Korro Reports Third Quarter Financial Results, Provides Updates on KRRO-110 in Alpha-1 Antitrypsin Deficiency and Additional Pipeline Programs

Core Insights - Korro Bio, Inc. has provided updates on its Phase 1/2a REWRITE clinical trial for KRRO-110, reported third-quarter financial results, and outlined strategic business decisions [1][5]. Clinical Trial Update - KRRO-110 successfully generated functional M-AAT protein in patients with Alpha-1 Antitrypsin Deficiency (AATD), although the protein levels were below preclinical projections [2][5]. - The REWRITE trial has completed all six planned single ascending dose cohorts in healthy volunteers, with no dose-limiting toxicities observed [4][7]. - The trial is currently evaluating KRRO-110 in two AATD patient cohorts at doses of 0.6 mg/kg and 0.8 mg/kg [4][7]. Development Candidates - Korro has nominated KRRO-121, a GalNAc-conjugated construct aimed at treating hyperammonemia, marking an expansion of its RNA editing platform [3][5]. - The company plans to advance KRRO-121 and a GalNAc version for AATD patients into clinical trials in the second half of 2026 and 2027, respectively [3][5]. Financial Results - As of September 30, 2025, Korro reported cash, cash equivalents, and marketable securities totaling $102.5 million, down from $163.1 million at the end of 2024 [12][26]. - Collaboration revenue for the third quarter of 2025 was $1.1 million, compared to no revenue in the same period of 2024 [13]. - Research and development expenses decreased to $13.8 million from $16.0 million year-over-year, while general and administrative expenses also saw a decline [14][15]. Strategic Restructuring - The company is implementing a strategic restructuring that will reduce its workforce by approximately one-third to focus on generating clinical data and advancing GalNAc-conjugated programs [3][18]. - This restructuring is expected to extend Korro's cash runway into the second half of 2027, with one-time restructuring charges estimated at $2.4 million [18]. Regulatory Milestones - KRRO-110 has received Investigational New Drug clearance from the FDA, along with Fast Track and Orphan Drug Designations [7][19]. - The company is prioritizing high-potential GalNAc-conjugated programs targeting the liver, including KRRO-121 [7][8].