e19003 Background: Epcoritamab, a CD3×CD20 bispecific antibody approved for R/R DLBCL, is administered SC with inpatient monitoring for 24 h after the first full dose (FFD). Previous report from NHL-6 (NCT05451810) demonstrated feasibility of outpatient dosing and monitoring of epcoritamab in 2L+ DLBCL after FFD, with 92% of patients (pts) monitored outpatient after FFD (Vaidya SOHO 2025 Abstract ABCL-1224). Here we present longer follow-up data. Methods: Pts aged ≥18 y with R/R DLBCL, ECOG PS 0–2, who received ≥1 prior line of therapy (LOT), including immunochemotherapy with anti-CD20 antibody, were enrolled in academic and community centers of US and Puerto Rico. Pts received epcoritamab in 28-day (D) cycles (C): 0.16-mg and 0.8-mg C1 step-up doses, 48-mg full dose C1D15 onward (C1–3, QW; C4–9, Q2W; C≥10, Q4W). Safety education materials and mandatory cytokine release syndrome (CRS) prophylaxes were given in C1. Primary endpoints were grade ≥3 CRS, immune effector cell–associated neurotoxicity syndrome (ICANS), and neurologic events. Secondary endpoints were efficacy and safety. Results: At the 11 Nov 2025 cutoff, 92 pts received ≥1 dose of epcoritamab and the baseline characteristics have been reported previously (Vaidya SOHO 2025 Abstract ABCL-1224). The median number of treatment cycles was 6 (range 1–35). At 17.3-mo median follow-up (95% CI 15.4–18.9), all pts experienced ≥1 treatment-emergent adverse event (TEAE), with 22.8% leading to treatment discontinuation (5.4% DLBCL disease progression reported as TEAE). Grade 3–4 TEAEs occurred in 81.5%, Grade 5 TEAEs in 17.4% of pts (7.6% DLBCL disease progression, 5.4% infections 3.3% COVID-19), and serious adverse events in 65.2%. Infections and infestations were reported in 68.5% of pts, including 26.1% that were serious. The incidence and severity of CRS and ICANS were consistent with prior reports. With extended follow-up, the overall response rate (ORR) and time to response remained consistent with earlier analyses. Higher complete response rates (CRR) were observed with epcoritamab in 2L vs overall (Table). Median duration of response (mDOR) was 25.8 mo and median duration of complete response (mDOCR) was not reached (NR). Median progression-free survival (mPFS) was 7.9 mo. Median overall survival (mOS) was 27.2 mo. Conclusions: With longer follow-up, the overall safety profile remained consistent with previous report, with no new safety signals identified. Responses observed with epcoritamab were durable and mOS was 27.2 mo. Higher CRR observed in the 2L group suggested enhanced benefit with using epcoritamab in earlier LOTs. Clinical trial information: NCT05451810 . EPCORE NHL-6 efficacy outcomes. Outcome, 95% CI 2L (n=42) Overall (n=92) ORR % 66.7, 50.5–80.4 64.1, 53.5–73.9 CRR % 57.1, 41.0–72.3 48.9, 38.3–59.6 mPFS mo 11.4, 5.5–NR 7.9, 4.2–NR mDOR mo NR, 8.7–NR 25.8, 25.8–NR mDOCR mo NR, NR–NR NR, 24.8–NR mOS mo NR, NR–NR 27.2, 13.4–NR
Lee et al. (Thu,) studied this question.