Racura Oncology Limited (ASX:RAC), a late clinical-stage biopharmaceutical company, announced on Monday that the Safety Review Committee (SRC) for the Phase 1 HARNESS-1 trial has approved its lead oncology drug, RC220, to proceed to the next planned dose level of 100 mg/m2.

HARNESS-1 (RAC-020) is a Phase 1a/b clinical trial evaluating RC220 in combination with osimertinib in patients with epidermal growth factor receptor-mutant (EGFR-mutant) non-small cell lung cancer (NSCLC).

The approval was received after a review of all safety data from both Cohort 1 patients, who were administered RC220 at 50 mg/m2 by intravenous infusion in combination with osimertinib at 80 mg daily. The second Cohort 1 patient has now received three doses of RC220, dosed 21 days apart, without any dose-limiting toxicities or treatment-related safety concerns.

Following review of available safety and pharmacokinetic data, the study is expected to advance into a double-blind, randomised Phase 1b expansion stage in which 40 patients will receive one of two RC220 dose levels in combination with osimertinib.