Current adoptive cell therapies primarily focus on CD8 T cells, potentially overlooking the critical role of CD4 T cells in mounting a robust and sustained immune response against solid tumors. Existing methods may also lack the ability to provide a long-term source of reprogrammed T cells for durable remission.

Tactiva Therapeutics is developing a next-generation adoptive cell therapy platform that engineers both CD4 and CD8 T cell receptors (TCRs) to enhance the immune response against solid tumors. This approach leverages a library of TCRs from both CD8 and CD4 T cells that specifically recognize and attack cancer cells, with CD4-TCRs augmenting the anti-tumor function of CD8-TCRs. In addition to genetically modifying mature T cells, Tactiva reprograms patient-derived hematopoietic stem cells (HSCs) with unique TCRs. As these reprogrammed HSCs mature in vivo, they become a continual, long-term source of cancer-fighting T cells, leading to a sustained attack on cancer cells and potentially durable remission. The platform harnesses the synergistic effects of CD8-TCRs and CD4-TCRs, along with HSC-derived T cells, to provide a more potent and lasting therapeutic effect.

Engineered CD4-TCRs exhibit cytotoxic function and enhance the anti-tumor activity of CD8-TCRs.

Utilizes patient-derived hematopoietic stem cells (HSCs) to create a long-term, self-renewing source of reprogrammed T cells.

Combined administration of CD8 and CD4 TCRs results in highly efficacious and sustained tumor control in preclinical models.

TCRs are selected from a library that specifically recognizes and attacks cancer cells.

HSC-derived T cells continuously replenish the supply of anti-tumor T cells bearing Tactiva's TCRs.

The primary target audience includes cancer patients with solid tumors who are seeking more effective and durable treatment options, as well as oncologists and hematologists specializing in cell-based immunotherapies.