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San Francisco, CA

Advancing a gene therapy platform targeting deadly brain cancers through scalable immuno-oncology innovation.

• Scientific innovation: Developing a universal immuno-gene therapy platform for cancer
• Experienced leadership: Team includes leading scientists and biotech executives from top institutions
• Backed by investors: Supported by Founders Fund, Lux Capital, and other notable venture firms
• Preclinical results: Animal studies show curative potential for aggressive brain cancers
• Strong IP portfolio: Multiple patent families cover key advancements in delivery, safety, and scalability

Siren Biotechnology is raising funds to support the development of its universal adeno-associated virus (AAV) immuno-gene therapy platform, with the goal of transforming how cancer is treated. The company is focused on creating an off-the-shelf therapy that merges the precision of gene therapy with the strength of immunotherapy, targeting some of the deadliest cancers, starting with aggressive brain tumors like high-grade gliomas. This new approach uses AAV to deliver engineered cytokines that train the body to fight cancer cells more effectively, offering an alternative to traditional treatments like chemotherapy and radiation. Backed by preclinical studies showing curative potential and a strong intellectual property portfolio, Siren’s platform is designed to work across multiple cancer types, reducing development time and expanding therapeutic reach.

The funds will be used to advance the company’s scientific progress toward clinical trials, scale manufacturing capabilities, and pursue regulatory milestones. Led by a team of experts in gene therapy and oncology from institutions like Stanford, UCSF, and Mount Sinai, and supported by prominent venture capital firms, Siren is aiming to accelerate development through expedited FDA pathways. The company also plans to explore partnerships and licensing opportunities to expand its reach while maintaining control of its core technology. With a growing market demand for effective brain cancer treatments and an innovative approach that is designed to improve both safety and scalability, Siren is positioning itself to address a critical need in cancer care.

Company Info

Siren Biotechnology is developing a universal AAV immuno-gene therapy platform to treat aggressive cancers, starting with brain tumors.

Siren Biotechnology is a San Francisco-based company developing a universal adeno-associated virus (AAV) immuno-gene therapy platform aimed at treating some of the deadliest forms of cancer. Their approach merges gene therapy with immunotherapy by using AAV vectors to deliver engineered cytokines—natural proteins that help the body recognize and eliminate cancer cells. This platform is designed to work across multiple solid tumor types without requiring customization for each cancer, potentially accelerating development timelines and expanding treatment accessibility.

Siren’s lead focus is on brain cancers, including high-grade gliomas, due to their high mortality rates and unmet therapeutic need. The company’s platform has demonstrated curative potential in preclinical studies and is protected by a growing intellectual property portfolio covering AAV delivery innovations, regulatory enhancements, and scalable manufacturing processes. The leadership team includes experts in gene therapy, oncology, and clinical development from institutions such as Stanford, UCSF, and Roche. With a market projected to grow to over $5 billion by 2030, Siren Biotechnology aims to establish a new standard of care in brain cancer treatment through its scalable and off-the-shelf therapy approach.