BEAM-302

BEAM-302 is a liver-targeting lipid nanoparticle (LNP) formulation containing a guide RNA and an mRNA encoding an adenine base editor. It is designed for in vivo base editing to correct the PiZ mutation (E342K) in the SERPINA1 gene, which causes alpha-1 antitrypsin deficiency (AATD). This one-time therapy aims to make a single A-to-G correction at the DNA level, reducing misfolded Z-AAT protein aggregation that leads to liver toxicity, generating therapeutic levels of corrected M-AAT protein, and increasing total and functional AAT in circulation. By correcting the underlying genetic defect at its native locus, BEAM-302 enables physiological regulation of AAT production—something not possible with current protein replacement therapies. Early clinical data show durable, dose-dependent increases in functional AAT above protective thresholds and reductions in mutant Z-AAT after a single infusion. The drug is being developed by Beam Therapeutics and is currently under investigation in Phase 1/2 trials for both lung and liver manifestations of AATD[1][3][4][5][6][8].