Challenges and advances for metabolically stabilizing siRNA

Nucleic Acid Insights 2026; 3(6), 437–453

DOI: 10.18609/nai.2026.053

Published: 4 August
Expert Insight
Theodore‑Carrigan Broda, Ken Yamada

The therapeutic potential of small interfering RNA (siRNA) has been increasingly realized, yet metabolic stabilization remains a central effort to further extend clinical applications and durability of the siRNA drugs. This Expert Insight discusses key considerations for designing metabolic stabilization for siRNA scaffolds, with a focus on understanding degradation mechanisms across biological environments. We examine how nuclease susceptibility, chemical modification patterns, and tissue‑specific factors influence siRNA stability and efficacy. Particular attention is given to maintaining compatibility with Argonaute 2 (AGO2)-mediated RNA interference, as excessive and/or inappropriate positioning of chemical modifications compromises target engagement, RNA‑AGO2 interaction, and thus silencing efficiency. Clinically used and recently advanced chemical modifications are highlighted. Collectively, these insights aim to guide the rational design of next‑generation siRNA therapeutics with improved metabolic stability and clinical performance.


01
How siRNA degrades across tissues and compartments
02
Why the 3′ and 5′ termini are the key stability hotspots
03
Which emerging modifications extend duration of effect
siRNA design
Metabolic stability
AGO2 / RISC
Chemical modification
5′-phosphate mimics
exNA
RNAi therapeutics