Immunovant Shares Tumble as It Pauses Clinical Dosing of TED Therapy

Rare Daily Staff

Immunovant said it voluntary paused dosing in its ongoing clinical trials for its experimental therapy IMVT-1401 after becoming aware of a physiological signal consisting of elevated total cholesterol and LDL levels in IMVT-1401-treated patients.

Shares of Immunovant fell more than $19.73 to $23.67 in morning trading—a 45 percent decline—in response to the news.

The ASCEND GO-2, a phase 2b trial, is testing IMVT-1401 as a treatment for thyroid eye disease (TED). Cholesterol levels were not measured in prior clinical trials of IMVT-1401 in myasthenia gravis (MG) and in healthy subjects. The company said “Out of an abundance of caution” it has decided to voluntarily pause dosing in ongoing clinical studies in both TED and in warm autoimmune hemolytic anemia, in order to inform patients, investigators, and regulators as well as to modify the monitoring program.

IMVT-1401 is a novel, fully human monoclonal antibody targeting the neonatal Fc receptor. The company believes that this product has the potential to address a variety of IgG-mediated autoimmune diseases as a subcutaneous injection.

ASCEND GO-2 is a randomized, placebo-controlled trial in TED evaluating different doses, each given weekly for 12 weeks. In this study, cholesterol parameters are assessed at baseline, at 12 weeks, and at week 20 following eight weeks off the drug. Based on preliminary, unblinded data from about 40 patients through week 12, mean LDL cholesterol at week 12 increased by approximately 65 percent in the 680 mg dose group, by approximately 40 percent in the 340 mg dose group, and did not increase in the control group.

Average HDL and triglyceride levels increased to a much lesser degree. For context, commercially available statins report a reduction in LDL cholesterol between 27-60 percent. At the twenty-week timepoint, average LDL levels had declined to baseline or lower in the 680 mg dose group, in the 340 mg dose group, and in the control group. No serious cardiovascular events have been reported to date in IMVT-1401 clinical trials.

Harbour BioMed, the license holder for 1401 in Greater China, has informed Immunovant that based on their preliminary review of blinded data in their ongoing clinical studies in Chinese patients with MG and idiopathic thrombocytopenic purpura, similar increases in cholesterol have not been observed. Immunovant said it is not aware whether trials involving other anti-FcRn agents in development have performed detailed assessments of lipid parameters.

The company said it will work with regulators and scientific experts to characterize the detailed profile of these lipid changes and to understand the mechanism of these changes across indications. After discussion and agreement with regulators regarding protocol modifications, the company said it intends to continue to pursue development of IMVT-1401.