Novel agents in relapsed/refractory diffuse large B-cell lymphoma

Targeting CD19-positive lymphomas with the antibodydrug conjugate loncastuximab tesirine: preclinical evidence of activity as a single agent and in combination therapy

Antibody-drug conjugates (ADC) represent one of the most successful therapeutic approaches introduced into clinical practice in the last few years. Loncastuximab tesirine (ADCT-402) is a CD19-targeting ADC in which the antibody is conjugated through a protease cleavable dipeptide linker to a pyrrolobenzodiazepine dimer warhead (SG3199). Based on the results of a phase II study, loncastuximab tesirine was recently approved for adult patients with relapsed/refractory large B-cell lymphoma. We assessed the activity of loncastuximab tesirine using in vitro and in vivo models of lymphomas, correlated its activity with levels of CD19 expression, and identified combination partners providing synergy with the ADC. Loncastuximab tesirine was tested across 60 lymphoma cell lines. It had strong cytotoxic activity in B-cell lymphoma cell lines. The in vitro activity was correlated with the level of CD19 expression and intrinsic sensitivity of cell lines to the ADC's warhead. Loncastuximab tesirine was more potent than other anti-CD19 ADC (coltuximab ravtansine, huB4-DGN462), although the pattern of activity across cell lines was correlated. The activity of loncastuximab tesirine was also largely correlated with cell line sensitivity to R-CHOP. Combinatorial in vitro and in vivo experiments identified the benefit of adding loncastuximab tesirine to other agents, especially BCL2 and PI3K inhibitors. Our data support the further development of loncastuximab tesirine for use as a single agent and in combination for patients affected by mature B-cell neoplasms. The results also highlight the importance of CD19 expression and the existence of lymphoma populations characterized by resistance to multiple therapies.

Progress in deciphering the role of p53 in diffuse large B-cell lymphoma: mechanisms and therapeutic targets

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma subtype, accounting for 30%-40% of non-Hodgkin lymphoma in adults. The mechanisms underlying DLBCL occurrence are extremely complex, and involve the B-cell receptor (BCR) and Toll-like receptor (TLR) signaling pathways, as well as genetic abnormalities and other factors. With the development of high-throughput sequencing, an increasing number of abnormal genes have been identified in DLBCL. Among them, the tumor protein p53 (TP53/p53) gene is important in DLBCL occurrence. Patients with DLBCL carrying TP53 gene abnormalities generally have poor prognosis and studies of p53 have potential to provide a better basis for their treatment. Normally, p53 is maintained at low levels through its interaction with murine double minute 2 (MDM2), and prevents tumorigenesis by mediating cell cycle arrest, apoptosis, and repair of damaged cells, among other processes. Therefore, the prognosis of patients with DLBCL harboring TP53 gene abnormalities (mutations, deletions, etc.) is poor, and targeting p53 for tumor therapy has become a research hotspot, following developments in molecular biology technologies. Current treatments targeting p53 mainly act by restoring the function or promoting degradation of mutant p53, and enhancing wild-type p53 protein stability and activity. Based on the current status of p53 research, exploration of existing therapeutic methods to improve the prognosis of patients with DLBCL with TP53 abnormalities is warranted.

Prediction of 5-year overall survival of diffuse large B-cell lymphoma on the pola-R-CHP regimen based on 2-year event-free survival and progression-free survival

This study aimed to predict the 5-year overall survival (OS) benefit of pola-R-CHP versus R-CHOP in the POLARIX trial based on the 2-year event-free survival (EFS) and progression-free survival (PFS) rates in diffuse large B-cell lymphoma (DLBCL). We identified randomized controlled trials (RCT) published before 31 May 2023. The correlation between the logarithmic (log) hazard ratio (HR) for EFS (HREFS) or PFS (HRPFS) and the HR for OS (HROS) was estimated at the trial-level. Correlation analysis was performed between 2-year PFS or EFS and 5-year OS rates at the treatment arm-level. Linear regression models were used to calculate the 5-year OS of pola-R-CHP and R-CHOP. In the included 20 RCTs, a linear correlation between HREFS (r = 0.765) or HRPFS (r = 0.534) and HROS was observed at the trial- level. Two-year EFS (r = 0.918) or 2-year PFS (r = 0.865) correlated linearly with 5-year OS. Linear regression analysis between 2-year EFS/PFS and 5-year OS gave estimated 5-year OS rates between pola-R-CHP and R-CHOP of 6.4% and 6.3%, respectively. Two-year EFS and PFS are feasible early endpoints in patients with DLBCL treated primarily with immunochemotherapy. The pola-R-CHP regimen is expected to improve 5-year OS.

Novel IRAK4 Inhibitors for Treating Asthma, COPD, Cancer, Autoinflammatory Diseases, and Autoimmune Diseases

Provided herein are novel IRAK4 inhibitors, pharmaceutical compositions, use of such compounds in treating asthma, COPD, cancer, autoinflammatory diseases, and autoimmune diseases, and processes for preparing such compounds.