[89Zr]Zr-DFO-BIIB080 + BIIB080

[89Zr]Zr-DFO-BIIB080 + BIIB080 is an investigational combination product consisting of a **radiolabeled version of BIIB080** ([89Zr]Zr-DFO-BIIB080, where BIIB080 is conjugated to desferrioxamine and labeled with zirconium-89) administered together with **unlabeled BIIB080**. BIIB080 is an **antisense oligonucleotide** that targets the messenger RNA (mRNA) for **microtubule-associated protein tau (MAPT)**, leading to the reduction of tau protein synthesis in neurons. Tau protein tangles are implicated in the pathogenesis and progression of **Alzheimer's disease**. The radiolabeled BIIB080 ([89Zr]Zr-DFO-BIIB080) allows for **positron emission tomography (PET)** imaging to study **central nervous system biodistribution** following intrathecal injection. This combination is primarily being tested to evaluate the CNS biodistribution, safety, and tolerability of BIIB080 and its radiolabeled counterpart for biomarker and imaging studies in Alzheimer's disease[1][7].