Von Hoff, Daniel D

Abstract Purpose: TRK-950 is a first-in-class humanized antibody targeting cytoplasmic activation/proliferation-associated protein-1, which is strongly expressed on the cell membrane surface in or on most solid tumors but not in or on normal tissues. This first-in-human study investigated the safety profile, pharmacokinetics (PK), and preliminary antitumor activity. Patients and Methods: Patients with treatment-refractory, locally advanced, or metastatic solid tumors were enrolled in a dose escalation/expansion study. TRK-950 was administered intravenously weekly for 3 weeks in a 28-day cycle, with doses ranging from 3 to 30 mg/kg. Dose expansion included 10 mg/kg weekly and 30 mg/kg biweekly for colorectal cancer and 10 mg/kg weekly for cholangiocarcinoma. The primary objective of this study was to determine its safety, tolerability, and maximum tolerated dose. The secondary objectives were PK, preliminary antitumor activity, and identification of potential biomarkers. Results: Thirty-six patients received at least one dose of TRK-950. In the dose escalation cohort, the maximum tolerated dose was not reached, and no dose-limiting toxicities were observed up to 30 mg/kg. Common adverse events included abdominal pain, fatigue, constipation, back pain, nausea, and decreased appetite. TRK-950 exhibited a PK profile similar to that of other IgG subclass 1 therapeutic antibodies, with linear PK parameters over the 3 to 30 mg/kg dose range. The best response was stable disease. Notably, one patient with cholangiocarcinoma showed signs of cavitation after approximately 8 months, suggesting potential antitumor activity. Conclusions: TRK-950 is safe and well tolerated, has a favorable PK profile, and should be further investigated as a monotherapy and in combination with standard treatment for various types of solid tumors. Significance: TRK-950, a humanized antibody targeting CAPRIN-1, demonstrated good tolerability, no dose-limiting toxicities, a favorable PK profile, and potential antitumor activity in this first-in-human study. Currently, TRK-950 is undergoing Phase Ib and II trials for various cancers, showing promising development potential.

Abstract Adenosquamous cancer of the pancreas (ASCP) is a subtype of pancreatic cancer that has a worse prognosis and greater metastatic potential than the more common pancreatic ductal adenocarcinoma (PDAC) subtype. To distinguish the genomic landscape of ASCP and identify actionable targets for this lethal cancer, we applied DNA content flow cytometry to a series of 15 tumor samples including five patient-derived xenografts (PDX). We interrogated purified sorted tumor fractions from these samples with whole-genome copy-number variant (CNV), whole-exome sequencing, and Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq) analyses. These identified a variety of somatic genomic lesions targeting chromatin regulators in ASCP genomes that were superimposed on well-characterized genomic lesions including mutations in TP53 (87%) and KRAS (73%), amplification of MYC (47%), and homozygous deletion of CDKN2A (40%) that are common in PDACs. Furthermore, a comparison of ATAC-seq profiles of three ASCP and three PDAC genomes using flow-sorted PDX models identified genes with accessible chromatin unique to the ASCP genomes, including the lysine methyltransferase SMYD2 and the pancreatic cancer stem cell regulator RORC in all three ASCPs, and a FGFR1-ERLIN2 fusion associated with focal CNVs in both genes in a single ASCP. Finally, we demonstrate significant activity of a pan FGFR inhibitor against organoids derived from the FGFR1-ERLIN2 fusion–positive ASCP PDX model. Our results suggest that the genomic and epigenomic landscape of ASCP provide new strategies for targeting this aggressive subtype of pancreatic cancer. Significance: These data provide a unique description of the ASCP genomic and epigenomic landscape and identify candidate therapeutic targets for this dismal cancer.