Abstract P124

Outcomes in patients with relapsed/refractory Hodgkin lymphoma after failure following frontline brentuximab vedotin-based treatment

Background: Brentuximab vedotin (BV) combined with AVD chemotherapy is a standard of care for treatment (tx) of advanced stage classic Hodgkin lymphoma (cHL) based on improved progression-free survival (PFS) and overall survival (OS) compared to ABVD. Available data regarding outcomes of patients (pts) with relapsed or refractory (RR) cHL is primarily derived from pts who received ABVD, with limited data from pts progressing after BV-based frontline regimens. We performed a multicenter retrospective analysis to assess outcomes in pts with RR cHL after BV-based initial tx.

Methods: Consecutive patients with RR cHL after BV-containing frontline tx were identified at each institution. Descriptive statistics were used to describe the patient population. Response to tx was assessed by the treating MD based on response criteria at time of assessment.

Results: 105 pts treated between Dec 2015 and Nov 2023 were included. Most pts received BV-AVD (76%) as their initial tx, 16% received ABVD/BV-AVD, 8% received BV in other combinations. The median age at first relapse was 35 years (y, range 18-82), and 52% were male. 56% had primary refractory disease, 28% relapsed within 12 months of completing initial tx, and 15% had late relapse. At relapse, 57% pts presented with stage III/IV disease, 17% had B symptoms, and 18% had bulk ≥ 5 cm.

The most frequently used salvage regimens were anti-PD1+chemotherapy combinations (55%), followed by chemotherapy alone (29%), BV+nivolumab (8%), anti-PD1 monotherapy (7%), and RT only (1%). In all pts, the overall response rate (ORR) to first salvage tx was 88%, the complete response (CR) rate was 66%. First salvage tx that included PD-1 blockade (n=73) led to an ORR of 96% with 72% CR versus ORR 84% and 61% CR for chemotherapy-only salvage (n=31). Eighty seven pts (83%) underwent autologous stem cell transplantation (ASCT). Among these pts, 29% of pts received >1 line of salvage tx and 6% required ≥ 3 lines. Overall, 79% of pts received PD-1 blockade as part of salvage tx. 13% received peri-ASCT RT, and 8 (10%) received post-ASCT maintenance tx. At a median follow-up of 20 months, the 2y PFS from the start of 1st salvage was 63% and the 2y OS was 96%.

Conclusions: In this cohort of pts with RR cHL after BV-containing frontline tx, a majority of pts achieved CR and proceeded to ASCT. Despite most receiving novel salvage regimens, PFS may be lower than expected compared to available data regarding outcomes after novel salvage tx.