Boston, MA — Strand Therapeutics has released preclinical data showing promising proof-of-concept for STX-003, a programmable mRNA therapy designed to selectively deliver interleukin-12 (IL-12) to solid tumor tissue. The data will be presented at the upcoming 2025 annual meetings of the American Association for Cancer Research (AACR) and the American Society of Gene and Cell Therapy (ASGCT).
The company’s approach marks a significant step forward in immunotherapy by demonstrating, for the first time, that mRNA-based genetic circuitry can be programmed to express powerful cytokines like IL-12 exclusively within cancerous tissue while minimizing harmful off-target effects.
“Our proprietary mRNA platform and genetic circuitry have the potential to make systemic delivery of mRNA and expression of powerful cytokines such as IL-12 safer and more effective for patients with a range of solid tumors,” said Jacob Becraft, Ph.D., CEO and co-founder of Strand Therapeutics.
STX-003 uses self-replicating, systemically delivered mRNA to encode IL-12, a potent cytokine known for its ability to stimulate the immune system’s response against tumors. Historically, systemic administration of IL-12 has been limited due to severe toxicity caused by its activity in healthy tissues. Strand’s solution leverages advanced mRNA engineering to restrict IL-12 expression to the tumor microenvironment, dramatically improving tolerability.
Through its genetic circuits, the mRNA therapy can “sense” molecular signatures unique to tumor cells, enabling precise expression of IL-12 only in malignant tissue. The preclinical findings suggest that this technology could open the door to a new class of safer, more effective immunotherapies for difficult-to-treat solid tumors, including those located deep within the body.
“These results are unprecedented,” Becraft said. “By precisely regulating IL-12 expression through genetic programming, we’re beginning to realize the potential of mRNA as a targeted, programmable therapeutic platform.”
The early development of STX-003 was supported by funding from Wellcome Leap, a nonprofit aimed at accelerating breakthroughs in global health. Strand plans to showcase key preclinical findings, including insights into the therapy’s efficacy and tolerability, at AACR in Chicago from April 25–30 and ASGCT in New Orleans from May 13–17.
