motavizumab-YTE

Motavizumab-YTE is an investigational Fc-engineered, humanized IgG1 monoclonal antibody directed against the fusion (F) protein of respiratory syncytial virus (RSV), derived from the high-affinity anti-RSV antibody motavizumab by introducing three amino acid substitutions (M252Y/S254T/T256E, the “YTE” mutation) in the Fc region to increase binding affinity to the neonatal Fc receptor (FcRn) and thereby markedly prolong serum half-life.[1][3][12] In a first-in-human, randomized, single-dose intravenous study in healthy adults, motavizumab-YTE showed 2- to 4-fold reduced clearance and extended half-life up to ~70–100 days compared with motavizumab, while maintaining RSV neutralizing activity in serum for up to 240 days and demonstrating an overall tolerable safety profile.[1][3] The antibody was originally developed by MedImmune (AstraZeneca’s biologics arm) as a long-acting RSV prophylactic, but remains in early-stage investigation and has not been approved for clinical use.[1][7][12]

Other names

Fc-modified motavizumab YTE