Oligonucleotides: Current Trends and Innovative Applications in the Synthesis, Characterization, and Purification

Abstract

Oligonucleotides (ONs) are gaining increasing importance as a promising novel class of biopharmaceuticals. Thanks to their fundamental role in gene regulation, they can be used to develop custom-made drugs (also called N-to-1) able to act on the gene expression at pretranslational level. With recent approvals of ON-based therapeutics by FDA, a growing demand for high-quality chemically-modified ONs is emerging and their market is expected to impressively prosper in the very next future. To satisfy this growing market demand, a scalable and economically sustainable ON production is needed. In this paper, the state of the art of the whole ON production process is illustrated with the aim of highlighting the most promising routes towards the auspicated market-size production. In particular, the most recent advancements in both the upstream stage, mainly based on solid-phase synthesis and recombinant technology, and the downstream one, focusing on chromatographic techniques, are reviewed. Since ON production is projected to expand to the large scale, automatized multi-column technologies will reasonably be required soon to replace the current ones based on batch single-column operations. Cutting edge purification solutions, based on continuous chromatography, will be thus presented in the last part of this review.

Synthesis and Exon-Skipping Properties of a 3′-Ursodeoxycholic Acid-Conjugated Oligonucleotide Targeting DMD Pre-mRNA: Pre-Synthetic versus Post-Synthetic Approach

“…In the frame of our research work aimed at evaluating modified ASO for exon-skipping approaches [11,41], we decided to prepare a 2 OMe PS conjugated at 3 -end with UDCA targeting exon 51 in human DMD. Thanks to the well-established amphiphilic features of BAs, we envisaged of improving physical-chemical and pharmacokinetic properties of ASO 51 by its conjugation to UDCA [35,42,43].…”

Modern trends in downstream processing of biotherapeutics through continuous chromatography: The potential of Multicolumn Countercurrent Solvent Gradient Purification

“…Many of today and tomorrow targeted therapeutics belong to this class. From a wider perspective, thus, the technology has the potential to act as driver for the shift to precision medicine [ 52 ].…”

Modified Nucleosides, Nucleotides and Nucleic Acids via Click Azide-Alkyne Cycloaddition for Pharmacological Applications

“…As such, the possibility of developing drugs that target a single gene or RNA species instead of treating the proteins they are responsible for is thought to be a more attractive approach for various diseases. However, several issues, such as unfavorable cellular uptake, biodistribution, toxicity and size barrier (i.e., oligomers with more than one hundred bases) have limited the clinical development of these strategies [ 47 , 48 ]. Biorthogonal click chemistry represents a promising approach to address several challenges.…”