Biocytogen and CtM Bio look to enhance immunotherapy by turning cold tumors hot

The partners are aiming to produce antibody drugs that can expand the potential of immunotherapy to support the treatment of cancer and other debilitating diseases, leveraging the tools each company is bringing to the table.

As part of the collaborative project, Beijing-headquartered, Biocytogen, will be responsible for screening fully human antibodies against specific targets by leveraging its proprietary TCR-mimic antibody development platform, while CtM Bio will use its T cell engager platform to co-develop T cell engagers targeting intracellular tumor-associated antigens.

Biocytogen said its TCR-mimic antibody development platform, which utilizes a strain of fully human RenMab mice expressing a human leukocyte antigen (HLA) gene, is designed to facilitate the discovery of antibodies against intracellular tumor-associated antigens. The company maintains that fully human antibody sequences obtained from the platform can support the development of T cell engagers, bispecific/multispecific antibodies, and CAR-T therapies.

CtM Bio, based in Shanghai, claims extensive experience in the discovery of innovative drug candidates for the treatment of life-threatening diseases. It said its T cell engager platform with differentiated properties is expected to turn ‘cold tumors’ into ‘hot tumors’, making them more susceptible to immunotherapy.

Hot and cold tumors

According to a paper in Theranostics​​,​ immune checkpoint inhibitors (ICIs) have greatly improved the clinical efficacy of malignant tumor therapy, but ICI-mediated antitumor responses depend on the infiltration of T cells capable of recognizing and killing tumor cells.

“ICIs are not effective in ‘cold tumors’ which are characterized by the lack of T-cell infiltration. To realize the full potential of immunotherapy and solve this obstacle, it is essential to understand the drivers of T-cell infiltration into tumors.”​

Some of mechanisms underlying ‘cold tumors’ include impaired T-cell priming and deficient T-cell homing to tumor beds. ‘Hot tumors’ with significant T-cell infiltration are associated with better ICI efficacy, said the authors of that review.

Wider project

Biocytogen is also involved in a large-scale project to develop antibody drugs for more than 1000 potential druggable targets, known as Project Integrum; through that, it is engaging with dozens of partners globally with the idea of producing a variety of first-in-class antibody drugs.