Undisclosed liver-expressed mRNA

Undisclosed liver-expressed mRNA is a placeholder designation used in pharmaceutical pipelines to describe a gene target whose specific identity has not yet been publicly revealed. This terminology is most common in the development of RNA-based therapeutics, such as small interfering RNA (siRNA) or antisense oligonucleotides (ASOs), which are designed to degrade specific mRNA transcripts in hepatocytes. Companies like Arrowhead Pharmaceuticals and Alnylam Pharmaceuticals frequently use this label for early-stage programs or partnered assets (e.g., ARO-JNJ2 and ARO-JNJ3) before the target is formally disclosed. These targets are typically selected for their role in liver-related or systemic diseases, including non-alcoholic steatohepatitis (NASH), chronic hepatitis B, and various metabolic or cardiovascular disorders. The therapeutic approach generally involves the use of GalNAc-conjugation to ensure efficient delivery to the liver, where the drug triggers the RNA interference (RNAi) pathway or RNase H-mediated degradation to silence the expression of a disease-causing protein.

Other names

Undisclosed hepatic mRNA targetUndisclosed liver targetUndisclosed liver-expressed gene

RNA interference (RNAi) or antisense-mediated degradation of the target mRNA transcript, leading to reduced translation and expression of the encoded protein.