Merus has dosed the first patient in a Phase I clinical trial of MCLA-158 to treat patients with solid tumours with an initial focus on metastatic colorectal cancer.
The first-in-human trial follows approval of an investigational new drug (IND) application by the US Food and Drug Administration (FDA) for MCLA-158 last month.
This approval has lead the way for Merus to conduct the trial in the US.
Initially, the open-label, multi-centre trial will be carried out across various sites in Europe.
The trial includes two parts, a dose escalation and a dose expansion phase.
The dose escalation part aims to determine the appropriate dose of MCLA-158, while the dose expansion aspect will examine safety and tolerability of the defined dose of MCLA-158 for solid tumours patients.
Both parts will also evaluate the preliminary anti-tumour activity of single-agent MCLA-158.
Merus CEO Ton Logtenberg said: "The commencement of our Phase I clinical trial of MCLA-158 is an important milestone for the advancement of our pipeline of bispecific antibodies obtained from our Biclonics technology platform.
"We believe MCLA-158 has the potential to address features that limit currently approved colorectal cancer-targeted therapies, including issues with off-target toxicity and inability to target tumour stem cells, and thus, potentially treat a broader population of patients more effectively."
MCLA-158 has been developed to bind to cancer stem cells demonstrating leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5) and epidermal growth factor receptors (EGFR).
Functional review of patient-derived colorectal tumours previously showed that MCLA-158 was more effective at inhibiting tumour growth and promoting apoptosis than cetuximab, an approved targeted therapy comparator for metastatic colorectal cancer.