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Nucleic Acids Research Apr 2023Eighteen nucleic acid therapeutics have been approved for treatment of various diseases in the last 25 years. Their modes of action include antisense oligonucleotides... (Review)
Review
Eighteen nucleic acid therapeutics have been approved for treatment of various diseases in the last 25 years. Their modes of action include antisense oligonucleotides (ASOs), splice-switching oligonucleotides (SSOs), RNA interference (RNAi) and an RNA aptamer against a protein. Among the diseases targeted by this new class of drugs are homozygous familial hypercholesterolemia, spinal muscular atrophy, Duchenne muscular dystrophy, hereditary transthyretin-mediated amyloidosis, familial chylomicronemia syndrome, acute hepatic porphyria, and primary hyperoxaluria. Chemical modification of DNA and RNA was central to making drugs out of oligonucleotides. Oligonucleotide therapeutics brought to market thus far contain just a handful of first- and second-generation modifications, among them 2'-fluoro-RNA, 2'-O-methyl RNA and the phosphorothioates that were introduced over 50 years ago. Two other privileged chemistries are 2'-O-(2-methoxyethyl)-RNA (MOE) and the phosphorodiamidate morpholinos (PMO). Given their importance in imparting oligonucleotides with high target affinity, metabolic stability and favorable pharmacokinetic and -dynamic properties, this article provides a review of these chemistries and their use in nucleic acid therapeutics. Breakthroughs in lipid formulation and GalNAc conjugation of modified oligonucleotides have paved the way to efficient delivery and robust, long-lasting silencing of genes. This review provides an account of the state-of-the-art of targeted oligo delivery to hepatocytes.
Topics: Humans; Morpholinos; Muscular Dystrophy, Duchenne; Oligonucleotides, Antisense; RNA; RNA Interference
PubMed: 36881759
DOI: 10.1093/nar/gkad067 -
Expert Opinion on Drug Metabolism &... Nov 2021Antisense oligonucleotides (ASOs) have emerged as a promising novel drug modality that aims to address unmet medical needs. A record of six ASO drugs have been approved... (Review)
Review
INTRODUCTION
Antisense oligonucleotides (ASOs) have emerged as a promising novel drug modality that aims to address unmet medical needs. A record of six ASO drugs have been approved since 2016, and more candidates are in clinical development. ASOs are the most advanced class within the RNA-based therapeutics field.
AREAS COVERED
This review highlights the two major backbones that are currently used to build the most advanced ASO platforms - the phosphorodiamidate morpholino oligomers (PMOs) and the phosphorothioates (PSs). The absorption, distribution, metabolism, and excretion (ADME) properties of the PMO and PS platforms are discussed in detail.
EXPERT OPINION
Understanding the ADME properties of existing ASOs can foster further improvement of this cutting-edge therapy, thereby enabling researchers to safely develop ASO drugs and enhancing their ability to innovate.
ABBREVIATIONS
2'-MOE, 2'-O-methoxyethyl; 2'PS, 2 modified PS; ADME, absorption, distribution, metabolism, and excretion; ASO, antisense oligonucleotide; AUC, area under the curve; BNA, bridged nucleic acid; CPP, cell-penetrating peptide; CMV, cytomegalovirus; CNS, central nervous system; CYP, cytochrome P; DDI, drug-drug interaction; DMD, Duchenne muscular dystrophy; FDA, Food and Drug Administration; GalNAc3, triantennary N-acetyl galactosamine; IT, intrathecal; IV, intravenous; LNA, locked nucleic acid; mRNA, messenger RNA; NA, not applicable; PBPK, physiologically based pharmacokinetics; PD, pharmacodynamic; PK, pharmacokinetic; PMO, phosphorodiamidate morpholino oligomer; PMOplus, PMOs with positionally specific positive molecular charges; PPMO, peptide-conjugated PMO; PS, phosphorothioate; SC, subcutaneous; siRNA, small-interfering RNA; SMA, spinal muscular atrophy.
Topics: Humans; Morpholinos; Muscular Atrophy, Spinal; Muscular Dystrophy, Duchenne; Oligonucleotides, Antisense; Pharmaceutical Preparations; RNA
PubMed: 34643122
DOI: 10.1080/17425255.2021.1992382 -
Continuum (Minneapolis, Minn.) Dec 2019The dystrophinopathies are among the most common neuromuscular conditions, and they include Duchenne and Becker muscular dystrophies. This article reviews the... (Review)
Review
PURPOSE OF REVIEW
The dystrophinopathies are among the most common neuromuscular conditions, and they include Duchenne and Becker muscular dystrophies. This article reviews the epidemiology, clinical manifestations, genetic cause, management, and new and emerging therapies for this condition.
RECENT FINDINGS
New studies have highlighted how oral corticosteroids have changed the natural history of the disease, prolonging ambulation in boys with Duchenne muscular dystrophy and reducing the risk of developing scoliosis and subsequent surgical correction, improving cardiac health, and increasing long-term survival. Additionally, recent publications have provided insights into how newer and emerging treatment options are becoming more common for this condition. With gene therapy being approved in the United States for the severe form, the dystrophinopathies represent model diseases to understand the personalization of genetic treatment.
SUMMARY
Improvement in the standardization of care and the use of oral corticosteroids have increased the life expectancy of patients with dystrophinopathy and changed the natural history of the disease. This article presents a summary of clinical features, diagnostic testing, and new and emerging treatment strategies for the dystrophinopathies.
Topics: Adrenal Cortex Hormones; Child; Child, Preschool; Humans; Immunologic Factors; Male; Morpholinos; Muscular Dystrophy, Duchenne; Pregnenediones
PubMed: 31794463
DOI: 10.1212/CON.0000000000000791 -
American Journal of Human Genetics Oct 2020Congenital anomalies of the kidney and urinary tract (CAKUT) constitute one of the most frequent birth defects and represent the most common cause of chronic kidney...
Congenital anomalies of the kidney and urinary tract (CAKUT) constitute one of the most frequent birth defects and represent the most common cause of chronic kidney disease in the first three decades of life. Despite the discovery of dozens of monogenic causes of CAKUT, most pathogenic pathways remain elusive. We performed whole-exome sequencing (WES) in 551 individuals with CAKUT and identified a heterozygous de novo stop-gain variant in ZMYM2 in two different families with CAKUT. Through collaboration, we identified in total 14 different heterozygous loss-of-function mutations in ZMYM2 in 15 unrelated families. Most mutations occurred de novo, indicating possible interference with reproductive function. Human disease features are replicated in X. tropicalis larvae with morpholino knockdowns, in which expression of truncated ZMYM2 proteins, based on individual mutations, failed to rescue renal and craniofacial defects. Moreover, heterozygous Zmym2-deficient mice recapitulated features of CAKUT with high penetrance. The ZMYM2 protein is a component of a transcriptional corepressor complex recently linked to the silencing of developmentally regulated endogenous retrovirus elements. Using protein-protein interaction assays, we show that ZMYM2 interacts with additional epigenetic silencing complexes, as well as confirming that it binds to FOXP1, a transcription factor that has also been linked to CAKUT. In summary, our findings establish that loss-of-function mutations of ZMYM2, and potentially that of other proteins in its interactome, as causes of human CAKUT, offering new routes for studying the pathogenesis of the disorder.
Topics: Amphibian Proteins; Animals; Case-Control Studies; Child; Child, Preschool; DNA-Binding Proteins; Epigenesis, Genetic; Family; Female; Forkhead Transcription Factors; Heterozygote; Humans; Infant; Larva; Male; Mice; Mice, Knockout; Morpholinos; Mutation; Pedigree; Protein Binding; Repressor Proteins; Transcription Factors; Urinary Tract; Urogenital Abnormalities; Exome Sequencing; Xenopus
PubMed: 32891193
DOI: 10.1016/j.ajhg.2020.08.013 -
Anchor peptide captures, targets, and loads exosomes of diverse origins for diagnostics and therapy.Science Translational Medicine Jun 2018Exosomes are circulating nanovesicular carriers of macromolecules, increasingly used for diagnostics and therapeutics. The ability to load and target patient-derived...
Exosomes are circulating nanovesicular carriers of macromolecules, increasingly used for diagnostics and therapeutics. The ability to load and target patient-derived exosomes without altering exosomal surfaces is key to unlocking their therapeutic potential. We demonstrate that a peptide (CP05) identified by phage display enables targeting, cargo loading, and capture of exosomes from diverse origins, including patient-derived exosomes, through binding to CD63-an exosomal surface protein. Systemic administration of exosomes loaded with CP05-modified, dystrophin splice-correcting phosphorodiamidate morpholino oligomer (EXO) increased dystrophin protein 18-fold in quadriceps of dystrophin-deficient mdx mice compared to CP05-PMO. Loading CP05-muscle-targeting peptide on EXO further increased dystrophin expression in muscle with functional improvement without any detectable toxicity. Our study demonstrates that an exosomal anchor peptide enables direct, effective functionalization and capture of exosomes, thus providing a tool for exosome engineering, probing gene function in vivo, and targeted therapeutic drug delivery.
Topics: Animals; Cell Line; Exosomes; Inflammation; Mice, Inbred C57BL; Mice, Inbred mdx; Morpholinos; Muscles; Peptides; Serum; Tetraspanin 30
PubMed: 29875202
DOI: 10.1126/scitranslmed.aat0195 -
Handbook of Clinical Neurology 2018Autosomal-recessive proximal spinal muscular atrophy (Werdnig-Hoffmann, Kugelberg-Welander) is caused by mutation of the SMN1 gene, and the clinical severity correlates... (Review)
Review
Autosomal-recessive proximal spinal muscular atrophy (Werdnig-Hoffmann, Kugelberg-Welander) is caused by mutation of the SMN1 gene, and the clinical severity correlates with the number of copies of a nearly identical gene, SMN2. The SMN protein plays a critical role in spliceosome assembly and may have other cellular functions, such as mRNA transport. Cell culture and animal models have helped to define the disease mechanism and to identify targets for therapeutic intervention. The main focus for developing treatment has been to increase SMN levels, and accomplishing this with small molecules, oligonucleotides, and gene replacement has been quite. An oligonucleotide, nusinersen, was recently approved for treatment in patients, and confirmatory studies of other agents are now under way.
Topics: Animals; Humans; Morpholinos; Muscular Atrophy, Spinal; Mutation; Oligonucleotides; Survival of Motor Neuron 1 Protein; Survival of Motor Neuron 2 Protein
PubMed: 29478602
DOI: 10.1016/B978-0-444-64076-5.00038-7 -
Current Pharmaceutical Biotechnology 2022The dramatically increasing levels of antibiotic resistance are being seen worldwide and are a significant threat to public health. Antibiotic and drug resistance is... (Review)
Review
The dramatically increasing levels of antibiotic resistance are being seen worldwide and are a significant threat to public health. Antibiotic and drug resistance is seen in various bacterial species. Antibiotic resistance is associated with increased morbidity and mortality and increased treatment costs. Antisense-related technologies include oligonucleotides that interfere with gene transcription and expression; these oligonucleotides can help treat antibiotic-resistant bacteria. The important oligonucleotides include Peptide Nucleic Acids (PNAs), Phosphorodiamidate Morpholino Oligomers (PPMOs), and Locked Nucleic Acids (LNAs). Typically, the size of these structures (oligonucleotides) is 10 to 20 bases. PNAs, PPMOs, and LNAs are highlighted in this review as targets for genes that cause the gene to be destroyed and impede bacterial growth. These results open a new perspective for therapeutic intervention. Future studies need to examine different aspects of antisense agents, such as the safety, toxicity, and pharmacokinetic properties of antisense agents in clinical treatment.
Topics: Anti-Bacterial Agents; Morpholinos; Peptide Nucleic Acids; Oligonucleotides, Antisense; Bacteria; Oligonucleotides
PubMed: 35034590
DOI: 10.2174/1389201023666220114160216 -
Annals of Neurology Jan 2017
Topics: Humans; Morpholinos; Muscular Dystrophy, Duchenne
PubMed: 27997029
DOI: 10.1002/ana.24843 -
Journal of Neuromuscular Diseases 2021BackgroundEteplirsen received accelerated FDA approval for treatment of Duchenne muscular dystrophy (DMD) with mutations amenable to exon 51 skipping, based on...
BackgroundEteplirsen received accelerated FDA approval for treatment of Duchenne muscular dystrophy (DMD) with mutations amenable to exon 51 skipping, based on demonstrated dystrophin production.ObjectiveTo report results from PROMOVI, a phase 3, multicenter, open-label study evaluating efficacy and safety of eteplirsen in a larger cohort.MethodsAmbulatory patients aged 7-16 years, with confirmed mutations amenable to exon 51 skipping, received eteplirsen 30 mg/kg/week intravenously for 96 weeks. An untreated cohort with DMD not amenable to exon 51 skipping was also enrolled.Results78/79 eteplirsen-treated patients completed 96 weeks of treatment. 15/30 untreated patients completed the study; this cohort was considered an inappropriate control group because of genotype-driven differences in clinical trajectory. At Week 96, eteplirsen-treated patients showed increased exon skipping (18.7-fold) and dystrophin protein (7-fold) versus baseline. Post-hoc comparisons with patients from eteplirsen phase 2 studies (4658-201/202) and mutation-matched external natural history controls confirmed previous results, suggesting clinically notable attenuation of decline on the 6-minute walk test over 96 weeks (PROMOVI: -68.9 m; phase 2 studies: -67.3 m; external controls: -133.8 m) and significant attenuation of percent predicted forced vital capacity annual decline (PROMOVI: -3.3%, phase 2 studies: -2.2%, external controls: -6.0%; p < 0.001). Adverse events were generally mild to moderate and unrelated to eteplirsen. Most frequent treatment-related adverse events were headache and vomiting; none led to treatment discontinuation.ConclusionsThis large, multicenter study contributes to the growing body of evidence for eteplirsen, confirming a positive treatment effect, favorable safety profile, and slowing of disease progression versus natural history.
Topics: Adolescent; Child; Disease Progression; Dystrophin; Exons; Humans; Male; Morpholinos; Muscular Dystrophy, Duchenne; Mutation; Vital Capacity
PubMed: 34120909
DOI: 10.3233/JND-210643 -
Methods in Cell Biology 2019MicroRNAs (miRNAs) are small non-coding RNAs that repress the translation and reduce the stability of target mRNAs in animal cells. Post-transcriptional regulation... (Review)
Review
MicroRNAs (miRNAs) are small non-coding RNAs that repress the translation and reduce the stability of target mRNAs in animal cells. Post-transcriptional regulation mediated by miRNAs is a highly conserved mechanism utilized by organisms throughout phylogeny to fine tune gene expression. We document the approaches used to study the function of a single miRNA and miRNA regulation of biological pathways in the sea urchin embryo. The protocols that are described include selection of miRNA inhibitors, test of miRNA direct targets, and the use of target protector morpholinos to evaluate the impact of miRNA inhibition on its targets. Using the described techniques and strategies, the sea urchin researcher will be able to validate a miRNA's direct targets and evaluate how inhibition of the miRNA affects developmental processes. These results will contribute to our understanding of the regulatory roles of miRNAs in development.
Topics: Animals; Embryonic Development; Gene Expression Regulation, Developmental; MicroRNAs; Morpholinos; RNA, Messenger; Sea Urchins; Signal Transduction; Transcription Factors
PubMed: 30948016
DOI: 10.1016/bs.mcb.2018.10.005