PFS is defined as the duration from the date of randomization to the date of disease progression determined per Lugano 2014 criteria as assessed by an independent review committee (IRC), or death, whichever occurs first.

Cytokine Release Syndrome events will be graded using American Society for Transplantation and Cellular Therapy (ASTCT), with a higher grade indicating higher severity.

ICANS events will be graded using ASTCT, with a higher grade indicating higher severity.

Ntox is defined as the percentage of participants who developed at least 1 Grade 3 or higher Ntox since the initiation of epcoritamab treatment.

DLT events are defined as clinically significant adverse events (AEs) or abnormal laboratory values assessed as unrelated to disease progression, underlying disease, intercurrent illness, or concomitant medications as assessed per Common Terminology Criteria for Adverse Events (NCI-CTCAE) criteria version 5.0.

An AE is any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product and that does not necessarily have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign. (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal (investigational) product, whether or not related to the medicinal (investigational) product.

ORR is defined as the percentage of participants achieving complete response (CR) or partial response (PR) based on Lugano criteria.