4D-A101

4D-A101 is a proprietary engineered **adeno-associated virus capsid vector** developed by 4D Molecular Therapeutics for pulmonary gene delivery. It is not a standalone approved medicine or brand, but a customized delivery vehicle used in the company's aerosolized genetic medicine programs, most notably 4D-710 for cystic fibrosis and 4D-725 for alpha-1 antitrypsin lung disease. The vector was identified through directed evolution to improve airway transduction after aerosol administration, with reported resistance to pre-existing anti-AAV neutralizing antibodies and the ability to drive broad gene transfer across the lung epithelium. In clinical development, its therapeutic effect depends on the payload transgene it carries rather than on intrinsic pharmacology of the capsid itself.

Other names

A101 AAV vectorA-101 AAV vectorA 101 AAV vector