STORM Therapeutics, a clinical-stage biotechnology company focused on targeting RNA modifications to reprogram cells and develop novel cancer therapies, announced it has raised $56 million in a Series C financing round and dosed the first patient in its Phase 2 sarcoma trial for lead candidate STC-15. The Series C financing was backed by existing investors including M Ventures, Pfizer Ventures, Taiho Ventures LLC, IP Group plc, UTokyo Innovation Platform Co., Ltd., and Fast Track Initiative.
The funding will support the continued development of STC-15, a first-in-class oral small molecule inhibitor of METTL3, including advancement of its Phase 2 monotherapy study in selected sarcoma indications. The trial is designed to potentially support an accelerated regulatory approval pathway while laying the groundwork for broader clinical development across additional oncology indications.
STC-15 targets METTL3, an RNA-modifying enzyme that regulates cancer stem cell differentiation. This process plays a critical role in the formation and progression of sarcomas and other malignancies. In a Phase 1 monotherapy study, STC-15 demonstrated durable tumor regression across multiple sarcoma subtypes, highlighting its potential to reprogram malignant progenitor cells. Additional results from this study are expected to be presented at a medical conference in 2026.
Sarcoma is a rare cancer that originates in bone or soft tissues such as muscle, fat, cartilage, and blood vessels. It accounts for approximately 1 percent of adult cancers and 15 percent of pediatric cancers. These tumors often lack the driver mutations or immunogenic traits that make them responsive to conventional therapies, increasing the need for novel treatment approaches like METTL3 inhibition.
STORM’s research builds on advancements in epitranscriptomics, particularly the role of RNA-modifying enzymes in maintaining stem cell-derived tumors. METTL3-driven mRNA methylation is believed to support tumor growth and survival in sarcomas, making it a promising therapeutic target. The ongoing Phase 2 trial will evaluate the anti-tumor effects of inhibiting this pathway.
KEY QUOTES:
“Advancing our first-in-class METTL3 inhibitor, STC-15, into Phase 2 clinical development marks a pivotal breakthrough in tackling cancers characterized by aberrant cell differentiation. This milestone highlights our scientific innovation and the potential to create new therapeutic options for patients with substantial unmet needs. We are grateful for the steadfast support from our investors and are encouraged by the robust durability and activity demonstrated with STC-15 in Phase 1 studies. As we begin our Phase 2 trial, our focus remains on addressing critical unmet needs in sarcoma for the benefit of patients.”
Jerry McMahon, Chief Executive Officer, STORM Therapeutics
“The launch of the Phase 2 trial for STC-15 represents a significant advancement in the treatment landscape for sarcoma and other tumors driven by METTL3. STC-15’s novel mechanism of action targets sarcomas at their vulnerability, reprogramming malignant cells toward cell cycle arrest and apoptosis. We are hopeful that this research will yield meaningful insights and, ultimately, new therapeutic avenues for patients with pressing unmet needs.”
Jonathan Trent, MD, University of Miami, Sylvester Comprehensive Cancer Center
