Turning Patient Cells into Cancer Fighters

Cancer therapy could soon include a personalized cancer treatment based on engineered immune cells derived from a patient’s individual cells. The approach involves attaching proteins to these cells, receptors that target antigens present in cancer cells to then enable a patient’s immune system to seek out and destroy tumors.

The immune cells are initially collected from the patient and stored in a liquid nitrogen freezer for Tactiva Therapeutics, a Buffalo-based immuno-oncology startup. The company then engineers both immune cells and adult stem cells that can be infused back into the patient.

“Adoptive cell therapy is not new, but we’re hoping to make it better,” says Matthew Colpoys, CEO of Tactiva Therapeutics. “Our primary immune cell construct has the potential to be more potent and persistent than other approaches. More importantly, we engineer a second type of cell—a hematopoietic stem cell—that can mature into additional cancer-fighting immune cells. We’re recruiting a second killer to the fight, and because it’s a stem cell, it creates a sustained attack, serving as a continual, long-term source of new killer immune cells.”

A partnership with the Buffalo Institute for Genomics and Data Analytics (BIG) at the University at Buffalo (UB) supports Tactiva’s future growth, enabling the company to search for additional tumor-targeting receptors—called T-cell receptors, specifically—that can be added to cells to transform them into cancer fighters.

Tactiva Therapeutics’ treatment platform, called dual enhanced adoptive cell therapy (DEACT), involves engineering two kinds of cells. The first are mature T-cells (immune cells) called CD8s, that are reprogrammed to seek out and kill cancer. The second are blood stem cells, which home into patients’ bone marrow and mature into another kind of T-cell called CD4s. The unique CD4s are also programmed to target and destroy tumors.

“CD4 cells ordinarily are purely helper cells that help CD8s stay active longer. Preliminary animal data show that our CD4s also recognize and kill tumor cells,” Colpoys says. “Because these specialized CD4 T-cells are derived from stem cells, they remain in circulation, thus having the potential to protect against recurrence or relapse of tumor cells that possess the target.”

Tactiva Therapeutics is advancing the DEACT platform for treatment of multiple myeloma and several forms of cancer that express the target, including ovarian, melanoma and non-small cell lung cancer.

Currently, the company’s engineered T-cells are able to target tumors in many, but not all, patients. But with assistance from BIG, Tactiva is embarking on research to discover new tumor-targeting receptors that can be added to T-cells, with the goal of making the company’s platform available to a greater population.

BIG funded the purchase of equipment such as a cell sorter, incubators, centrifuges and storage freezers to aid in this meticulous process, which involves identifying, cloning and testing the effectiveness of different T-cell receptors against various tumor targets.

“We are excited to support Tactiva in this next generation immunotherapy,” says Christina Orsi, associate vice president for economic development at UB. “Advancing the development of personalized medicine as a key driver of the Buffalo life sciences ecosystem is an important focus of the BIG initiative.”