Evaluation of the safety of C-1311 (SYMADEX) administered in a phase 1 dose escalation trial as a weekly infusion for 3 consecutive weeks in patients with advanced solid tumours

PurposeC-1311 is a member of the novel imidazoacridinone family of anticancer agents. This phase 1 trial was designed to investigate the safety, tolerability and preliminary anti-tumour activity of C-1311.Patients and methodsThis was a phase 1, inter-subject dose escalating and pharmacokinetic study of intravenous (IV) C-1311, administered weekly during 3 consecutive weeks followed by 1 week rest (constituting 1 cycle) in subjects with advanced solid tumours.ResultsTwenty-two (22) patients were treated with C-1311, the highest dose given was 640 mg/m2. All subjects experienced one or more treatment-related adverse events (AEs). The most frequently observed treatment-related AEs were neutropaenia and nausea (50% each), followed by vomiting (27%), anaemia (23%), asthenia (23%) and diarrhoea (18%). Most treatment-related AEs were of Common Terminology Criteria for Adverse Events (CTCAE) grades 1–2, except for the blood and lymphatic system disorders, which were primarily of grades 3–4. The recommended dose (RD) of C-1311 administered as once weekly IV infusions for 3 weeks every 4 weeks is 480 mg/m2, with the dose limiting toxicity (DLT) being grade 4 neutropaenia lasting more than 7 days. Treatment at this dose offers a predictable safety profile and excellent tolerability.ConclusionThe safety profile and preliminary anti-tumour efficacy of C-1311, observed in this broad-phase dose-finding study, warrants further evaluation of the compound.