A Study to Evaluate the Efficacy and Safety of LASN01 in Patients With Thyroid Eye Disease

Inclusion Criteria:

1. Male or female patients ≥18 years of age at the time of Screening

2. Clinical diagnosis of Graves' disease associated with active TED

3. Moderate-to-severe active TED

4. Female patients must be nonpregnant, nonlactating, surgically sterile for ≥6 months,or agree to use a highly effective method of contraception. Males must be surgicallysterile or agree to use a highly effective method of contraception.

5. No previous:

6. Medical treatment for TED, with the exception of:

• Local supportive measures;
• Mycophenolate, and oral or injectable steroids;
• Immunomodulating therapies
• For the open-label treatment arm only: Previous treatment withteprotumumab is required.

2. Orbital surgery

3. Orbital radiation

4. Patients

• Without prior anti-IGF-1R treatment: less than 15 months from onset of TEDsymptoms

• With prior teprotumumab treatment: depending on time of diagnosis orreactivation of disease

Exclusion Criteria:

1. Patients with 2 mm proptosis decrease between Screening and Day 1, or a 1-pointdecrease on the CAS 7-point scale between Screening and Day 1

2. Patients with a known decreased best corrected visual acuity due to optic neuropathyas defined by a decrease in vision of 3 lines on the Snellen chart, new visual fielddefect, or color defect secondary to optic nerve involvement within the last 6months before Screening; or any known optic neuropathy or compression or anyneurologic or neuro-ophthalmologic condition that may result in visual field loss.

3. Previous or any planned orbital irradiation/radiotherapy or orbital surgery for TEDduring the study period (ie, treatment and FU)

4. Use of oral and/or IV corticosteroid for conditions other than TED in the 6 weeksbefore Day 1 (topical steroids for conditions other than TED are allowed)

5. Active autoimmune disorder(s) requiring or likely to require treatment (other thanGrave's disease and TED) that would interfere with study assessments, as determinedby the PI or designee

6. Any previous use of anti-IGF-1R monoclonal antibody (eg, teprotumumab) at any time,with exception to the open-label post-teprotumumab treatment arm where prior use ofteprotumumab is required

7. Use of selenium within 3 weeks before Day 1 or expected use during the clinicaltrial (multivitamins that include selenium are allowed in usual doses)

8. Use or expected use of biotin (including multivitamins that include biotin) within 2days before any laboratory collection