IsoBio, Inc., a U.S.-based radiotherapeutic development company, has successfully closed its initial Series Seed financing round, raising $5 million from ASP Isotopes Inc. (NASDAQ: ASPI). The funding will support the development of antibody-isotope conjugates (AICs), a novel class of targeted cancer therapeutics that combine monoclonal antibodies with radioactive isotopes to deliver potent anti-tumor activity while minimizing off-target toxicity.
Addressing Critical Supply Chain Challenges
The strategic partnership between IsoBio and ASP Isotopes directly addresses one of the most significant barriers in radiotherapeutic development: isotope supply chain reliability. According to the companies, clinical development and commercial progress of radiotherapies have been frequently constrained by limited supply of commonly used isotopes in recent years.
The collaboration with ASP Isotopes, including its nuclear medicine subsidiary PET Labs, is designed to reduce isotope supply chain uncertainty and provide IsoBio with a competitive advantage in developing novel targeted radiotherapies. This is particularly important as complex isotopes become increasingly tailored for specific tumor treatments and are not readily available for development by other companies.
Novel Radioisotope Platform
IsoBio is developing radiotherapeutics containing multiple isotopes, including Lutetium-177, Actinium-225, Terbium-161, and other undisclosed novel radioisotopes. These isotopes will be attached to antibodies using the company's proprietary linker and conjugation technology to create highly potent antibody-isotope conjugates.
The AICs platform is designed to provide a highly targeted approach for difficult-to-treat tumors, allowing for maximal efficacy while minimizing off-target toxicity. The company plans to target both derisked and validated tumor antigens as well as novel tumor targets.
Leadership and Strategic Vision
IsoBio was co-founded and is led by Bruce Turner, M.D., Ph.D., a radiation oncologist and well-known biotech executive. Dr. Turner brings extensive experience from his previous roles, including co-leading the merger of companies now known as Immunome (NASDAQ: IMNM), a targeted oncology biotech with clinical programs focusing on radiation therapeutics and antibody-drug conjugates (ADCs).
"My entire career has been spent caring for and treating cancer patients," commented Dr. Turner. "Now with the help of ASPI and PET Labs we will be able to quickly create novel radioisotopes using established antibodies that have been validated by regulatory authorities and millions of patients throughout the world. I am looking forward to working with ASPI and PET Labs to get these therapeutics into clinical trials quickly."
Dr. Turner has assembled a team of industry experts and scientific innovators, including leading radiation oncologists, medical oncologists, nuclear medicine physicians, and manufacturing experts. He is also the co-founder and CEO of Xanadu Bio, a second-generation nanoparticle company focused on nucleic acid delivery in immunology, oncology, and vaccines, and previously served as an executive with Roche Pharmaceuticals in Basel, Switzerland.
Manufacturing and Development Capabilities
The partnership leverages PET Labs' 15-year track record in drug development expertise and formulation capabilities. Dr. Gerdus Kemp, Ph.D., CEO of PET Labs, noted that ASP Isotopes' investment has enhanced their capability to help develop novel radiotherapeutics and diagnostics that should improve patient outcomes in difficult-to-treat cancers.
IsoBio will establish offices and laboratories in Seattle, Washington, and Gladwyne, Pennsylvania, positioning the company to leverage both locations' scientific ecosystems for its development programs.
Market Context and Future Outlook
The radiotherapeutics market has seen growing interest as companies seek to develop more targeted approaches to cancer treatment. The combination of monoclonal antibodies with radioactive isotopes represents a promising strategy for delivering cytotoxic radiation directly to tumor cells while sparing healthy tissue.
ASP Isotopes Inc. specializes in developing technology and processes for isotope production across multiple industries, employing proprietary Aerodynamic Separation Process (ASP technology). The company's focus on producing highly enriched isotopes for healthcare applications aligns with the growing demand for specialized isotopes in emerging therapeutic applications.
The companies plan to jointly host an investor webcast to discuss the collaboration, scheduled for 10 AM EST on Wednesday, July 30, 2025, providing additional details about their strategic partnership and development timeline.
