Sequence analyses of relapsed or refractory diffuse large B-cell lymphomas unravel three genetic subgroups of patients and the GNA13 mutant as poor prognostic biomarker, results of LNH-EP1 study

Advances in molecular profiling of newly diagnosed diffuse large B-cell lymphoma (DLBCL) have recently refine genetic subgroups. Genetic subgroups remain undetermined at the time of relapse or refractory (RR) disease. This study aims to decipher genetic subgroups and search for prognostic molecular biomarkers in patients with RR-DLBCL. From 2015 to 2021, targeted next-generation sequencing analyses of germline-matched tumor samples and fresh tissue from RR-DLBCL patients were performed. Unsupervised clustering of somatic mutations was performed and correlations with patient outcome were sought. A number of 120 patients with RR-DLBCL were included in LNH-EP1 study and a molecular tumor landscape was successfully analyzed in 87% of patients (104/120 tumor samples). The median age was 67.5 years (range 27.4-87.4), median number of previous treatments was 2 (range 1-9). The most frequently mutated genes were TP53 (n = 53 mutations; 42% of samples), CREBBP (n = 39; 32%), BCL2 (n = 86; 31%), KMT2D (n = 39; 28%) and PIM1 (n = 54; 22%). Unsupervised clustering separated three genetic subgroups entitled BST (enriched in BCL2, SOCS1, and TNFRSF14 mutations); TKS (enriched in TP53, KMT2D, and STAT6 mutations); and PCM (enriched in PIM1, CD79B, and MYD88 mutations). Median overall survival (OS) was 11.0 (95% confidence interval [CI]: 8.1-12.6) months. OS was not significantly different between the three genetic subgroups. GNA13 mutant was significantly associated with an increased risk of death (hazard ratio: 6.6 [95% CI: 2.1-20.6]; p = .0011) and shorter OS (p = .0340). At the time of relapse or refractory disease, three genetic subgroups of DLBCL patients were delineated, which could help advance precision molecular medicine programs.

Abstract CT141: Safety and efficacy results from a phase I dose-escalation trial of Nintedanib in combination with Pembrolizumab in patients with advanced solid tumors (PEMBIB trial)

Background: Antiangiogenic drugs can synergize with immunotherapy in preclinical models. However some molecules have shown unacceptable levels of toxicity when combined with anti-PD-1. We aimed to determine the safety and activity of the nintedanib+pembrolizumab combination. Nintedanib is an oral angiokinase inhibitor aiming the vascular endothelial growth factor receptors 1,2,3, platelet-derived growth factor receptors α,β, fibroblast growth factor receptors 1,2,3 as well as RET. Pembrolizumab is a highly selective, humanized monoclonal IgG4-kappa isotype antibody against PD-1 designed to block the negative immune regulatory signaling of the PD-1 receptor expressed by T cells.

Methods: PEMBIB is a monocentric phase Ib trial which evaluated escalating doses of continuous oral intake of nintedanib (Dose level 1 (DL1) = 150 mg BID; DL2 =200 mg BID) in combination with intravenous flat dose of pembrolizumab at 200 mg every 21 days in patients with advanced solid tumors using the rolling 6 design. A lead-in monotherapy of nintedanib was performed 7 days prior starting the C1D1 of pembrolizumab with the aim of modifying the tumor microenvironment. The primary objective was to establish the MTD of nintedanib in combination with pembrolizumab based on the assessment of DLT occurrence during the first 4 weeks (28 days since C1D1) and to determine the recommended phase II dose (RP2D). Secondary objectives included antitumor activity assessed by both RECIST v1.1 and irRECIST. The clinical activity of the combination is being further evaluated in the expansion part of this trial.

Results: As of November 24, 2016, 13 patients (12 evaluable for DLT) have been enrolled in the escalation part with the following pathology: 2 squamous cervical carcinoma, 1 MSI colorectal cancer, 1 triple negative breast cancer, 2 thymic carcinoma, 1 malignant pleural mesothelioma, 1 peritoneal mesothelioma, 1 gastric adenocarcinoma, 1 clear cell renal carcinoma, 1 neuroendocrine tumor, 1 nasopharyngeal cancer. 50% patients were male, ECOG 0 (83%) or 1. There were no grade 4-5 toxicities. The most frequent adverse events reported for more than 2 patients were alanine & aspartate aminotransferase increase, fatigue, decreased appetite, diarrhea, nausea, vomiting, hypothyroidism. Three dose-limiting toxicities of liver enzymes elevation were observed in 200 mg BID nintedanib thus recommending 150 mg BID nintedanib for the phase II part. One nasopharyngeal carcinoma, 1 squamous cervical carcinoma and 1 thymic carcinoma developed an objective RECIST partial response (ORR=25%).

Conclusions: Toxicity was consistent with the drugs profile and no unexpected events have been seen with the combination. Nintedanib at 150 mg BID with 200 mg flat dose of Pembrolizumab was well tolerated. Additional data for safety and efficacy is further evaluated in the expansion part.

Citation Format: Andreea Varga, Capucine Baldini, Patricia Martin-Romano, Antoine Hollebecque, Anas Gazzah, Rastislav Bahleda, Jessica Menis, Stephane Champiat, Yolla El-Dakdouki, Xavier Paoletti, Vincent Ribrag, Jean-Marie Michot, Saloomeh Rafie, David Planchard, Benjamin Besse, Christophe Massard, Jean-Charles Soria, Aurelien Marabelle. Safety and efficacy results from a phase I dose-escalation trial of Nintedanib in combination with Pembrolizumab in patients with advanced solid tumors (PEMBIB trial) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr CT141.