Investigation of the HDAC inhibitor resminostat in patients with sorafenib-resistant hepatocellular carcinoma (HCC): Clinical data from the phase I/II SHELTER study.

262 Background: Resminostat (4SC-201), an oral pan-HDAC inhibitor, is in clinical development in a variety of cancer indications. The SHELTER study aims to evaluate safety, tolerability and efficacy in HCC patients (pts) exhibiting progressive disease under sorafenib first-line therapy. Methods: Pts with advanced HCC, (BCLC B or C) are included in a multi-center, open-label, two-arm parallel group trial. Radiologic progression under sorafenib is determined acc. to RECIST by central review prior to study entry. For Arm A, dose escalation of resminostat and sorafenib is performed to determine the MTD. Resminostat is administered orally once-daily in a “5+9” schedule, consisting of 5 consecutive treatment days followed by a 9-day rest period resulting in 14 day cycles on dose levels of 200 (DL1), 400 (DL2) and 600 mg (DL3+4), either combined with continuously taken sorafenib at 400 (DL1-3) or 800 mg (DL4) (Arm A), or as resminostat monotherapy (600 mg, Arm B). Primary objective is to determine progression-fr...