Krystal Biotech announces initial update for KB408, KB407

Krystal Biotech (KRYS) clinical data updates for both KB408 and KB407, the Company’s clinical-stage, inhaled genetic medicine programs in Phase 1 for the treatment of rare respiratory diseases. Today’s updates include molecular data from multiple patients demonstrating SERPINA1 delivery and alpha-1 antitrypsin, AAT, expression within the respiratory tract following KB408 administration as well as safety and tolerability data for both KB407 and KB408 that, taken together, highlight the potential of the Company’s platform to safely deliver genetic cargo to the lung. KB408 for the treatment of alzha-1 antitrypsin deficiency lung disease: Clear evidence of successful gene delivery was observed in both patients, including high rates of transduction and AAT expression in the conducting airways of both patients as assessed via bronchoscopy. patient not on background IV: A clinically meaningful proportion of conducting airway epithelial cells were transduced following administration of a single dose of KB408, with the percentage of cells positive for AAT expression increasing from 0% at baseline to 39% after KB408 dosing. Patient on background IV augmentation: Again, a clinically meaningful proportion of conducting airway epithelial cells were transduced following administration of a single dose of KB408, with the percentage of cells positive for AAT expression increasing from 3% at baseline to 35% after KB408 dosing.