Strand Therapeutics Raises $153M Series B to Advance mRNA Tumor Drugs

Strand Therapeutics raised $153 million in a Series B round backed by Big Pharma investors including Regeneron, Amgen, and returning investor Eli Lilly1234.

The funding will accelerate the development of Strand's pipeline, especially STX-001, a programmable mRNA therapy that expresses interleukin-12 (IL-12) directly in the tumor microenvironment1234.

Initial Phase 1 clinical data for STX-001, presented at the 2025 ASCO Annual Meeting, showed promising results:
at least one confirmed complete response, multiple partial responses, prolonged disease stabilization, and a favorable safety profile even in previously treatment-resistant patients1234.

STX-001 is being tested for advanced solid tumors, with a particular focus on melanoma and triple-negative breast cancer; it is administered directly into tumors to prompt a systemic anti-cancer immune response234.

The Series B round brings Strand’s total funding to over $250 million to date234.

Strand is also advancing additional pipeline programs, such as STX-003 for non-small cell lung cancer and other tumors, and two programs for blood malignancies4.

This financing comes amid increased political scrutiny of mRNA technology in the US, though Strand focuses on therapeutic, not vaccine, applications of mRNA14.

Sources:

1. https://www.fiercebiotech.com/biotech/strands-big-pharma-backed-series-b-brings-153m-advance-mrna-tumor-drugs

2. https://www.biospace.com/press-releases/strand-therapeutics-raises-153-million-series-b-financing-to-further-advance-programmable-mrna-therapeutic-pipeline

3. https://www.biospace.com/business/big-pharma-backed-mrna-startup-bags-153m-series-b-amid-policy-headwinds

4. https://www.biopharmadive.com/news/strand-series-b-mrna-cancer-jake-becraft/757101/