Inhibrx Biosciences (INBX) late Tuesday released preliminary safety and efficacy data from phase 1 testing of its ozekibart drug candidate, with four patients with advanced or metastatic unresectable colorectal adenocarcinoma showing either a complete or partial response and six patients showing stable.

Inhibrx said durable disease control was seen for at least 180 days in 46.2% of the patients treated with a combination of ozekibart and the Folfiri chemotherapy regimen, with a median 7.85 months of progression-free survival. The patient with a complete response had undergone three prior lines of treatment, the company said, while two of the partial responses occurred in patients who had failed prior Folfiri-based chemotherapy.

Adverse events were observed in 84.6% of the patients, although most were grade 1 or 2 in severity Inhibrx said.

Based on the early results, Inhibrx has started an expansion cohort to validate the recent data in up to 50 patients, it said. The data is expected in Q3.