Buy Amondys 45 (casimersen)

What is Amondys 45 (casimersen) for?

Amondys 45 (casimersen) is an antisense nucleotide indicated for the treatment of Duchenne muscular dystrophy (DMD) in patients who have a confirmed mutation of the DMD gene that is amenable to exon 45 skipping.^[1]

It is available in vial form containing 100 mg/2 mL (50 mg/1 mL) casimersen.^[1]

How does Amondys 45 (casimersen) work?

Duchenne muscular dystrophy (DMD) is one of the most common lethal progressive muscle-wasting diseases that is occurring primarily in young boys. In patients with DMD, the protein dystrophin is not functioning properly. Dystrophin is crucial for muscle health, and dysfunctionality of it leads to muscle weakness and loss of muscles.^[2]

This lack of functional dystrophin is caused by a mutation in the dystrophin gene. Most genes are composed of alternating ‘exons’, which contain a genetic code for the production of proteins, and ‘introns’, which do not contain a code. To produce a protein out of this genetic code, the cells make a temporary copy of the gene, called messenger RNA (mRNA). Subsequently, this mRNA will be ‘spliced’, in which the intron regions will be cut out of the mRNA and exons will be fused together, finalizing the complete code for the protein.^[3]

In some cases of DMD, certain parts of the DMD gene are not present, which causes the exons to not fit together properly. This disrupts the code, and leads to the production of a non-functional dystrophin protein.^[3]

Amondys 45 (casimersen) is an antisense oligonucleotide. It contains a piece of artificial mRNA that restores this disruption by fitting the exons together again. Casimersen is designed specifically for exon 45 of the DMD gene, so it is only effective in patients with a mutation that is amenable to exon 45 skipping.^[1]

Where has Amondys 45 (casimersen) been approved?

Amondys 45 (casimersen) was approved for the treatment of DMD patients with a confirmed mutation of the DMD gene that is amenable to exon 45 skipping by:

• The Food and Drug Administration (FDA), USA, on February 25, 2021.^[4]

The FDA approved Amondys 45 (casimersen) under accelerated approval.^[4]

Please note that this medicine may have also been approved in other regions than the ones we’ve listed. If you have a question about its approval in a specific country feel free to contact our support team.

How is Amondys 45 (casimersen) taken?

The standard dosage is:^[1]

• 30 mg/kg administered as an intravenous infusion over 35-60 minutes once weekly.

It is recommended that kidney function is monitored during treatment.^[1]

Complete information about Amondys 45 (casimersen) dosage and administration can be found in the official prescribing information listed in our references section.^[1]

Note: Please consult with your treating doctor for personalised dosing.

Are there any known adverse reactions or side effects of Amondys 45?

Common adverse reactions

The most common adverse reactions (≥20% of patients) listed in the prescribing information include:^[1]

• Upper respiratory tract infection
• Cough
• Pyrexia (fever)
• Headache
• Arthralgia (joint pain)
• Pain in mouth and throat

Serious adverse reactions

The serious adverse reactions listed in the prescribing information include:^[1]

• Kidney damage was observed in animals who received casimersen. Although kidney toxicity was not observed in the clinical studies with casimersen, kidney damage has been observed after administration of some antisense oligonucleotides

Use in a specific population

It is not yet known if Amondys 45 (casimersen) affects an unborn baby.^[1]

For a comprehensive list of side effects and adverse reactions please refer to the official prescribing information.^[1]

References

1. Full prescribing information [FDA]: Amondys 45 (casimersen) [PDF] Sarepta Therapeutics, Inc., Feb 2021

2. Duchenne muscular dystrophy: the basics
Sarepta Therapeutics, last checked on Aug 27, 2020

3. Duchenne muscular dystrophy and dystrophin: pathogenesis and opportunities for treatment
Nowak KJ, EMBO Rep. Sep 5, 2004

4. Sarepta Therapeutics Announces FDA Approval of AMONDYS 45™ (casimersen) Injection for the Treatment of Duchenne Muscular Dystrophy (DMD) in Patients Amenable to Skipping Exon 45
Sarepta Therapeutics press release, Feb 2021