Racura Oncology Doses First Patient in Phase 1 HARNESS-1 Trial of RC220 for EGFR-Mutant NSCLC
Key Insights
Racura Oncology (search) has dosed the first patient in its Phase 1 HARNESS-1 trial evaluating RC220 combined with osimertinib in EGFR-mutant non-small cell lung cancer (search).
The patient received a 50 mg/m² intravenous infusion of RC220 at Monash Health in Victoria, with no adverse events observed during or after dosing.
The trial employs a staged dose-escalation design using single-patient cohorts before expanding to identify the maximum tolerated dose of the RC220-osimertinib combination.
Racura Oncology (search) (ASX: RAC) has dosed the first patient in its Phase 1 HARNESS-1 multi-centre clinical trial, marking the initiation of clinical evaluation for RC220 in epidermal growth factor receptor (EGFR (search))-mutant non-small cell lung cancer (NSCLC). The patient received an intravenous infusion of RC220 at 50 milligrams per square metre, administered by Principal Investigator Associate Professor Surein Arulananda and his team at Monash Health in Victoria, with no adverse events observed during or after the infusion.
The HARNESS-1 trial is designed to assess whether RC220, a proprietary formulation of (E,E)-bisantrene (search), can be safely combined with the standard-of-care tyrosine kinase inhibitor (TKI) osimertinib — marketed as Tagrisso by AstraZeneca — in patients with EGFR (search)-mutant NSCLC for whom resistance to certain TKI treatments remains a significant clinical challenge.
Trial Design and Dose-Escalation Strategy
HARNESS-1 is a Phase 1a/b study that incorporates an observational screening stage using circulating tumour DNA (ctDNA), a blood-based marker of cancer activity and growth, to help identify and enrol eligible patients. Between 12 and 40 participants are expected in the dose-escalation stage.
The trial employs a staged approach, utilising single-patient cohorts for the first three dose escalations at 50 mg/m², 100 mg/m², and 150 mg/m², before progressing to larger cohorts to identify the maximum tolerated dose (MTD) of RC220 in combination with osimertinib. This design is intended to support careful dose escalation while generating early safety and pharmacokinetic (PK) data, including progression-free survival, overall survival, and changes in cancer-specific mutations.
Following dose escalation, the study will move into a double-blind, randomised Phase 1b expansion stage enrolling 40 patients. Participants will continue treatment with RC220 and osimertinib until one year of treatment is completed or until disease progression, unacceptable toxicity, or withdrawal of consent occurs.
RC220 and the Bisantrene Platform
RC220 is a proprietary formulation of (E,E)-bisantrene (search), a small molecule anti-cancer agent designed to silence cancer growth pathways through G4-DNA and RNA binding, including the cancer growth regulator MYC (search). (E,E)-bisantrene has previously demonstrated therapeutic activity in cancer patients and possesses a well-characterised safety profile.
Beyond the HARNESS-1 trial, RC220's clinical development programs include a Phase 3 trial in acute myeloid leukaemia (search) and a Phase 1a/b trial in combination with doxorubicin chemotherapy for patients with solid tumours.
Addressing an Unmet Need
Dr Daniel Tillett, Chief Executive Officer and Managing Director of Racura Oncology (search), underscored the significance of the milestone. "Treating the first patient in HARNESS-1 is an important step in the clinical development of RC220 and reflects the progress being made across Racura's oncology pipeline," he said.
"This trial is focused on a patient group where resistance to current targeted therapies remains a significant challenge. We are grateful to A/Prof Surein Arulananda and his team at Monash Health for their work in recruiting and treating the study's first participant, and we thank the patients and families supporting this clinical research."