Efficacy and Safety of Lonigutamab in Subjects With Thyroid Eye Disease (TED)

Key Inclusion Criteria:

- Male or female, ≥18 and ≤70 years of age.

- Proptosis defined in the study eye as ≥3 mm above normal.

- Clinical Activity Score (CAS) ≥4 (using a 7-item scale) for the most severely affected
eye

- Onset of active TED symptoms within 15 months prior to the baseline

- Must agree to use highly effective contraception as specified in the protocol

Key Exclusion Criteria:

- Pathology related to inflammatory bowel disease or irritable bowel syndrome.

- Clinically significant pathology related to hearing or history of hearing impairment

- Optic neuropathy

- Corneal decompensation unresponsive to medical management.

- Previous orbital irradiation (for any cause) or any previous surgical treatment for
TED.

- Subjects with diabetes or hemoglobin A1c >6.0% at screening

- Any steroid use (intravenous [IV] or oral) with a cumulative dose equivalent to >3 g
of methylprednisolone for the treatment of TED within the last year.

- Previous steroid use (IV or oral) specifically for the treatment of TED not to exceed
1 g total dose in the 8 weeks prior to Screening.

- Previous use of teprotumumab or any other IGF-1 receptor (IGF-1R) inhibitor.

- Any previous treatment with a biologic drug for the treatment of TED (eg, rituximab
and tocilizumab)

- Any other immunosuppressive agent within 1 month of screening.