A10 (Compound 16) is a diketopiperazine‑based ionizable lipid disclosed in WO 2025/217298 A1 (PCT/US2025/023899) developed by NAVA Therapeutics that enables potent, cell‑selective in vivo delivery of mRNA and nucleic acids without targeting ligands. It forms stable, well‑tolerated lipid nanoparticles (LNPs) that preferentially transfect hematopoietic stem cells (HSCs), bone marrow progenitors, lung epithelium, endothelium, and immune cells while minimizing liver off‑target delivery. In both mice and non‑human primates, A10‑containing LNPs drive functional mRNA expression and gene editing in CD34⁺ HSCs at clinically relevant low doses (0.25–1.0 mg/kg), supporting in vivo HSC gene therapy without ex vivo manipulation.