The market for myasthenia gravis (MG), an autoimmune and neuromuscular disease characterized by muscle weakness and fatigue, is set to experience a compound annual growth rate (CARG) of 8.3% across the seven major markets (7MM*) from $3 billion in 2022 to $6.7 billion in 2032, forecasts GlobalData, a leading data and analytics company.

GlobalData’s latest report, “Myasthenia Gravis: Opportunity Assessment and Forecast,” identified the influx of several new disease-modifying therapies (DMTs) within the past two years as the main driver of market growth over the forecast period.

Due to their novel mechanisms of action, and positive efficacy and safety profiles, these therapies are expected to improve treatment rates and drive growth within the class II-V MG market*, especially within the treatment refractory segment, in which patients fail to respond to two or more off-label treatments.

Barbora Salcman, Neurology Analyst at GlobalData, comments: “Until 2017, all MG patients were dependant on a range of off-label treatments, such as steroids, immunosuppressants or acetylcholinesterase inhibitors, independent of their diagnosis or MG class. The approval of the first DMT in MG, Alexion’s Soliris (eculizumab), brought a new treatment option for refractory class II-V patients.  Despite its strong efficacy and fast onset, the price mark of nearly $700,000 per year in the US made the DMT inaccessible to many patients due to limited insurance coverage.”

The situation has improved slightly since the approval of Argenx’s Vyvgart (efgartigimod alfa) and Alexion/AstraZeneca’s Ultomiris (ravulizumab), between 2021 and 2022***, as both agents have different mechanisms of action and a lower price mark in comparison to Soliris****. The year 2023 then saw the approval of three new DMTs, namely Argenx’s Vyvgart Hytrulo (efgartigimod alfa + hyaluronidase) and UCB’s Rystiggo (rozanolixizumab-noli) and Zilbrysq (zilucoplan).

Salcman continues: “The approval of five new DMTs in the past two years brings a variety of options to the patients with class II-V MG, as now patients can be prescribed either complement inhibitors or immunoglobulin G (IgG) receptor neonatal Fc receptor (FcRn) inhibitors, with both groups showing good efficacy and safety. There is also a varied route of administration between the DMTs, as some can be administered either subcutaneously or intravenously at the clinic, while Zilbrysq is the first DMT that can be administered subcutaneously by patients themselves.

In terms of the late-stage pipeline, most of the agents in development employ similar mechanisms of action to the recently approved DMTs and none of these are expected to outperform the currently marketed therapies in commercial terms.

Salcman concludes: “Alexion/AstraZeneca’s Ultomiris is expected to be the most profitable agent by 2032, generating sales of around $1.52 billion, followed closely by Argenx’s Vyvgart and Vyvagrt hytrulo with the combined sales of $1.48 billion. This will mainly be due to the agent’s positive efficacy, dosing regimens and their established position on the market.

* 7MM = The US, France, Germany, Italy, Spain, the UK, and Japan.

**The Myasthenia Gravis Foundation of America (MGFA) classification of MG classifies patients from class I-V based on the severity of their symptoms with class I patients only exhibiting ocular symptoms and class V patients requiring intubation to maintain the airway.

***Vyvgart was approved for the use in the US in 2021 and in Europe and Japan in 2022, while Ultomiris was approved in 2022 across the whole 7MM.

****Alexion/AstraZeneca’s Ulomiris is priced at around $490,000 per year, while Argenx’s Vyvgart is priced at around $297,000 per year in the US.