An Open-label Study (OLE) for Non-responders of VRDN-001-101 and VRDN-001-301

Key Inclusion Criteria:

1. Be able to understand the study procedures and the risks involved and be willing toprovide written informed consent before the first study-related activity

2. Have completed at least 5 IV infusions and assessments required to determineproptosis responder status 3 weeks post the fifth IV infusion (i.e., Week 15) asdefined in either the VRDN-001-101 or VRDN-001-301 pivotal studies

3. Been a participant in either the VRDN-001-101 or VRDN-001-301 studies and found tobe a non-responder as defined within the VRDN-001-101 or VRDN-001-301 study

4. Not require immediate surgical ophthalmological or orbital surgery in the study eyefor any reason

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

6. Female TED participants must have a negative urine pregnancy test at screening

7. Be willing and able to comply with all the requirements of the protocol for theentire duration of the study

Key Exclusion Criteria:

Participants must not:

1. Have received prior treatment with another anti-IGF-1R agent

2. Have received systemic corticosteroids for any condition, including TED, or seleniumwithin 2 weeks prior to first dose

3. Have received other immunosuppressive drugs or another investigational agent for anycondition, including TED (other than VRDN-001 or placebo associated with theVRDN-001-101 or VRDN-001-301 pivotal studies), or any other therapy for TED, within 8 weeks prior to first dose

4. Have received radioactive iodine (RAI) treatment within 8 weeks prior to first dose

5. Have had previous orbital irradiation or decompression surgery involving excision offat for TED to the study eye's orbit

6. Have abnormal hearing test before first dose. Have a history of ear conditionsconsidered significant by study doctor