A comprehensive guide to existing and upcoming modalities of nucleic acid therapeutics 

From ASOs and siRNA to circRNA and RNA editing, get a concise, evidence‑based guide to the modalities, chemistries and delivery strategies shaping the next wave of therapies.

Backed by 40+ referenced sources, recent approvals, and real‑world case examples across multiple modalities:

• See the state of play. A clear overview of approved and emerging nucleic acid modalities, with what’s clinically validated and what’s approaching the clinic.
  

• Turn chemistry into performance. Learn how backbone and base modifications (e.g., phosphorothioate, 2’-MOE, LNA) impact stability, specificity and delivery.
  

• Design with fewer blind spots. Understand common pitfalls like off‑targeting, TLR activation and delivery barriers, and how lipid systems, nanoparticles and receptor‑targeted conjugates (e.g., GalNAc) are used to overcome them. 

• Track what’s new and what’s next. From the first CRISPR approvals and saRNA trials to circRNA, cssDNA scaffolds, base/prime editing and tRNA therapies, get a snapshot of near‑term innovation.

What’s inside

Current therapeutics:

• Antisense oligonucleotides (ASOs): Mechanisms (RNase H vs. splice modulation), key modifications (2’-MOE, PS, gapmers), and approved use‑cases (e.g., SMA, DMD, ALS). 

• siRNA: RISC‑mediated silencing, off‑target and innate immune considerations, delivery advances (GalNAc), and an overview of recent FDA approvals. 

• CRISPR‑Cas9: sgRNA design and stabilisation strategies to reduce off‑target effects and cytotoxicity, and the first approvals for haemoglobinopathies. 

• Aptamers: Strengths, clinical reality to date, and how conjugation strategies may unlock broader use. 

• mRNA: Structural elements, stability/immune considerations, and post‑COVID directions including self‑amplifying mRNA and RSV vaccines. 

Future therapeutics in development:

• Circular RNA: Stability advantages, translation‑enabling design, and the first INDs and clinical entries. 

• Circular single‑stranded DNA: Durable scaffolds for aptamers, drug delivery and CRISPR donors; early CAR‑T engineering data. 

• miRNA mimics & inhibitors: Targeting network regulation, current trial status, and LNA‑based specificity gains. 

• Small activating RNA (saRNA): Promoter‑level up‑regulation, emerging oncology trials, and stabilising chemistries. 

• Base & prime editing: dsDNA break‑free precision editing, and first human proof‑of‑concepts. 

• RNA editing: ADAR recruitment to correct pathogenic G→A variants and exon‑editing strategies entering the clinic. 

• tRNA therapies: Read‑through of nonsense mutations as a route to multi‑indication impact, with delivery challenges and early in vivo signals.