ARO-MAPT-SC

**ARO-MAPT-SC** is an investigational RNA interference (RNAi) therapeutic developed by Arrowhead Pharmaceuticals using its proprietary Targeted RNAi Molecule (TRiM™) platform for subcutaneous administration. It is designed to silence central nervous system (CNS) expression of the **microtubule-associated protein tau (MAPT)** gene, which encodes the tau protein—a key driver of aggregation in tauopathies such as Alzheimer's disease. By reducing tau protein levels, it aims to prevent or reverse toxic accumulation in early Alzheimer's (mild cognitive impairment due to AD and mild AD dementia), potentially slowing disease progression. The drug crosses the blood-brain barrier for uniform CNS distribution, including deep brain regions, enabling infrequent dosing (e.g., monthly or quarterly). It is currently in a Phase 1/2a trial (NCT07221344) evaluating safety, tolerability, pharmacokinetics, pharmacodynamics, and CSF biomarkers in healthy volunteers and early AD patients.[1][4][6][9]