Adding Epcoritamab to First-Line Lymphoma Treatment Reduces Risk of Progression or Death by 51% in Phase 3 Trial

For fast-growing diffuse large B-cell lymphoma (DLBCL), whether first-line treatment can keep the disease under control shapes patients’ subsequent treatment paths. On October 5, AbbVie and Genmab announced interim results from the phase 3 EPCORE DLBCL-2 trial: adding the bispecific antibody epcoritamab to R-CHOP immunochemotherapy significantly improved progression-free survival, providing new evidence of efficacy in initial treatment.

The primary endpoint focused on patients with International Prognostic Index (IPI) scores of 3 to 5, who have a higher prognostic risk. Compared with the control regimen, the combination reduced the risk of disease progression or death by 51%, with a hazard ratio of 0.49 and a 95% confidence interval of 0.35 to 0.69. The key secondary endpoint, covering all patients with IPI scores of 2 to 5, yielded the same hazard ratio. Results in the two populations were consistent in direction, but the distinct roles of the primary and secondary analyses must still be kept clear.

The “51% reduction” describes the relative risk of progression or death during follow-up. It does not mean that 51% more patients were cured, nor can it be directly converted into a gain in life expectancy. Progression-free survival measures the time during which the disease has not progressed and the patient remains alive. The announcement has not yet provided the full survival curves and follow-up data needed to assess the absolute benefit, and an overall survival benefit has not yet been demonstrated.

Epcoritamab is administered by subcutaneous injection. One end binds to CD3 on T cells, while the other binds to CD20 on B cells, bringing T cells close to cells bearing CD20 so they can attack them. Patients in the trial were randomized in a two-to-one ratio: the experimental group received six cycles of epcoritamab plus R-CHOP, followed by two cycles of epcoritamab; the control group received six cycles of R-CHOP, followed by two cycles of rituximab. The study therefore compares two complete, fixed treatment regimens.

OncLive’s coverage of the same announcement further noted that the primary endpoint was assessed by an independent review committee using the Lugano 2014 criteria. Eligible patients were 18 to 79 years old and had ECOG performance status scores of 0 to 2, with patients who had an IPI score of 2 capped at approximately 30% of total enrollment. These criteria help define the scope of the evidence: the results cannot be directly generalized to all patients aged 80 or older, those with poorer performance status, or those with lower IPI scores.

Safety remains an important gap pending the full report. The companies said the combination’s safety profile was consistent with the known profiles of the individual drugs, but specific adverse event rates have not yet been disclosed. Epcoritamab itself carries risks including cytokine release syndrome, serious infections, and neurotoxicity. Differences in serious side effects, treatment discontinuation, and treatment-related deaths after its addition to first-line therapy will affect the assessment of efficacy and treatment burden.

This was the trial’s first planned interim efficacy analysis, and the independent data monitoring committee recommended unblinding because of the significant benefit. The two companies plan to submit the data to a medical meeting and discuss next steps with regulatory authorities in various regions. Epcoritamab plus R-CHOP remains an investigational combination that has not been approved. These results support further evaluation of its role in first-line treatment, while whether it can change clinical practice still depends on the complete efficacy and safety data and subsequent review.