Beam Therapeutics reported updated proof-of-concept data for its base-editing therapy BEAM-302 in alpha-1 antitrypsin deficiency (AATD), saying treatment restored functional protein production and reduced circulating misfolded protein levels in patients. In the ongoing Phase 1/2 study, interim results from 29 participants across three dose cohorts showed functional AAT above a protective threshold and average reductions of more than 80% in misfolded protein. Beam also reported liver enzyme elevations in two patients without symptoms requiring treatment. Beam said it will proceed with its single 60 mg dose and expand the trial later this year, while planning to pursue accelerated approval pathways with the FDA.