The success of early CAR-T cell therapies was partly luck. Future therapies face a high bar, as an ideal target must meet three criteria: 1) be abundant on cancer cells, 2) be indispensable for the cancer's survival, and 3) be dispensable for the patient's healthy tissues to avoid lethal toxicity.

Previous IL-2 therapies from companies like Nektar and Synthorix broadly targeted beta and gamma receptors, which proved clinically ineffective. Synthakyne represents a strategic shift, designing molecules to selectively target the trimeric alpha-beta-gamma receptor found on potent, antigen-activated T cells, avoiding widespread, toxic stimulation.

T-cell receptor (TCR) therapies offer a significant advantage over monoclonal antibodies by targeting intracellular proteins. They recognize peptides presented on the cell surface, effectively unlocking 90% of the proteome and requiring far fewer target molecules (5-10 copies vs. 1000+) to kill a cancer cell.

An innovative strategy for solid tumors involves using bispecific T-cell engagers to target the tumor stroma—the protective fibrotic tissue surrounding the tumor. This novel approach aims to first eliminate this physical barrier, making the cancer cells themselves more vulnerable to subsequent immune attack.

Create's strategy is not limited to a single cell type. They view success in solid tumors as requiring the programming of all immune cells. Their platform can specifically engineer myeloid cells, T-cells, and NK cells in vivo, orchestrating a coordinated, multi-pronged attack on cancer.

Instead of focusing solely on T-cells, Create's platform first targets myeloid cells, which constitute up to 60% of some solid tumors. Programming these cells transforms the tumor microenvironment, enabling a 5-10x influx of CD8 T-cells. This overcomes a key barrier for T-cell therapies in solid tumors.

The primary hurdle for the entire biologics field is enhancing the therapeutic index (efficacy vs. toxicity). Because most conditions like cancer and autoimmune disorders are 'diseases of self,' therapeutics often have on-target, off-tumor effects. This fundamental problem drives the need for innovations like masking and conditional activation.

To combat immunosuppressive "cold" tumors, new trispecific antibodies are emerging. Unlike standard T-cell engagers that only provide the primary CD3 activation signal, these drugs also deliver the crucial co-stimulatory signal (e.g., via CD28), ensuring full T-cell activation in microenvironments where this second signal is naturally absent.

While immunotherapy was a massive leap forward, Dr. Saav Solanki states the next innovation frontier is combining it with newer modalities. Antibody-drug conjugates (ADCs) and T-cell engagers are being used to recruit the immune system into the tumor microenvironment, helping patients who don't respond to current immunotherapies.