Epcoritamab (epcor) + chemoimmunotherapy (CIT) in patients (pts) with relapsed/refractory large B-cell lymphoma (R/R LBCL) eligible for autologous stem cell transplant (ASCT): Pooled results from arms 4 and 10 of EPCORE NHL-2.

7061 Background: Pts with R/R LBCL can have inadequate response to salvage treatment (tx), precluding ASCT. While CAR T therapies are standard of care in the 2L setting for pts with early relapse (< 12 mo of 1L tx), their use is limited by eligibility, accessibility, or cost. Regimens that enhance salvage tx response rates enabling pts to proceed to ASCT are needed. In Arms 4 and 10 of the phase 1b/2 EPCORE NHL-2 trial (NCT04663347), epcor + CIT showed high response rates in ASCT-eligible R/R LBCL. A pooled analysis of these data is reported. Methods: ASCT-eligible pts received epcor + rituximab, dexamethasone, cytarabine, and oxaliplatin/carboplatin (R-DHAX/C) (Arm 4) or epcor + rituximab, ifosfamide, carboplatin, and etoposide (R-ICE) (Arm 10). After salvage tx, pts could proceed to ASCT or remain on epcor mono tx. ORR per investigator, DOCR, PFS, OS, and safety are reported. Results: The analysis included 63 pts (Arm 4: n = 29; Arm 10: n = 34). Baseline characteristics: median age 61 y (range 28–77), 68% male, 71% stage III/IV, 13% (8/33 assessed) high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 translocations (central lab), 8% prior CAR T. 79% (n = 50) were receiving 2L tx; 57% (n = 36) were receiving 2L tx and were refractory or had early relapse to 1L tx. Median relative CIT dose intensity was ≥ 80%. At 18.3 mo median follow-up, ORR and CR rates were 84% and 67% (Table). 57% (n = 36) proceeded to ASCT; 16% (n = 10) remained on epcor mono tx due to pt/physician decision. Median DOCR, PFS, and OS were not reached in pts who proceeded to ASCT or who remained on epcor. Similar outcomes were seen in 2L pts and across 2L pts with early and late relapse. Overall, the most common any-grade TEAEs were anemia (68%), thrombocytopenia (68%), and neutropenia (62%). CRS occurred in 48% of pts and ICANS in 3%; all events were grade 1–2. Serious infections occurred in 17%. TEAEs led to tx discontinuation in 11%. There were no fatal TEAEs. Conclusions: In this pooled analysis of ASCT-eligible pts with R/R LBCL, tx with epcor + salvage CIT resulted in high CR rates, enabling a large proportion of pts to proceed to ASCT. Deep, durable responses were seen in pts who underwent ASCT and those who continued epcor mono tx. A high CR rate was also observed in 2L pts with early relapse. Safety was consistent with prior reports. Dose intensity of CIT was not impacted. These findings support epcor-based combination salvage strategies to increase response depth and facilitate higher ASCT rates and possible cure in ASCT-eligible pts with DLBCL. Clinical trial information: NCT04663347 . All pts(N = 63) 2L(n = 50) 2L with early relapse a (n = 36) Proceeded to ASCT(n = 36) Remained on epcor mono(n = 10) ORR/CR, % 84/67 84/68 81/61 100/94 100/80 DOCR, 18-mo rate, % 79 80 81 83 64 PFS, 18-mo rate, % 62 62 58 80 67 OS, 18-mo rate, % 82 82 77 93 100 a Pts receiving 2L tx who were refractory to or progressed <12 mo of 1L tx.