Immunovant’s first-generation FcRn inhibitor flunked a pair of phase 3 eye disease trials, appearing to end the last hopes of commercializing the drug.
The company set out plans back in 2022 to assess the therapy, called batoclimab, in two late-stage studies of patients with thyroid eye disease (TED). This morning, Immunovant’s majority shareholder Roivant revealed that both trials had missed their primary endpoint of demonstrating a 2 mm or greater reduction in proptosis—a term for eye bulging—after 12 weekly doses of high-dose batoclimab followed by 12 weeks of a low dose.
Patients in the studies were randomized to receive either the treatment or placebo. No new safety signals were identified, Roivant noted.
The company pointed out that greater improvements in proptosis were seen after the high-dose period than after the low-dose period. This “support[s] the benefit of deeper IgG suppression,” Roivant concluded. TED is an immunoglobulin G (IgG)-mediated autoimmune condition.
When looking specifically at hyperthyroid patients, Roivant said that batoclimab demonstrated similar rates of thyroid hormone normalization to those seen in a phase 2 study of the therapy in Graves’ disease, a condition that leads to TED.
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Batoclimab did score a phase 3 win in March 2025 in myasthenia gravis, another IgG-driven disorder. But by that point Immunovant had decided not to commercialize batoclimab in this condition. While it already sounded like Immunovant had lost enthusiasm for the asset, the company said at the time that it was holding off making a decision on whether to pursue batoclimab in TED until it saw today’s phase 3 results.
The following month, batoclimab’s future sounded even bleaker. As Roivant took tighter control of the spinout by installing its own CEO, the company explained that development activities for the asset could “begin to conclude.”
According to this morning’s release, Immunovant now “intends to review future plans for the development of batoclimab” with its Korea-based partner HanAll and provide an update “at a future date.”
TED can cause muscles that control the eye and fat behind the organ to grow abnormally, and it can also lead to orbital inflammation. This can in turn cause proptosis, double vision or, in severe cases, vision loss.
This morning’s double trial failure is another blow to attempts to get a FcRn inhibitor approved for TED after argenx discontinued studies of Vyvgart for the eye condition after they appeared set to miss their goal.
Under a closer alignment with Roivant, Immunovant has been focusing its resources on a a second-generation FcRn blocker dubbed IMVT-1402. Topline data from phase 2b studies of IMVT-1402 in Graves’ disease are expected next year, Roivant confirmed in this morning’s release.
