Relapsed Primary Central Nervous System Lymphoma

The purpose of this study is to find out whether the combination of epcoritamab and ibrutinib is a safe treatment approach that causes few or mild side effects in people with relapsed/refractory primary central nervous system lymphoma (PCNSL) or secondary central nervous system lymphoma (SCNSL).

This is a multi-center, open-label study to evaluate the safety, pharmacokinetics (PK), and anti-cancer activity of oral administration of emavusertib alone or in combination with ibrutinib in adult participants with relapsed or refractory (R/R) hematologic malignancies. This trial will be completed in four parts. In Part A1, emavusertib will be evaluated first in a dose escalating monotherapy setting to establish the safety and tolerability (complete). In Part A2, emavusertib will be evaluated in combination with ibrutinib at 560 milligrams (mg) once daily (QD) or 420 mg QD as indicated by disease (Part A2 complete). Part B will comprise 2 cohorts to assess safety and efficacy of emavusertib in combination with ibrutinib in participants with R/R primary central nervous system lymphoma (PCNSL) who have directly progressed on a bruton tyrosine kinase inhibitor (BTKi). In this part of the study, emavusertib will be dosed at 100 mg or 200 mg twice daily (BID) in combination with ibrutinib in 28-day treatment cycles. Part C will comprise 3 treatment arms in the second-line setting to assess the efficacy and safety of emavusertib monotherapy, ibrutinib monotherapy, and emavusertib in combination with ibrutinib in participants with R/R PCNSL who are naïve to BTKi treatment. In this part of the study, eligible second-line participants with R/R PCNSL who are naïve to BTKi treatment will be randomized 1:1:1 to 1 of 3 treatment arms: (1) emavusertib 200 mg BID, (2) ibrutinib 560 mg QD, or (3) emavusertib 200 mg BID in combination with ibrutinib 560 mg QD.