Beam reports AATD therapy trial update

• Beam Therapeutics reported updated Phase 1/2 data for BEAM-302 showing increased functional alpha-1 antitrypsin levels in patients with AAT deficiency.
• At the 60 mg dose, mean steady-state total AAT levels increased above the 11 µM protective threshold in lung and liver cohorts.
• Beam Therapeutics has started dosing a global pivotal cohort and plans to pursue a U.S. accelerated approval pathway using 12-month biomarker data.

Beam Therapeutics (NASDAQ:BEAM) reported updated Phase 1/2 data for BEAM-302 showing increased alpha-1 antitrypsin levels and reductions in mutant Z-AAT among patients with alpha-1 antitrypsin deficiency.

The company presented efficacy data from 29 single-dose patients across lung and liver cohorts as of August 17, 2026, with 38 total patients having received BEAM-302.

At the 60 mg dose, mean steady-state total AAT increased from 5 µM to 14.4 µM in the lung cohort and from 4.7 µM to 13.5 µM in the liver cohort, while circulating mutant Z-AAT levels declined by 84% in both groups.

The company reported that BEAM-302 was generally tolerated, with 41% of patients experiencing mostly mild-to-moderate infusion-related reactions and transient liver enzyme elevations, including one Grade 3 ALT/AST event without bilirubin increase or treatment.

Beam Therapeutics is developing gene-editing medicines for genetic diseases and said it has begun dosing a global pivotal cohort using the 60 mg dose while preparing a U.S. accelerated approval pathway.