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3018 First Results of the Acsé Pembrolizumab Phase II in the Primary CNS Lymphoma (PCNSL) Cohort

Program: Oral and Poster Abstracts
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
Monday, December 7, 2020, 7:00 AM-3:30 PM

Khe Hoang-Xuan, MD, PhD1*, Roch Houot, MD, PhD2*, Carole Soussain, MD, PhD3, Marie Blonski, MD4*, Anna Schmitt, MD5*, Vincent Delwail, MD6*, Gandhi Laurent Damaj, MD, PhD7, Herve Ghesquieres, MD, PhD8*, Frédéric Peyrade, MD9*, Adrian Tempescul, MD10*, Julie Abraham, MD11*, Philippe Agape, MD12*, Guido Ahle, MD13*, Nathalie Baize, MD14*, Pierre Bories, MD15*, Chantal Campello, MD16*, Emmanuel Gyan, MD, PhD17, Fabrice Jardin, MD, PhD18*, Philippe Rey, MD19*, Sylvain Choquet, MD20*, Caroline Houillier, MD21*, Nathalie Cassoux, MD, PhD22*, Valerie Touitou, MD, PhD23*, Nadine Martin-Duverneuil, MD24*, Frederic Legrand25*, Assia Lamrani-Ghaouti26*, Ophelie Querel26*, Natalie Hoog Labouret, MD25*, Clotilde Simon26*, Sylvie Chevret, MD, PhD27* and Christophe Massard, MD, PhD28*

1Department of Neurooncology, La Pitie Salpetriere Hospital, Assistance Publique Hopitaux de Paris, Paris, France
2Hematology Department, CHU Rennes, Rennes, France
3Hematology Department, Rene Huguenin Hospital, Institut Curie, Saint-Cloud, France
4CHU Nancy, Nancy, France
5Institut Bergonié, Bordeaux, France
6CIC 802 INSERM, CHU Poitiers, Poitiers, FRA
7CHU de Caen Normandie, Normandie, France
8Department of Hematology, Centre Hospitalier Lyon-Sud, University Claude Bernard Lyon 1, Pierre Benite, France
9Department of Medical Oncology, Centre Antoine Lacassagne, Nice, France
10Department of Hematology, University Hospital of Brest, Brest, France
11Clinical Hematology Service, CHU Limoges, Limoges, FRA
12Hematology Department, ICO Rene Gauducheau, Saint-Herblain, France
13Neurology Department, CH Colmar, Colmar, France
14CHU Angers, Angers, France
15Hematology Laboratory, Onco-occitanie Network, Toulouse University Institute of Cancer-Oncopole, Toulouse, France
16CHU Marseille, Neurooncology Unit ,Hôpital La Timone, Marseille, France
17Centre Hospitalier Universitaire, Service D'Hemaologie Et Therapie Cellulaire, Tours Cedex, France
18Department of Hematology, Centre Henri Becquerel, Rouen, France
19Hematology, Centre Leon Berard, Lyon, France
20Hematology Department, La Pitie Salpetriere Hospital, Assistance Publique Hopitaux de Paris, Paris, France
21LOC network, La Pitie Salpetriere Hospital, Assistance Publique Hopitaux de Paris, Paris, France
22Institut Curie, Paris, FRA
23Department of Ophtalmology, AP-HP, HôPital Pitié-Salpêtrière, Paris, FRA
24Department of Neuroradiology, APHP, CHU Pitié-Salpêtrière, Paris, France
25Inca, Boulogne Billancourt, France
26Unicancer, Paris, France
28Gustave Roussy Cancer Campus, Villejuif, France

Background: AcSé Pembrolizumab is a Phase 2, open-label, single-arm, multi-cohort, multicentric study investigating the efficacy and safety of pembrolizumab monotherapy in patients with advanced rare cancers (NCT03012620). Here, we report the first results of Pembrolizumab in the cohort of Primary Central Nervous System Lymphoma (PCNSL).

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.

*signifies non-member of ASH