Efficacy, safety, tolerability, and PK of the HDAC inhibitor resminostat in sorafenib-refractory hepatocellular carcinoma (HCC): Phase II SHELTER study.

4115 Background: Resminostat (R), an oral HDAC inhibitor, was studied in the SHELTER trial evaluating safety, PK and efficacy in HCC patients (pts) refractory to sorafenib (S). R was explored as monotherapy and within a novel resensitization approach to overcome tolerance to S by the combination of both drugs. Methods: Pts with advanced HCC (BCLC B/C) were included in a multi-center, two-arm trial. Radiologic progression under S firstline therapy had to be confirmed by central review (RECIST) prior to study entry. A dose escalation of R (range 200 to 600 mg) combined with S (400 or 800 mg) was performed. Arm A investigated the drug combination (R+S), Arm B the monotherapy of R (600 mg). Primary objective was the progression-free survival rate (PFSR) after 12 weeks (w). Secondary objectives included safety, tolerability, tumor response, PFS, TTP, OS and the analyses of PK and biomarkers (BM), incl. AFP, VEGF, HDAC enzyme inhibition, histone acetylation and gene expressions in peripheral blood. Results: 50 ...