New Therapies More Precisely Treat Myasthenia Gravis

Myasthenia gravis is a rare and chronic autoimmune disorder that commonly affects women younger than 40 years and men older than 60 years, and causes muscle weakness impacting the eyes, face, throat, and limbs.

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In 2023, the FDA approved the 2 drugs to treat myasthenia gravis (MG): rozanolixizumab-noli (Rystiggo) was the first for both anti–acetylcholine receptor and anti–muscle-specific kinase antibody-positive MG and zilucoplan (Zilbrysq) was the first for self-administration by a daily injection.

The treatment landscape for MG is expected to continue to change in the coming years due to advances in diagnostics, increased disease awareness, the introduction of emerging therapies, and more, according to a new report from IQVIA.¹

MG is a rare and chronic autoimmune disorder that commonly affects women younger than 40 years and men older than 60 years, but it can affect people of all ages and genders.¹ The condition causes muscle weakness impacting the eyes, face, throat, and limbs.

These symptoms can vary from mild annoyances to more serious afflictions, with some individuals losing the ability to walk, talk, or breath properly, severely impacting their daily living, according to Yale Medicine.²

According to the report, the market for MG treatments is expected to grow with a compound annual growth rate of approximately 17% from 2022 to 2032 as more expensive targeted therapies are developed. Sales are projected to reach approximately $4.1 billion in 2032, up from $1 billion in 2022.¹

From 2022 to 2032, more than 5 new drug launches are expected, and in 2027, the key market leader, eculizumab (Soliris), will lose its patent.¹ Currently there are 5 FDA-approved drugs: eculizumab, efgartigimod alfa (Vyvgart), ravulizumab (Ultomiris), rozanolixizumab, and zilucoplan.

Of note, none of the medications are cures, but they do lessen symptoms. In addition, none of the therapies are totally effective for all patients. Approximately 30% to 40% of patients have no meaningful improvements.²

There are 7 drugs in phase 3 trials: batoclimab, gefurulimab, nipocalimab, satralizumab, cemdisiran, pozelimab, and inebilizumab, according to the report. There are an additional 4 in phase 2 trials (mezagitamab, vemircopan, Descartes-08, and pyridostigmine) and 3 in phase 1 trials (M230, Rlyb116, and CSL730).¹

“Before 2017, there was a significant unmet need for targeted therapies as only symptomatic treatments were available for patients suffering from MG,” the authors wrote.¹ “The landscape of MG treatment is set to change significantly, with new drugs targeting intricate nuances of the body’s immune response.”

Traditionally, acetylcholinesterase (AChE) inhibitors, corticosteroids, and other immunosuppressive drugs have been the standard treatment for MG. AChE inhibitors block an enzyme that breaks down a neurotransmitter that is vital for muscle contraction. AChE inhibitors are the most prescribed first-line treatment for MG. According to IQVIA, this treatment is expected to have high volume but flat sales from 2022 to 2023.¹

Other, new treatments inhibit the neonatal Fc receptor or IL-6 receptors. In addition, a class of drugs can cause B cell depletion, which reduces pathogenic autoantibody production.¹ The focus on targeted therapies will shift treatment to more personalized care.

“Once a blanket diagnosis with a one-size-fits-all treatment approach, MG is now entering an era where its complexity is better understood and more precisely addressed,” the authors wrote.¹

References

1. Bhateja J, Trivedi P. Navigating the shifting landscape of myasthenia gravis treatment: the impact of expensive targeted therapies. IQVIA. January 16, 2024. Accessed January 19, 2024. https://www.iqvia.com/library/articles/navigating-the-shifting-landscape-of-myasthenia-gravis-treatment

2. Katella K. Myasthenia gravis: new drugs and a road to individualized treatment. Yale Medicine. November 13, 2023. Accessed January 19, 2024. https://www.yalemedicine.org/news/myasthenia-gravis-new-drugs-individualized-treatment