Abstract T107

Treatment patterns and survival outcomes of patients relapsing after frontline Nivolumab-AVD in advanced stage classical Hodgkin lymphoma (cHL)

Background: Nivolumab (nivo) with AVD (NAVD) is standard-of-care for frontline (1L) treatment (tx) of advanced stage (AS) cHL in the U.S. There is a gap in data on patients (pts) relapsing after 1L NAVD and the utility of re-challenge with checkpoint inhibitors (CPI). Thus, we sought to evaluate tx patterns and outcomes of pts with cHL relapsing after 1L NAVD.

Methods: Pts included had cHL treated with 1L NAVD between 2018 and 2025 at 23 US sites. Primary refractory disease was defined as less than a complete response (CR) at end of treatment (EOT) PET-CT. Second line (2L) tx was considered CPI-based if it included CPI with chemotherapy (chemo) or Brentuximab Vedotin (BV) and non-CPI based if BV +/- chemo. PFS was calculated from date of auto-SCT (ASCT).

Results: Overall, 50 pts were included, 52% were male, 24 (48%) were primary refractory to 1L tx and 15 (30%) had relapse <12 months (mo) from EOT. 47 (94%) had biopsy proven relapse. The median age at relapse was 55 (17-84). At relapse, 78% had AS disease, 15% had B symptoms, and 42% had extranodal involvement. 49 pts (98%) received 2L tx; 23 pts (47%) received CPI-based tx and 26 pts (53%) received non-CPI based tx (Fig 1). Non-CPI tx included BV-bendamustine (benda) (n=13, 50%), BV-ICE (n=9, 35%), BV monotherapy (n=3), and ICE (n=1). CPI-based tx included CPI with chemo (n=16, 70%), BV+nivo (n=6, 26%) and nivo monotherapy (n=1). Among all response-evaluable pts (n=43/49), the ORR/CR rates were 86% and 65%, respectively. ORR (95% vs 78%) and CR rates (70% vs 61%) were numerically higher for CPI-based vs non-CPI based 2L tx. 71% (17/24) of primary refractory pts received non-CPI 2L tx. Among evaluable primary refractory pts (n=21/24), ORR was 76% and CRR was 57% (CPI-based vs non-CPI CRR was 50 vs 60%, respectively). 10 pts (20%) required third line tx. Of these, 8 pts had PD after 2L tx. The other 2 pts had inadequate response to 2L. With a median follow up (f/up) of 8.1 mo (0.1-60), there were 12 total events with 9 progressions and 3 deaths (1 cHL, 2 unknown during salvage). 31 patients (62%) proceeded to ASCT. Median f/up post ASCT was 5.3 mo (0.3-57.3). 6-month PFS/OS post ASCT was 100%, with 1 late relapse/death from cHL post-ASCT at 60 months. Two pts were ineligible for ASCT.

Conclusions: Both CPI-based and non-CPI-based therapies remain effective at achieving disease control and bridging to ASCT post NAVD relapse. Outcomes after ASCT appear similar to prior literature with longer f/up needed.