ABSTRACT
In recent years, antisense oligonucleotide (ASO) has been very active in the field of rare disease research and development, especially in Duchenne muscular dystrophy, where it made a major breakthrough. Duchenne muscular dystrophy (DMD) is a rare childhood myopathy caused by mutations in the dystrophin gene. Currently, the four ASO drugs approved internationally for DMD are all targeted at dystrophin, including eteplirsen, golodirsen, viltolarsen and casimersen. They all belong to phosphorodiamidate morpholino oligomers (PMO) antisense oligonucleotide drugs, so that their pharmacokinetic characteristics are similar. The drugs quickly spread to other tissues after intravenous administration. Because of the electrical neutrality of the PMO, they have a low binding rate to plasma proteins and are quickly metabolized by the kidney and excreted in the urine as archetypes. In addition, the likelihood of drug-drug interactions of ASO is low. Existing clinical studies have shown that they have certain clinical benefits and good tolerability, bringing new options for DMD treatment. This paper mainly discusses the pharmacological effects, pharmacokinetic characteristics, efficacy, and safety of ASO drugs for the treatment of DMD, hoping to provide scientific reference for the rational and safe clinical use of such drugs.
ABSTRACT
Because many therapeutic agents are contaminated by epimeric impurities or form epimers as a result of metabolism, analytical tools capable of determining epimers are increasingly in demand. This article is a proof-of-principle report of a novel DMS-MS/MS method to separate and simultaneously quantify epimers, taking PGF2 and its 8-epimer, 8--PGF2, as an example. Good accuracy and precision were achieved in the range of 10-500 ng/mL with a run time of only 1.5 min. Isopropanol as organic modifier facilitated a good combination of sensitivity and separation. The method is the first example of the quantitation of epimers without chromatographic separation.