VelosBio, a San Diego-based biopharma company, said that it has dosed the first patient in a phase 2 clinical trial of its investigational antibody-drug conjugate (ADC) VLS-101 in patients having solid tumors.

VLS-101, which is the company’s lead product candidate, targets a cell-surface protein called ROR1.

Expressed during embryofetal development, ROR1 is however not seen before birth. It is generally not expressed on normal cells in either children or adults but can reappear on malignant tissues, including on solid tumors.

By targeting the ROR1 protein, VLS-101 is designed to selectively deliver cancer-fighting therapeutics to tumor cells, while not affecting normal cells.

The mid-stage clinical trial of VLS-101 will aim to enroll patients who were previously treated with solid tumors. These include breast cancer, lung cancer, and other cancer that are thought to express ROR1.

The participating patients will be administered with VLS -101 2.5 mg/kg intravenously once every three weeks as long as they are safely benefiting from the drug candidate.

The primary endpoint of the phase 2 trial is the objective response rate as determined by standard response criteria. The clinical trial will evaluate safety, pharmacokinetics, pharmacodynamics, and immunogenicity of the investigational antibody-drug conjugate and study the influence of biomarkers on the result.

Dave Johnson – CEO of VelosBio said: “VLS-101 dosing of the first patient in our Phase 2 solid tumor trial represents a key milestone for our lead ROR1-directed clinical program.

“Based on the broad expression of ROR1 across different cancer types, and our pre-clinical data showing VLS-101 antitumor activity in solid tumors, we are excited to advance this investigational candidate as a potential new therapy for difficult-to-treat cancers.”

  Dave Johnson, Solid tumors, USA, VelosBio, VLS-101