MRD-2 in the GHSG HD21 trial assessed by a validated circulating tumor DNA sequencing assay

ABSTRACT: Beyond cure, major goals in patients with Hodgkin lymphoma (HL) are tailoring treatment to a patient's individual risk for relapse to reduce acute and late toxicities, identifying candidates for early incorporation of novel agents, and making treatment affordable on a global level. Minimal residual disease (MRD) assessment by circulating tumor DNA (ctDNA) sequencing emerged as a promising strategy to achieve these goals; however, previous studies differed in sampling time points, assay validation, and definitions for MRD negativity. Here, we applied LymphoVista, a validated ctDNA sequencing assay for genotyping and MRD monitoring in lymphoma, to samples obtained from the German Hodgkin Study Group (GHSG) HD21 trial after 2 cycles of treatment (MRD-2) using a case-cohort design. Patients with positive MRD-2 result were at higher risk for relapse, progression, or death compared with MRD-2-negative patients (4-year progression-free survival [PFS], 36.7% vs 82.2%; hazard ratio, 5.3; 95% confidence interval, 2.0-13.8; P = .0008). After inverse probability weighting accounting for the number of events in the full reference set, patients with positive and negative MRD-2 results had 4-year PFS rates of 72.2% vs 95.3%. Combining MRD-2 with positron emission tomography after 2 cycles of BrECADD/eBEACOPP (PET-2) can identify patients at very low and patients at very high risk of relapse, progression, or death. In summary, these results suggest that MRD-2 assessment by LymphoVista allows for early outcome prognostication in patients with HL and could be used as a tool to improve treatment guidance on its own or in conjunction with PET-2.