Racura Oncology (ASX:RAC) said the first patient was recruited to its phase 1 HARNESS-1 clinical trial of its cancer drug candidate RC220 in patients with non-small cell lung cancer with activated epidermal growth factor receptor (EGFR) mutations being treated with osimertinib, according to a Tuesday Australian bourse filing.

The company said the trial aims to address the significant unmet medical need of preventing or delaying resistance to standard-of-care EGFR-mutant tyrosine kinase inhibitors such as osimertinib, with four additional clinical trial sites expected to be activated in the coming months.

RC220 is an experimental oral drug candidate designed to inhibit the proto-oncogene tyrosine-protein kinase (SRC) protein, which is believed to drive resistance to EGFR-targeted therapies.

The trial aims to test whether combining RC220 with osimertinib can prevent or delay tumors from developing resistance to the standard-of-care treatment, the filing added.

The company's shares rose 2% in recent Tuesday trade.