Evaluation of ETHY-001 for Safety, Tolerability, and Clinical Activity in Thyroid Eye Disease

Inclusion Criteria:

Parts A and B:

* Body mass index of 18 kg/m2 at screening.
* Agree to comply with all protocol requirements.
* Able to provide written informed consent.
* Agree to defined medications and monitoring as instructed by the site.

Other protocol-defined inclusion criteria will apply.

Part B Only:

\- Must meet the criteria for moderate-to-severe TED.

Exclusion Criteria:

Part A and Part B:

* Significant medical conditions or physical findings that may affect participant safety.
* Active liver or kidney dysfunction at screening.
* Known hypersensitivity to monoclonal antibody products and/or subcutaneous injections.
* Blood pressure or ECG abnormalities at screening.
* Pregnancy of plans for pregnancy; breastfeeding.
* The participant has a history of alcohol or substance abuse within the last 12 months before screening.
* Use of any investigational drug within 60 days prior to the first injection of study drug.
* History of treatment with teprotumumab or other anti-IGF-1R monoclonal antibodies.

Other protocol-defined exclusion criteria apply.