Casimersen (AMONDYS 45™): An Antisense Oligonucleotide for Duchenne Muscular Dystrophy

• Published in: Biomedicines Vol. 12; no. 4; p. 912
• Main Authors: Assefa, Milyard, Gepfert, Addison, Zaheer, Meesam, Hum, Julia M, Skinner, Brian W
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01-04-2024
• Subjects: Age; AMONDYS 45; antisense oligonucleotide; Antisense oligonucleotides; Antisense therapy; casimersen; Clinical trials; CRISPR; Duchenne muscular dystrophy; Duchenne's muscular dystrophy; Dystrophin; exon skipping; FDA approval; Females; Fomivirsen; Immune system; Males; Mipomersen; mRNA; Muscular dystrophy; Mutation; Myocytes; Pathophysiology; Pegaptanib; Point mutation; Proteins; Steroids; X chromosomes; phosphorodiamidate oligomer; antisense oligonucleotide; exon skipping; Duchenne muscular dystrophy; neuromuscular disorders; casimersen; dystrophin; AMONDYS 45
• ISSN: 2227-9059; 2227-9059
• DOI: 10.3390/biomedicines12040912

Casimersen (AMONDYS 45
) is an antisense oligonucleotide of the phosphorodiamidate morpholino oligomer subclass developed by Sarepta therapeutics. It was approved by the Food and Drug Administration (FDA) in February 2021 to treat Duchenne muscular dystrophy (DMD) in patients whose
gene mutation is amenable to exon 45 skipping. Administered intravenously, casimersen binds to the pre-mRNA of the
gene to skip a mutated region of an exon, thereby producing an internally truncated yet functional dystrophin protein in DMD patients. This is essential in maintaining the structure of a myocyte membrane. While casimersen is currently continuing in phase III of clinical trials in various countries, it was granted approval by the FDA under the accelerated approval program due to its observed increase in dystrophin production. This article discusses the pathophysiology of DMD, summarizes available treatments thus far, and provides a full drug review of casimersen (AMONDYS 45
).