The total myasthenia gravis (MG) market was estimated to be worth US$836.5m across the seven major markets (7MM*) in 2018. This is expected to grow at a compound annual growth rate (CAGR) of 8.7% to reach $1.9bn by 2028, according to GlobalData, a leading data and analytics company.

GlobalData’s latest report, ‘Myasthenia Gravis: Opportunity Analysis and Forecasts to 2028’, reveals that the most pressing unmet need in the myasthenia gravis market is the price of biologic drugs, which are the most effective therapies available for patients who suffer from refractory myasthenia; affecting an estimated 17,864 individuals making up 11.7% of diagnosed patients in 2018 in the 7MM. Only four marketed drugs: Tacrolimus, Soliris (eculizumab), Rituxan/MabThera (rituximab) and rituximab biosimilars are specifically used to treat refractory MG.

Magdalene Crabbe, Pharma Analyst at GlobalData, comments: “The four drugs used to treat refractory MG are not accessible for most patients because of how costly they are. Alexion’s Soliris is one of the most expensive drugs in the world, priced at approximately US$678,392 per patient per year.”

The pipeline for MG addresses this need for cheaper therapies and eight late-stage pipeline agents are expected to launch in the 7MM in the forecast period of 2018-2028.

GlobalData anticipates that growth in the MG market will be mainly driven by the entry of two drug candidates in the pipeline; Alexion’s ravulizumab and zilucoplan, developed by Ra Pharma, the biopharmaceutical company recently acquired by UCB.

Crabbe continues: “Although the ACOT of ravulizumab is still high in the US, the rest of the 7MM have lower costs of therapy for both ravulizumab and zilucoplan. These two drugs are expected to be the top-selling late-stage pipeline drugs to launch within the forecast period. In 2028, ravulizumab and zilucoplan are expected to reach sales of $200.6m and $224.4m, respectively.”

These high sales figures are achievable in part because both of these drugs will launch in all 7MM. Although nine other marketed drugs are used to treat all types of MG, there is ample opportunity for pipeline agents to better serve the needs to patients with non-refractory and refractory disease. Ravulizumab and zilucoplan are more likely to be well tolerated among patients compared to marketed drugs like cyclosporine and prednisone, which are associated with unpleasant side effects including infections, diarrhea, hypertension and weight gain.

Crabbe adds: “Understanding the pathophysiology of myasthenia gravis has been a major breakthrough in this field because it has allowed pharmaceutical companies to develop products that can directly target the immune system components that cause the disease in 89.9% of diagnosed patients in the 7MM.”

This improves the likelihood that targeted therapeutic strategies will be effective in treating refractory patients which are the most underserved subpopulation of MG sufferers, given that the condition is an orphan disease.

Crabbe concludes: “Increasing the affordability of safe, effective medicines, is a definite way to improve the prospects for patients.”

*7MM: The US, France, Germany, Italy, Spain, UK and Japan