Study to Assess Batoclimab in Participants With Active Thyroid Eye Disease

Inclusion criteria:

• Are ≥18 years of age at screening.

• Have a clinical diagnosis of TED associated with active, moderate to severe TED withthe following at screening and Visit 0:

• A CAS ≥ 4 in either eye, and

• Clinical evidence of worsened proptosis with:

1. Proptosis ≥ 18 mm and/or
2. Proptosis ≥ 3 mm increase from participant's baseline (prior to diagnosisof TED), as estimated by the Investigator/assessor

• Have moderate to severe active TED, as defined by European Group on Graves'Orbitopathy (EUGOGO) guidelines.

• Have onset of active TED within 12 months prior to screening.

• Have documented evidence of detectable anti-TSHR-Ab at screening.

• Are not expected to require immediate surgical intervention and are not planningcorrective surgery/irradiation or medical therapy for TED during the course of thestudy.

• Are euthyroid with the baseline disease under control or have mild hypo- orhyperthyroidism.

Additional inclusion criteria are defined in the protocol.

Exclusion criteria:

• Have decreased best corrected visual acuity due to optic neuropathy.

• Have at least a 2-point decrease in CAS or ≥2 mm decrease in proptosis betweenscreening and Baseline assessments in either eye.

• Have used any steroid (intravenous or oral) for the treatment of TED or otherconditions within 4 weeks prior to screening.

• Have used any steroid (Intravenous or oral) with a cumulative dose equivalent to ≥ 1g of methylprednisolone for the treatment of TED.

• Have known autoimmune disease other than TED, that, in the opinion of theInvestigator, would interfere with the course and conduct of the study.

• Had previous orbital irradiation or surgery for TED.

Additional exclusion criteria are defined in the protocol.