The phase 3 ECOG-ACRIN EA4151 study (NCT03267433) included 650 patients with mantle cell lymphoma who received ‘any induction’ regimen and were then tested for the presence of clonal markers. Patients who did not have informative markers, defined as ‘MRD indeterminate’, (n=85) and those who were MRD-positive (n=49) were all allocated to receive auto-SCT plus rituximab. Patients with undetectable MRD were randomised 1:1 to auto-SCT plus rituximab (arm A, n=257) or rituximab alone (arm B, n=259). The primary outcome was overall survival (OS).
The 3-year OS rates were 82.1% for arm A and 82.7% for arm B (HR 1.11; 95% CI 0.71–1.74; P=0.66), showing that there was no benefit of auto-SCT in patients with mantle cell lymphoma who achieved undetectable MRD after induction therapy. This finding was consistent across Mantle cell lymphoma International Prognostic Index (MIPI) risk groups and regardless of whether patients had received intensive or non-intensive induction therapy.
“Although the numbers were small, an exploratory analysis displayed that MRD-positive patients who converted to undetectable MRD after auto-SCT (n=17) had better overall survival than those who remained MRD-positive after auto-SCT (OS rate 100% vs 63.6%). This suggests that auto-SCT still has value in patients who are MRD-positive after induction therapy,” argued Dr Timothy Fenske (Medical College of Wisconsin, WI, USA).
“The initial findings of the EA4151 trial indicate that auto-SCT does not benefit patients with mantle cell lymphoma who achieve undetectable MRD after induction therapy,” summarised Dr Fenske. “However, longer follow-up is needed to confirm these findings.”
Medical writing support was provided by Robert van den Heuvel.