Beam Therapeutics Inc. presented the recently reported clinical data from the BEAM-302 Phase 1/2 trial in alpha-1 antitrypsin deficiency (AATD) at a symposium on translating scientific discovery in gene editing into clinical progress for patients with lung disease. BEAM-302 is being evaluated in a Phase 1/2, open-label, dose exploration and dose expansion clinical trial to investigate its safety, tolerability, pharmacodynamics, pharmacokinetics and efficacy. Topline data from 29 patients treated with BEAM-302 as of a February 10, 2026 data cutoff date were reported in March 2026.

Dr. Simon's presentation at ATS features additional data for the single-dose cohorts from the same data cutoff, including detailed safety results, efficacy durability and reduction in human neutrophil elastase activity (a direct measure of AAT function) post-BEAM-302 treatment. Based on feedback from the U.S. Food and Drug Administration (FDA), Beam intends to pursue an accelerated approval pathway for BEAM-302. To support a future biologics licensing application (BLA) submission, the company anticipates enrolling approximately 50 additional patients with AATD-associated lung disease, with or without liver disease, in an expansion of the ongoing open-label Phase 1/2 trial.

Beam expects to initiate this pivotal cohort in the second half of 2026. In addition, Beam expects to present detailed and updated BEAM-302 data at a medical congress in 2026. BEAM-302 is a liver-targeting lipid-nanoparticle (LNP) formulation of base editing reagents designed to correct the PiZ mutation.

Patients homozygous for this mutation (PiZZ) represent the majority of patients living with severe AATD disease. A one-time A-to-G correction of the PiZ mutation with Beam?s adenine base editor has the potential to simultaneously reduce the aggregation of mutant, misfolded AAT protein that causes toxicity to the liver (Z-AAT), generate therapeutic levels of corrected protein (M-AAT), and increase total and functional AAT in circulation, thereby addressing the underlying pathophysiology of both the liver and lung disease. In addition, the reduction in circulating PiZ has the potential to further minimize lung inflammation and dysfunction.

Importantly, because BEAM-302 corrects the native AAT gene in its normal genetic location, AAT levels have been observed to increase physiologically in response to infection and inflammation in treated patients. This is a critical aspect of AAT?s normal function to regulate the body?s inflammatory response, which does not occur with currently approved protein replacement therapies. Correction of the PiZ mutation has been durable in patients treated in Beam's clinical trial.