244-9-cis is a novel ionizable lipid disclosed in United States Patent US 2026/0014075 A1, specifically engineered for advanced lipid nanoparticle (LNP) delivery systems. Its distinctive molecular architecture features biodegradable ester bonds, which contribute to excellent physicochemical properties such as a near-neutral surface charge (approximately -3 mV) for improved biocompatibility, an optimal pKa of about 6.2 to facilitate endosomal escape, and consistently high nucleic acid encapsulation efficiency exceeding 90%. In vivo studies confirm significantly enhanced delivery to hepatocytes and markedly higher therapeutic protein expression compared to control formulations, positioning 244-9-cis as a promising candidate for next-generation genetic medicines.