Korro Bio’s shares plunged 81% after topline data from its Phase I/IIa REWRITE trial showed KRRO‑110 produced functional M‑AAT protein but failed to reach the protective 11 µM AAT threshold. The company reported peak total AAT levels well below company projections and lower than rival programs, prompting investor sell‑off. Korro announced a strategic restructuring to extend cash runway into H2 2027, cutting roughly 34% of staff and taking about $2.4 million in one‑time charges. Chief medical officer Olukemi A. Olugemo resigned and will advise for three months; Korro says the departure was not for cause. Management pivoted R&D toward a GalNAc‑conjugated construct slated to enter the clinic in 2027, underscoring how early clinical shortfalls are prompting companies to shift modality or delivery strategies midstream.