Fuzionaire DX

Fuzionaire Diagnostics ("Fuzionaire Dx"), which presents itself as Fuzionaire Theranostics ("Fuzionaire Tx"), is a radiopharmaceutical company applying silicon-fluorine chemistry to build matched diagnostic and therapeutic radiopharmaceutical pairs for oncology. Its patented HetSiFA compositions incorporate radioisotopes into disease-targeting ligands rapidly and at ambient temperature, using existing radiochemistry infrastructure. The company originally launched the platform as a disease-agnostic radiolabeling method intended to broaden the range of biological targets accessible to positron emission tomography (PET), to lower radiotracer cost and preparation time given fluorine-18's roughly 110-minute half-life, and to serve as an in vivo pharmacology tool in drug discovery.

The platform now supports chemically matched diagnostic and therapeutic companions derived from common molecular architectures. HetSiFA-based diagnostics can be labeled with fluorine-18 or gallium-68, while HetSiFA-based therapeutics are developed for lutetium-177 radioligand therapy, with selective evaluation of terbium-161 and lead-212 depending on target biology. The company also describes work on endocyclic SiFA architectures. Fuzionaire positions fluorine-18 as a scalability strategy enabling centralized manufacturing, regional distribution and standardized quantitative imaging, and frames its matched pairs as supporting patient selection, biodistribution assessment and prospective dosimetry.

The team spans chemistry, radiochemistry, biophysics, medicine and operations. Nick Slavin is co-founder and CEO; Christopher Waldmann, PhD, a radiopharmacist who invented the HetSiFA technology as a postdoc at UCLA's Crump Institute for Molecular Imaging in collaboration with the Grubbs laboratory at Caltech, is Chief Scientific Officer; Thomas Singleton, PhD, is Vice President, Chemistry; Bethany Cates is Director of Operations and corporate secretary; Li Boynton serves on the board of directors; Nova Spivack is a co-founder. Anton Toutov, PhD, was co-founder and chief science officer during the company's earlier Fuzionaire Diagnostics period.

Founding story

The company's technology traces to silicon and alkali-metal catalysis chemistry from the Caltech laboratory of Nobel laureate Robert Grubbs. Earlier company materials describe the platform as based on a discovery by Anton Toutov during his PhD under Grubbs, which created a branch of catalysis using Earth-abundant alkali metals such as potassium and sodium and made chemical processes possible at ambient temperature and pressure without precious metals. The company's current materials state that Christopher Waldmann invented the HetSiFA technology as a postdoctoral researcher at UCLA's Crump Institute for Molecular Imaging in collaboration with the Grubbs lab, and that this invention constitutes the scientific basis of Fuzionaire Theranostics. Fuzionaire Dx was co-founded by CEO Nick Slavin, CSO Anton Toutov and Nova Spivack, and Fuzionaire Theranostics is described as applying Fuzionaire's silicon chemistry, with Fuzionaire itself characterized as an R&D lab spun out of the Grubbs lab at Caltech.

Business model

Development of proprietary radiopharmaceutical candidates built on an in-house, patented chemistry platform, advanced through academic, clinical and industrial research collaborations and positioned for strategic partnering; the platform is also described as a potential tool for pharmaceutical drug discovery.

Traction

The lead program FTX-426 targets GRPR-expressing solid tumors, including prostate and breast cancer, and is designed as a matched fluorine-18/lutetium-177 theranostic pair, with additional undisclosed oncology programs. The CEO states that as of 2025 the company's collaborations span four continents and that its targeted therapies and PET imaging agents are being tested in cancer patients in Germany on a compassionate use basis. A multiyear research collaboration was established with the VCU College of Engineering in 2019, and early materials cited use of the radiolabeling platform by several clinical research centers and foundations.

Latest developments

The company now operates under the Fuzionaire Theranostics identity, presenting HetSiFA as a platform for matched PET and radioligand therapy programs across fluorine-18, gallium-68, lutetium-177, terbium-161 and lead-212, with FTX-426 in GRPR-expressing solid tumors as the lead program and exploration of endocyclic SiFA architectures. Per the CEO, targeted therapies and PET imaging agents were being tested in cancer patients in Germany on a compassionate use basis as of 2025.