Immunovant’s investigational product candidate, IMVT-1401 (formerly known as RVT-1401), is a novel, fully human monoclonal antibody targeting the neonatal Fc receptor (FcRn). We believe that this product has the potential to address a variety of IgG-mediated autoimmune diseases as a subcutaneous injection.
The FcRn receptor facilitates IgG recycling. IMVT-1401 enhances the degradation of IgG by targeting FcRn and preventing endogenous IgG from binding. This increased catabolism of IgG may curtail the harmful immune response exhibited by auto-antibodies.
Immunovant is currently in Phase 2 studies in both MG and TED. We submitted an IND for WAIHA in November 2019. For more information, please visit:
A Study of RVT-1401 in Myasthenia Gravis (MG) Patients
Mechanism of Action
FcRn is the primary protein responsible for preventing the degradation of IgG antibodies and albumin, the most abundant protein found in the blood. The role of FcRn is to bind to the IgG antibodies in the endosome, and transport them to the cell surface, where they are released back into circulation.
IMVT-1401 is designed to selectively bind to and inhibit FcRn, thus blocking the recycling of IgG antibodies.
Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disease characterized by weakness and fatigue of voluntary muscles. The disease is caused by pathogenic antibodies that target the neuromuscular junction, including the acetylcholine receptor and the muscle specific tyrosine kinase receptor, disrupting normal function. MG is a rare disease that affects approximately 46,000 to 66,000 people in the United States. MG is more prevalent in women and tends to affect younger women. In men, MG tends to affect an older population.
The clinical course of MG is variable but usually progressive. Symptoms typically emerge in the eyes (e.g., drooping eyes, double-vision, blurred vision) and progress into the face, throat, and limbs. The chronic nature of MG requires patients to cope with fluctuating symptoms and multiple treatment regimens for management. Overall, the persistent muscle weakness associated with MG often negatively interferes with patients’ ability to engage in daily and physical activities, including demands of work, family, and social functions.
Thyroid Eye Disease
Thyroid eye disease (TED) is an autoimmune disorder that affects the muscles and other tissues around the eyes. TED is most commonly caused by IgG autoantibodies that form against the thyroid-stimulating hormone receptor. These antibodies, which also cause Graves’ disease, activate certain cell types, such as fibroblasts and adipocytes, that are present in the extraocular space, promoting inflammation and cellular expansion that result in the clinical manifestations of the disease. TED has an estimated annual incidence of 16 per 100,000 women and 2.9 per 100,000 men in North America and Europe.
Approximately one in twenty patients with Graves’ disease will present with moderate-to-severe TED that is characterized by swelling and redness of the eyelids, proptosis (protrusion of the eyeball), double vision, and, in severe cases, corneal ulceration and decreased visual acuity. There are no therapies approved by the U.S. Food and Drug Administration for TED.
Warm Autoimmune Hemolytic Anemia
Warm autoimmune hemolytic anemia (WAIHA) is a rare hematologic disease in which autoantibodies mediate hemolysis, or the destruction of red blood cells. The clinical presentation is variable and most commonly includes non-specific symptoms of anemia such as fatigue, weakness, skin paleness, and shortness of breath. Symptoms typically develop chronically over several weeks to months, but rapid progression over a span of days has also been observed. Based on published estimates, we believe that there are approximately 42,000 patients in the United States and 66,000 patients in Europe living with WAIHA.