The article presents preclinical data demonstrating domatinostat´s efficacy and mode of action in Merkel Cell Carcinoma (MCC). The data shows that domatinostat not only exerts direct anti-tumoral effects, but also restores HLA class I surface expression on MCC cells – and as a result, restores surviving MCC cells‘ susceptibility to recognition and elimination by cytotoxic T cells.

Frank Hermann, MD, Chief Development Officer at 4SC commented: "The preclinical results published in this article strongly support our clinical development strategy to combine domatinostat with avelumab in patients with advanced MCC – to effectively address critical escape mechanisms in this deadly cancer and synergize with immune checkpoint blockade. We acknowledge the scientific value and relevance of the work of Professor Becker and his research team, and look forward to seeing clinical data from our MERKLIN 2 and MERKLIN 1 studies."

About domatinostat
Domatinostat is an orally administered small molecule class I selective HDAC inhibitor. It strengthens the body’s own anti-tumor immune response, influences the tumor and tumor microenvironment, making the tumor more visible to the immune system and facilitating the infiltration of immune cells into the tumor.
Domatinostat has been investigated in a Phase I study in 24 heavily pretreated patients with several types of advanced hematologic cancers and was well tolerated. Positive signs of anti-tumor efficacy were also observed; with one complete remission (28 months) and one partial responder (8 months).
In addition to its therapeutic potential in cancer monotherapy, 4SC is evaluating domatinostat’s capacity as a partner in combination therapies, specifically in the immuno-oncology area. In this respect, 4SC initiated a Phase Ib/II study of domatinostat in combination with the anti-PD-1 checkpoint inhibitor pembrolizumab in patients with advanced-stage melanoma from which initial data was presented at ESMO 2019. A second Phase II study of domatinostat in combination with the anti-PD-L1 checkpoint inhibitor avelumab in patients with advanced-stage microsatellite-stable gastrointestinal cancer is currently being conducted by Prof. David Cunningham at The Royal Marsden NHS Foundation Trust in London, UK. And in collaboration with the Netherlands Cancer Institute in Amsterdam, the DONIMI Study, a multicenter, investigator-sponsored phase 1b study, testing the combination of domatinostat, nivolumab, and ipilimumab, in high risk stage III melanoma in the neoadjuvant setting.

Forward-looking information
Information set forth in this press release contains forward-looking statements, which involve risks and uncertainties. The forward-looking statements contained herein represent the judgement of 4SC as of the date of this press release. Such forward-looking statements are neither promises nor guarantees, but are subject to a variety of risks and uncertainties, many of which are beyond 4SC’s control, and which could cause actual results to differ materially from those contemplated in these forward-looking statements. 4SC expressly disclaims any obligation or undertaking to release any updates or revisions to any such statements to reflect any change in its expectations or any change in events, conditions or circumstances on which any such statement is based.