Korro Bio, Inc. has nominated its first development candidate, KRRO-110, for the potential treatment of AATD. KRRO-110 is a proprietary RNA editing oligonucleotide delivered to liver cells using clinically validated LNP technology licensed from Genevant. KRRO-110 is designed to co-opt an endogenous enzyme Adenosine Deaminase Acting on RNA (ADAR) to repair a pathogenic single nucleotide variant (SNV) on RNA and restore production of normal A1AT.

AATD is an inherited genetic disorder caused by SNVs in the SERPINA1 gene that can lead to severe progressive lung disease, including emphysema and chronic obstructive pulmonary disease (COPD), and liver disease. There are an estimated 3.4 million individuals with deficiency allele combinations worldwide. The only current FDA-approved treatment for AATD is augmentation therapy, a once-weekly infusion of pooled human plasma-derived A1AT protein, which does not adequately address the manifestations of AATD.