Responses and Outcomes after Second-Line Therapy in Transplant-Eligible Patients with DLBCL Relapse over 1 Year after First-Line Therapy

• Published in: Blood 2023-11, Vol.142 (Supplement 1), p.4970-4970
• Main Authors: Qualls, David A, Shah, Gunjan L., Shouval, Roni, Caron, Philip, David, Kevin A., Falchi, Lorenzo, Ghione, Paola, Hamlin, Paul A., Horwitz, Steven M., Intlekofer, Andrew M., Johnson, William, Kumar, Anita, Lahoud, Oscar Boutros, Lue, Jennifer Kimberly, Moskowitz, Alison, Noy, Ariela, Palomba, Maria Lia, Torka, Pallawi, Vardhana, Santosha A, Zelenetz, Andrew D., Okwali, Michelle, Dahi, Parastoo Bahrami, Scordo, Michael, Lin, Richard J., Perales, Miguel-Angel, Salles, Gilles
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2023-182733

Introduction Chimeric antigen receptor T-cell therapy (CAR T) is approved as second-line therapy in patients with large B cell lymphoma (LBCL) that is refractory to, or relapsed within 1 year of, initial therapy. In patients with LBCL that relapses more than 1 year after completion of initial therapy, salvage chemoimmunotherapy followed by high-dose chemotherapy and autologous stem cell transplant (ASCT) remains the standard of care for transplant-eligible patients. However, data on the outcomes of salvage chemoimmunotherapy with intent for ASCT for this specific population are lacking. Methods We retrospectively reviewed patients with relapsed LBCL more than 1 year after 1 st line therapy who received salvage treatment. We included patients seen at our institution prior to the start of salvage therapy, who began therapy between 1/2008 and 1/2023, and were treated with stated intent to proceed to ASCT. We excluded patients with CNS involvement at relapse and those not evaluable for response. The primary outcome was progression-free survival (PFS), defined as the time from initiation of salvage therapy to LBCL progression or death. Event-free survival (EFS) was defined as time from salvage initiation to change in lymphoma therapy, disease progression, or death. Additional key outcomes included overall survival (OS), overall response rate (ORR) and complete response rate (CRR) to salvage therapy, and outcomes after subsequent CAR T. Outcomes for important subgroups using baseline characteristics were compared. ORR and CRR were compared using Fisher's exact test. PFS, EFS and OS were estimated using the Kaplan-Meier method, and differences were tested by the log-rank test. Results A total of 78 patients met inclusion criteria, with characteristics summarized in Table 1. Median time from completion of initial therapy to relapse was 31.2 months (range, 12.3 - 177 months). CRR to salvage therapy was 76%, with a 94% ORR. In 60 patients who completed ASCT, CRR was 85%. With a median of 45 months' follow-up from salvage initiation, median PFS was 50 months (95% confidence interval (CI) of 25 - NR), and median EFS was 29.2 months (95% CI, 19.6 - NR)( Figure 1). Median OS was 132 months (95% CI 108 - NR). On subgroup analysis, factors significantly associated with shorter PFS were time from last treatment to relapse < 36 months, Ann Arbor stage 3-4, LDH above normal, and increased international prognostic index at relapse. Other factors such as age, gender, salvage r