Following the news that the FDA has approved Argenx’s subcutaneous formulation of efgartimod alfa, branded as Vyvgart Hytrulo, for use in myasthenia gravis (MG);

Barbora Salcman, Neurology Analyst at GlobalData, offers her view:

“The approval comes after a period of uncertainty and extends the availability of Vyvgart to acetylcholine receptor autoantibody positive (AChR+) patients diagnosed with generalized MG, who were previously treated with the intravenous (IV) form of the medication. The intravenous (IV) form of Vyvgart has been approved to treat MG since 2021 in the US market and 2022 in European and Japanese markets. Vyvgart Hytrulo targets the same population as its IV version, who are AChR+ patients diagnosed with generalized MG.

“Not only was IV Vyvgart the first neonatal Fc receptor blocker to be marketed for use in MG patients, now it is also the first disease-modifying therapy to be available for subcutaneous administration for these patients. This approval is a significant event for patients diagnosed with generalized MG as all the medication currently approved to be used in the treatment of MG are only given in the form of IV, tackling the unmet need for other forms of agent administration.

“Since 2022, the medication has been in direct competition with AstraZeneca’s Ultomiris, a next-generation IV C5 complement inhibitor, as both agents exhibit promising efficacy profiles. While IV Ultomiris has a more convenient dosing regimen than IV Vyvgart (Ultomiris is administered every 8 weeks, while Vyvgart is administered every 4 weeks), Vyvgart exhibits a better safety profile, as Ultomiris comes with a boxed warning for serious meningococcal infections.

“The approval of a subcutaneous formulation of Vyvgart has the potential to significantly skyrocket the drug ahead of its competition by making the treatment more convenient for patients. However, Vyvgart may not always have this advantage. Ultomiris has been approved for subcutaneous use in paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome, therefore it is expected that AstraZeneca will also seek approval in the MG indication.

“Argenx has not yet published the price of the Vyvgart Hytrulo.  In the US market, IV Vyvgart is priced at around $225,000 per year, while Ultomiris is priced at around $458,000 per year. The lower price of Vyvgart in comparison to its competition is an advantage for Argenx, making it more likely that insurance providers will reimburse the cost. We will see if there is a similar price difference for the subcutaneous form.”

A decision on the marketing authorization for the use of Vyvgart Hytrulo in the European market is expected to be known by the end of 2023 and in Japan in Q1 of 2024.