November 25, 2025 — Leads & Copy —
Zetagen Therapeutics, Inc., a clinical-stage biopharmaceutical company, has successfully completed its Series B1 financing round, raising $12,908,000. The funding round was oversubscribed, indicating strong investor confidence in Zetagen’s Zeta Platform and its potential to transform breast cancer treatment.
The proceeds from this financing will be used to support the commercialization of Zetagen’s lead drug candidate, ZetaMet™ (Zeta-BC-003), and to advance the clinical development of ZetaMast™ (Zeta-MBC-005). Funds will also be used to complete preclinical studies and GMP manufacturing of ZetaPrime™ (Zeta-PBC-007).
Joe C. Loy, CEO of Zetagen Therapeutics, said the oversubscribed Series B1 round underscores the promise of Phase 2a clinical data for ZetaMet in treating metastatic breast cancer to bone. Loy noted the company’s discovery of a novel molecular pathway, triggered by their compounds activating a conserved nuclear receptor, that enables predictability in dosing and outcomes.
Zetagen’s Zeta Platform focuses on developing first-of-its-kind therapies for metastatic and primary breast cancer, utilizing proprietary carriers that deliver tumoricidal compounds via a single injection. This approach aims to minimize severe off-target side effects and increase survival rates.
The Zeta Platform includes:
ZetaMet™ (Zeta-BC-003), targets metastatic breast cancer in bone, aiming to cease lytic activity, inhibit pain, and regenerate new bone via intratumoral injection, without systemic limitation, minimizing skeletal related events, such as fractures. A Phase 2a clinical trial at the University of British Columbia demonstrated a Complete Response in treated lesions, full bone regeneration, and no skeletal-related events. Preliminary results will be presented at the upcoming San Antonio Breast Cancer Symposium (SABCS) conference.
ZetaMast™ (Zeta-MBC-005), a novel hydrogel that delivers two synergistic tumoricidal agents via a single intratumoral injection for breast cancer liver metastases (BCLM). Preclinical results published in PLOS ONE showed reduced tumor burden, prevention of soft tissue metastases, and improved survival. A Phase 1b dose-escalation study is planned for the first half of 2026.
ZetaPrime™ (Zeta-PBC-007), a neo-adjuvant treatment engineered for intratumoral administration after diagnosis. The hydrogel-like lipid carrier formulation is designed for controlled release of two small molecules—one being a novel molecular entity—and has the ability to deliver a CDK4 or CDK4/6 protein inhibitor. The approach targets primary breast cancer, aiming to mitigate off-target effects, reduce the necessity for lumpectomies and mastectomies, decrease radiation exposure, and enhance patient survival. A single-dose in-vivo study showed improved survival and tumor suppression over Tamoxifen and Verzenio in a mouse mammary fat pad model; these results will be presented at the upcoming San Antonio Breast Cancer Symposium (SABCS) conference.
This Series B1 funding follows other strategic milestones for Zetagen, including:
- Expansion of the company’s global IP portfolio to more than 70 issued patents, including Composition-of-Matter patents & claims on ZetaMet™, ZetaMast™, and ZetaPrime™.
- Successful completion of the Phase 2a study of ZetaMet™ for metastatic breast cancer to bone.
- Accepted abstracts by San Antonio Breast Cancer Symposium (SABCS) on ZetaMet™ preliminary clinical results and ZetaPrime™ in-vivo results of head-to-head comparison towards Verzenio.
Zetagen will attend & present at the 2025 San Antonio Breast Cancer Symposium (SABCS) and attend the 2026 JP Morgan Healthcare Conference.
Joe C. Loy, CEO of Zetagen Therapeutics.
Source: Zetagen Therapeutics, Inc.
