Biotechnology company MEKanistic Therapeutics announced on Tuesday that the US Food and Drug Administration (FDA) has cleared the Investigational New Drug application for MTX-531, its lead oncology candidate.

Subject to standard start-up activities, MEKanistic may now proceed with its planned Phase 1 clinical study of MTX-531.

MTX-531 is a potential first-in-class small molecule designed to selectively inhibit PI3K and EGFR, two signalling pathways implicated in tumour growth, survival, and adaptive resistance.

The Phase 1 study will evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary anti-tumour activity of MTX-531 in patients with advanced solid tumours with dysregulated EGFR and/or PI3K signalling, including head and neck and endometrial cancers. The study is planned to include dose-escalation with expansion cohorts at multiple US sites, with dosing of the first patient anticipated in the third quarter of 2026.