Session: 626. Aggressive Lymphoma (Diffuse Large B-Cell and Other Aggressive B-Cell Non-Hodgkin Lymphomas)—Results from Prospective Clinical Trials: Poster III
Hematology Disease Topics & Pathways:
Biological, antibodies, Diseases, Lymphoma (any), Therapies, Non-Hodgkin Lymphoma, CNS Lymphoma, checkpoint inhibitors, DLBCL, B-Cell Lymphoma, Lymphoid Malignancies
Methods: Main inclusion criteria were: relapsed or refractory PCNSL after one or several lines of treatment including high dose Methotrexate based chemotherapy, pathologically confirmed diffuse large B cell lymphoma, age>18, HIV negative, concurrent steroid medication at a dose no greater than prednisone 20 mg/day or equivalent. Patients received pembrolizumab 200 mg IV as a 30-minute infusion on Day 1 of every 21-day cycles for a maximum of 2 years. The primary endpoint was the confirmed objective response rate according to IPCG at 84 day after the start of treatment. Secondary endpoints included best response (ORR), duration of response, progression-free survival (PFS), overall survival (OS), and safety. Analysis used all enrolled patients.
Results: 50 patients suffering from PCNSL, including 9 primary vitreoretinal lymphoma (PVRL) were included from July, 2017 to October, 2019. Median age was 72 years (range: 43 to 83), Median PS (ECOG) was 1 (range 0-1). The median number of cycles was 4 (range 1-35). At 84 days from start of treatment, 6 patients responded (4 CR+2PR). Overall, 3 patients whose response was not assessed were considered as failures, and the rates of ORR (CR+PR), stable disease (SD), progressive disease (PD) were 26% (13/50, 8 CR + 5 PR), 10% (5/50), 58% (29/50), respectively. ORR was 29% (12/41) and 11% (1/9) in primary cerebral lymphoma and PVRL respectively. After a median follow-up of 6.7 months (range 0.2-27.4), median PFS was 2.6 months, with 6-month PFS of 29.8% and 6-month OS of 60.4%. In responders, median duration of response was estimated at 10 months (95%CI, 2.7 to 12.5). Grade III and IV toxicities related to the drug were observed in 4 patients (8%) and one patient (2%) respectively. No related toxic death was reported.
Conclusion: Pembrolizumab shows moderate activity in relapsed/ refractory PCNSL with acceptable toxicity, supporting further studies evaluating its use in combination therapies.
Disclosures: Hoang-Xuan: BTG: Consultancy, Research Funding. Houot: Bristol-Myers Squibb: Honoraria; MSD: Honoraria; Gilead: Honoraria; Kite: Honoraria; Roche: Honoraria; Novartis: Honoraria; Janssen: Honoraria; Celgene: Honoraria. Schmitt: Celgene: Membership on an entity's Board of Directors or advisory committees; Roche, Janssen: Honoraria. Ahle: Roche: Honoraria; Novartis: Honoraria; Biogene: Honoraria; Abbvie: Honoraria; Sanofi: Honoraria. Bories: Abbvie: Consultancy; Celgen: Consultancy; Gilead: Consultancy; BMS: Honoraria; Novartis: Honoraria. Houillier: BTG: Consultancy.