Biotech company ABL Bio announced on Friday that it has signed a clinical trial collaboration and supply agreement with MSD, a subsidiary of US-based Merck & Co., Inc.

Under the agreement, the companies are to assess ABL103 in combination with MSD's anti-PD-1 therapy, KEYTRUDA® (pembrolizumab) in patients with advanced or metastatic solid tumours.

According to the terms of the agreement, ABL Bio is carrying out a phase 1b/2 clinical trial to assess the safety and efficacy of ABL103 in combination with KEYTRUDA. In this combination study, MSD is to provide KEYTRUDA.

ABL103, a bispecific antibody, simultaneously targets B7-H4 and 4-1BB. ABL103 and is one of the pipeline programs in which ABL Bio's 4-1BB based bispecific antibody platform 'Grabody-T' has been implemented. Grabody-T is aimed at activating T cells only in the tumour microenvironment, reducing the liver toxicity of conventional 4-1BB monoclonal antibody and improving the antitumor activity. ABL103 also has the mechanism to activate the 4-1BB signalling pathways in the tumour microenvironments where the B7-H4 antigens exist, enabling T cells to selectively attack tumour cells while sparing normal cells. The dose escalation part of the phase one clinical trial for ABL103 is currently being conducted in South Korea.