Korro Bio is attempting to recover after setbacks in its RNA-editing therapy program, as discussed by CEO Ram Aiyar during the J.P. Morgan Healthcare Conference. The company has faced significant challenges since its lead asset, KRRO-110, failed a Phase I/IIa trial for alpha-1 antitrypsin deficiency (AATD) last fall. Following the trial's failure, Korro laid off one-third of its workforce and saw the resignation of its chief medical officer. Novo Nordisk also paused a partnership with Korro for at least a year, leading to an 80% drop in Korro’s stock.
Aiyar explained that after conducting a root-cause analysis over the past three months, the company determined that the lipid nanoparticle (LNP) delivery vehicle used in KRRO-110 was not effective enough. "In every patient we dosed, we saw end protein; it just wasn’t at the levels we needed it to be," Aiyar said. He noted that something specific to AATD patients was causing their construct to degrade—a problem not observed in preclinical models or healthy volunteers.
William Blair analyst Myles Minter commented on Korro’s situation: “If they could work around this issue they would double down likely” on the LNP approach. Instead, Korro is now adopting an N-acetylgalactosamine (GalNac) delivery system similar to those used by other companies in RNA editing for AATD.
Aiyar expressed optimism about moving forward: “now that I know we can make constructs that are three logs more potent.” However, Minter pointed out that starting over with a new formulation puts Korro roughly two years behind competitors such as Wave Life Sciences and Beam Therapeutics.
Aiyar dismissed concerns about being behind: “If the compound is best-in-class, that won’t be a problem.” He referenced his previous experience at Corvidia Therapeutics, which succeeded despite being behind competitors before its acquisition by Novo Nordisk for $2.1 billion in 2020.
Regarding Novo Nordisk's decision to pause its partnership with Korro rather than terminate it outright, Aiyar stated: “They were not in MASH, then they bought Akero,” referring to Novo’s recent $5.2 billion purchase of Akero Therapeutics in October 2025. “I think they’re working through some stuff,” he added. “I’m confident they’ll come back.”
Korro’s financial outlook remains uncertain; layoffs have extended operational viability only into 2027. “We are in a tough cash position to be completely honest,” Aiyar said.
Despite these challenges, Aiyar is seeking new opportunities and partnerships—especially in central nervous system (CNS) programs—and aims to secure funding or collaborations at JPM26. “We have two other shots on goal, other assets” he said, noting interest in further CNS research including discovery-stage ALS programs despite current funding limitations. "We'll look for partners in the CNS space."
