Argenx Myasthenia Gravis Drug Demonstrates Versatility In Phase III Trial
Data from the Phase III ADAPT-SC study showed that efgartigimod, or VYVGART, administered subcutaneously, achieved the primary endpoint of total IgG reduction from the baseline on the 29th day of observation, establishing itself as a viable option to the intravenously administered efgartigimod alfa-fcab in gMG patients.
SC efgartigimod is made with Halozyme’s ENHANZE drug delivery technology recombinant human hyaluronidase PH20 (rHuPH20). ENHANZE facilitates the subcutaneous injection delivery of biologics that are usually given through IV infusion, thus offering alternative administration routes to meet patient preferences.
“For many years, patients lacked sufficient treatment options, let alone those that were tailored to their unique needs. These data, along with the recent approval of the intravenous formulation, VYVGART, represent exciting advancements in the management of this debilitating, unpredictable disease by offering patients and physicians the option to select treatment based on individual needs and preferences,” commented Dr. James F. Howard Jr., a professor of neurology at the University of North Carolina and principal investigator for the study, in a statement.
Myasthenia gravis is a rare and chronic autoimmune disease where IgG antibodies disrupt the communication between muscles and nerves, leading to muscle weakness. Over 85% of those diagnosed with MG progress to generalized MG within 18 months, characterized by severe muscle weakness, extreme fatigue and motor function disability. In life-threatening cases, MG can affect the muscles needed for breathing.
In the randomized, open-label, parallel-group Phase III ADAPT-SC trial, some 110 adult participants were given 1000mg of efgartigimod-PH20 subcutaneously for 21 days, while others were given the drug through IV (10mg/kg dosage). The pharmacodynamic effect of the drug was then observed one week after the last SC or IV dose was administered.
“Our goal is to redefine and deliver targeted treatment options for people living with gMG globally. By listening to the gMG community, we heard the importance of creating optionality and flexibility for patients. The ADAPT-SC results mark another important step toward achieving this, and further support our vision of delivering a broad array of treatment options for gMG,” noted Tim Van Hauwermeiren, the chief executive of argenx, in the same announcement.
Participants enrolled in the trial are from Japan, Europe and North America. To qualify, each one had to have a confirmed gMG diagnosis and MG-ADL score of at least 5, with over 50% of the total score attributed to non-ocular symptoms at screening and baseline. Before they were randomized, the patients were given a stable dose of at least 1 gMG treatment, plus the necessary corticosteroids, acetylcholinesterase inhibitors and nonsteroidal immunosuppressive drugs.
The total duration of the study was around 12 weeks, including seven weeks of follow-up after the treatment cycle was done. Argenx said that the full details of the study will be presented at a future medical meeting.