TwoStep Therapeutics Raises $62.5M Series A and Wins FDA IND Clearance for First-in-Class Multi-Specific Peptide-Drug Conjugate TS-104
核心洞察
TwoStep Therapeutics (搜索) closed an oversubscribed $62.5 million Series A, bringing total capital raised to $71.2 million to fund oncology development.
The FDA cleared the IND for TS-104 (搜索), a first-in-class multi-specific peptide-drug conjugate, allowing a first-in-human Phase 1 trial to begin.
TS-104 (搜索) pairs a polyspecific integrin-binding peptide with the cytotoxic payload MMAE (搜索) to target five tumor-associated integrins (搜索) simultaneously.
TwoStep Therapeutics (搜索), a San Carlos, California-based biotechnology company developing multi-specific targeted therapies for solid tumors (搜索), announced an oversubscribed $62.5 million Series A financing alongside U.S. Food and Drug Administration (搜索) clearance of its Investigational New Drug application for TS-104 (搜索), the company's lead multi-specific peptide-drug conjugate. The IND clearance enables TwoStep to initiate a first-in-human Phase 1 clinical trial of TS-104, with patient enrollment expected to begin later this year.
The Series A brings TwoStep's total capital raised to $71.2 million. The round was led by Insight Partners (搜索) and Medical Excellence Capital (搜索), with M Ventures (搜索) — the strategic corporate venture capital arm of Merck KGaA, Darmstadt, Germany — and Pfizer Ventures (搜索) joining as co-lead investors, alongside existing investors NFX (搜索) and 2048 Ventures (搜索). Stanford University, where the foundational science behind TwoStep was developed before the company launched in 2024, participated as an additional investor.
"This financing, together with FDA clearance of the IND, marks an important inflection point for TwoStep and positions us to advance TS-104 (搜索), our lead peptide-drug conjugate, through Phase 1 clinical development in oncology," said Caitlyn Miller, PhD, Co-Founder and Chief Executive Officer of TwoStep Therapeutics (搜索). "This trial will provide the first clinical evaluation of the multi-specific targeting approach at the heart of TwoStep and begin to assess its potential to broaden the reach of targeted therapies. Beyond TS-104, the proceeds will enable us to advance our radioligand program and expand into next-gen peptide conjugates."
A Polyspecific Peptide Platform Aimed at Tumor Heterogeneity
TwoStep's platform centers on a polyspecific integrin-binding peptide (PIP), a small synthetic molecule designed to engage five tumor-associated integrins (搜索) simultaneously. TS-104 (搜索) pairs PIP with MMAE (搜索), a cytotoxic payload with established clinical precedent in antibody-drug conjugates.
The design addresses a central limitation of current tumor-targeted therapies. Most such therapies depend on high and relatively uniform expression of a single cell-surface target. In solid tumors (搜索), however, target expression can vary substantially across tumor types, between patients, and even among cells within the same tumor. This heterogeneity can restrict the addressable patient population, complicate patient selection, and allow target-low or target-negative tumor cells to escape treatment.
Because most solid tumors (搜索) express integrins (搜索) heterogeneously, and single-antigen targeting approaches can miss target-low or target-negative cell populations, TwoStep's multi-target design is intended to broaden tumor recognition across diverse patient populations.
Pipeline Beyond TS-104
Beyond its lead program, TwoStep is developing a radioligand therapy program using the same PIP scaffold with a different therapeutic payload. The company said the Series A proceeds will fund the Phase 1 trial of TS-104 (搜索), advance the radioligand therapy program, and support expansion into next-generation peptide conjugates.
TwoStep was founded in 2024 by Caitlyn Miller, who serves as chief executive officer, in collaboration with three faculty from Stanford University: Jennifer Cochran, Nobel laureate Carolyn Bertozzi, and Ronald Levy.