Beam picks 60 mg as BEAM-302's optimal dose after topline data and plans a global pivotal cohort

Beam Therapeutics/BEAM-302 (AATD)

Beam chose 60 mg as the optimal dose of BEAM-302, a one-time base-editing treatment that corrects the faulty gene in alpha-1 antitrypsin deficiency. At 60 mg, blood levels of the protective protein reached 16.1 micromolar, above the 11 micromolar protective threshold, with corrected protein comprising 94 percent of total AAT. Beam plans a roughly 50-patient pivotal cohort from H2 2026 aiming for accelerated approval.

• 60 mg optimal dose selected; reached mean 16.1 µM protective AAT protein level (11 µM is protective threshold)
• Corrected M-AAT comprised 94% of total AAT; mutant Z-AAT reduced 84%
• All patients consistently above protective threshold with up to 12 months follow-up
• Pivotal cohort (~50 patients) from H2 2026; pursuing accelerated approval based on 12-month AAT biomarker endpoint