Zabinostat is a novel epigenetic regulator with immune-regulatory properties. It is an orally available small molecule with anti-tumour properties and a well-tolerated safety profile in humans. The agent causes tumour cells to be recognised by the immune system and has shown efficacy in colorectal cancer and lymphomas.
Zabinostat works both as a monotherapy and in combination with PD-1 inhibitors. In a Phase I clinical trial to determine safety and dosage, it was found that zabinostat showed efficacy signals in multiple lymphoma subtypes. Phase II studies are ongoing to investigate zabinostat’s efficacy in relapsed or refractory peripheral T-cell lymphoma (PTCL), with interim data reporting significant, durable tumour shrinkage.
A Phase II study (CAROSELL) has been conducted to investigate the effects of zabinostat and nivolumab in late-stage MSS colorectal cancer. Results showed around half of the study subjects benefited from the combination therapy, with survival extension of more than 3 years in some. A Phase IIIa study (CAROSELL-2) will be conducted to investigate biomarkers enabling patients to be selected based on their predicted sensitivity to treatment, followed by a Phase IIIb registrational study in MSS CRC.
Emactuzumab is a best-in-class therapeutic antibody against CSF-1R, designed to target and deplete tumour-associated macrophages (TAMs). It has shown a favourable safety profile in patients and promising efficacy for diffuse tenosynovial giant cell tumours (“TGCT”), also known as pigmented villonodular synovitis (”PVNS”), a rare disease characterised by the proliferation of macrophages in the synovial tissue in the joint and tendon sheath.
A clinical study in diffuse TGCT patients showed that emactuzumab treatment resulted in an overall response rate of 71% (45/63) and a disease control rate of 98% (62/63). At one- and two-year follow-up, MRI scans showed that 19/27 patients (70%) and 9/14 patients (64%), respectively, were still in response at these time points, demonstrating emactuzumab’s long duration of response (Cassier et al, 2020).