Iadademstat in combination with azacitidine in patients with newly diagnosed acute myeloid leukaemia (ALICE): an open-label, phase 2a dose-finding study

Iadademstat is a potent, selective, oral inhibitor of both the enzymatic and scaffolding activities of the transcriptional repressor lysine-specific demethylase 1 (LSD1; also known as KDM1A) that showed promising early activity and safety in a phase 1 trial and strong preclinical synergy with azacitidine in acute myeloid leukaemia cell lines. Therefore, we aimed to investigate the combination of iadademstat and azacitidine for the treatment of adult patients with newly diagnosed acute myeloid leukaemia. The open-label, phase 2a, dose-finding ALICE study was conducted at six hospitals in Spain and enrolled patients aged 18 years or older with newly diagnosed acute myeloid leukaemia not eligible for intensive chemotherapy and an ECOG performance status of 0–2. In the dose escalation portion of the trial, patients received a starting dose of iadademstat at 90 μg/m2 per day (with de-escalation to 60 μg/m2 per day and escalation up to 140 μg/m2 per day) orally, for 5 days on, 2 days off weekly, with azacitidine 75 mg/m2 subcutaneously, for seven of 28 days. The primary objectives were safety (analysed in the safety analysis set; all patients who received at least one dose of study treatment) and establishing the recommended phase 2 dose; secondary objectives included response rates in the efficacy analysis set (all patients who had at least one efficacy assessment). This study is registered on EudraCT (EudraCT 2018-000482-36) and has been completed. Between Nov 12, 2018, and Sept 30, 2021, 36 patients with newly diagnosed acute myeloid leukaemia were enrolled; the median age was 76 (IQR 74–79) years, all patients were White, 18 (50%) were male, and 18 (50%) were female, and all had intermediate-risk or adverse-risk acute myeloid leukaemia. The median follow-up was 22 (IQR 16–31) months. The most frequent (≥10%) adverse events considered to be related to treatment were decreases in platelet (25 [69%]) and neutrophil (22 [61%]) counts (all grade 3–4) and anaemia (15 [42%]; of which ten [28%] were grade 3–4). Three patients had treatment-related serious adverse events (one fatal grade 5 intracranial haemorrhage, one grade 3 differentiation syndrome, and one grade 3 febrile neutropenia). Based on safety, pharmacokinetic and pharmacodynamic data, and efficacy, the recommended phase 2 dose of iadademstat was 90 μg/m2 per day with azacitidine. 22 (82%; 95% CI 62–94) of 27 patients in the efficacy analysis set had an objective response. 14 (52%) of 27 patients had comp