Please see the original reference for a full list of disclosures.

This article originally appeared on Hematology Advisor