resminostat and Pancreatic-Neoplasms

Resminostat is an oral hydroxamate inhibitor of class I, IIb, and IV histone deacetylases. S-1 is widely used to treat biliary tract cancer and pancreatic cancer in Japan. We performed a phase I study of resminostat combined with S-1 as second-line or later therapy in Japanese patients with biliary tract or pancreatic cancer. A total of 27 patients were enrolled. We determined the optimal regimen for resminostat/S-1 therapy in part 1, and investigated its safety and efficacy in part 2. In part 1, 17 patients were enrolled. One DLT (anorexia and stomatitis, respectively) occurred with each of regimens 2 and 3. In part 2, an additional 10 patients received regimen 3, which was selected in part 1. Regimen 3 was resminostat (200 mg/day on Days 1 to 5 and Days 8 to 12: 5 days on/2 days off) plus S-1 (80-120 mg/day according to body surface area on Days 1 to 14) repeated every 21 days. A total of 16 patients (13 with biliary tract cancer and 3 with pancreatic cancer) received regimen 3 and it was well tolerated. The most frequent treatment-related adverse events were thrombocytopenia and anorexia (11 patients each, 69%). The disease control rate was 81.3% (84.6% for biliary tract cancer and 66.7% for pancreatic cancer, respectively). Median progression-free survival was 3.1 months (5.5 and 2.3 months), while median overall survival was 8.8 months (10.2 and 4.7 months). In conclusion, regimen 3 was well tolerated by patients with pre-treated biliary tract or pancreatic cancer.

Topics: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Biliary Tract Neoplasms; Drug Combinations; Female; Follow-Up Studies; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Male; Maximum Tolerated Dose; Middle Aged; Oxonic Acid; Pancreatic Neoplasms; Prognosis; Sulfonamides; Tegafur; Tissue Distribution

Oncolytic viruses (OV) constitute highly promising innovative biological anticancer agents. However, like every other antitumoral compound, OV are also faced with both primary and secondary mechanisms of resistance. To overcome those barriers and moreover amplify the therapeutic potential of OV, we evaluated a novel combined approach composed of the oral histone deacetylase inhibitor resminostat and an oncolytic measles vaccine virus (MeV) for a future epi‑virotherapy of pancreatic ductal adenocarcinoma. Cytotoxicity assays revealed that combined epi-virotherapeutic treatment of four well-characterized human pancreatic cancer cell lines resulted in a beneficial tumor cell killing as compared to either monotherapeutic approach. Notably, epi-virotherapeutic treatment of MIA PaCa-2 and partly also of PANC‑1 pancreatic cancer cells resulted in a tumor cell mass reduction being significantly more pronounced than it would be expected in case of an additive effect only, indicating a synergistic mode of action when combining resminostat with MeV. We further found that the epigenetic compound resminostat neither impaired MeV growth kinetics nor prevented the activation of the interferon signaling pathway which plays an important role in mediating primary and secondary resistances to OV. Moreover, we yielded information that the pharma-codynamic function of resminostat was presumably not altered in the course of pancreatic cancer cell infections with MeV. Taken together, these promising results favor the onset of epi-viro-thera-peutic clinical trials in patients suffering from advanced pancreatic ductal adenocarcinoma.

Topics: Apoptosis; Blotting, Western; Cell Proliferation; Combined Modality Therapy; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Measles Vaccine; Oncolytic Virotherapy; Oncolytic Viruses; Pancreatic Neoplasms; Real-Time Polymerase Chain Reaction; RNA, Messenger; Sulfonamides; Tumor Cells, Cultured; Virus Replication