monarsen

Monarsen (EN101) is a 20-mer antisense oligonucleotide (ASO) that selectively targets the mRNA of the readthrough variant of acetylcholinesterase (AChE-R). Unlike standard cholinesterase inhibitors that target all forms of the enzyme, monarsen specifically attenuates the stress-induced accumulation of the soluble AChE-R variant, which is associated with muscle fatigue and proinflammatory signaling. Developed by Ester Neuroscience (later acquired by Amarin), monarsen was investigated as an oral treatment for myasthenia gravis (MG) to improve muscle strength and reduce the need for conventional medications. Clinical studies demonstrated its ability to improve Quantitative Myasthenia Gravis (QMG) scores with a longer duration of action and potentially fewer side effects than traditional small-molecule inhibitors. The drug also showed potential in suppressing proinflammatory cytokines like interleukin-1 (IL-1) and IL-6 in preclinical models.

Other names

Monarsen