Immunovant’s phase 3 trials of batoclimab fail to meet primary endpoints in thyroid eye disease

Immunovant has announced that its 2 phase 3 trials (GO-1 and GO-2) evaluating batoclimab as an investigational treatment for adults with active, moderate-to-severe thyroid eye disease (TED) failed to meet their primary endpoints.

The primary endpoint in the 2 trials was a ≥2mm proptosis responder rate at week 24, following 12 weeks of high-dose and 12 weeks of low-dose batoclimab treatment. According to the company, no new safety signals were identified, and safety results were consistent with previous findings. The company noted that patients in the TED studies had greater levels of proptosis improvement from baseline after the initial 12-week high-dose period than after the following 12-week low-dose period.

Hyperthyroid patients in the studies showed similar response rates of thyroid hormone normalization to those seen in the batoclimab Phase 2 study in Graves’ disease.

Immunovant, along with partner HanAll, will assess future plans for the development of batoclimab and provide an update at a future, unspecified date.¹

In September 2025,² the company released 6-month off-treatment data in uncontrolled Graves’ disease patients treated with batoclimab for 24 weeks. The study included a 24-week treatment period with a dose step-down followed by a 24-week off-treatment follow-up period. The study included patients with active Graves’ disease as documented by the presence of elevated thyrotropin receptor autoantibodies and hyperthyroid despite ATD therapy. According to the company, at week 48, ~80% (17/21) of patients maintained T3/T4 values less than or equal to the upper limit of normal. Additionally, of the 17 patients, ~50% (8/17) were in ATD free remission, and an incremental ~30% (5/17) were on ATD doses of 2.5 mg/day following 6 months off treatment.

The company also announced it intends to focus on “rapidly advancing” the clinical development of IMVT-1402, an investigational FcRn blocker, in Graves’ disease. Two potentially registrational trials of IMVT-1402 in Graves’ disease will evaluate a 600 mg dose for up to 52 weeks without a step-down in dose. Topline readouts are expected in 2027, according to the company.²

References:

1. Immunovant announces phase 3 study results for batoclimab in Thyroid Eye Disease (TED). Published April 2, 2026. Accessed April 6, 2026. https://www.immunovant.com/investors/news-events/press-releases/detail/81/immunovant-announces-phase-3-study-results-for-batoclimab

2. Immunovant unveils durability and treatment-free six-month remission data with potential to change treatment paradigm for uncontrolled Graves' disease patients. Published September 3, 2025. Accessed April 6, 2026. https://www.immunovant.com/investors/news-events/press-releases/detail/75/immunovant-unveils-durability-and-treatment-free-six-month