Thyroid-Stimulating Hormone Receptor (TSHR) Blockade With REGN24493 in Adult Participants With Graves' Disease (GD)

This study will test an experimental Regeneron drug called REGN24493 hereby referred to as "study drug" to see if it can help treat Graves' disease. Graves' disease is a condition where the immune system causes the thyroid gland to make too much thyroid hormone. The main purpose of this study is to learn about the safety of REGN24493 and what side effects it might cause. The study is looking at: * What side effects REGN24493 might cause * How much REGN24493 is in the blood at different times * How REGN24493 affects thyroid hormone levels * If the body reacts to REGN24493 in a way that could affect participant's health * What is the best dose of REGN24493 for treating Graves' disease

Key Inclusion Criteria: 1. Has a diagnosis of Graves' Disease for at least 4 months prior to the screening visit 2. Has thyroid-stimulating hormone receptor antibody (TRAb) level above the upper limit of normal at the screening visit 3. Euthyroid at the screening visit and at least 4 weeks prior to the screening visit as defined in the protocol 4. Body mass index (BMI) between 18.5 and 35.0 kg/m\^2 (inclusive) at the screen visit Key Exclusion Criteria: 1. Has history of hyperthyroidism not caused by Graves' disease (eg, toxic thyroid adenoma, multinodular goiter, amiodarone-induced) 2. Has active thyroid storm or is at current risk of thyroid storm, as assessed by the investigator at the screening visit 3. Has clinically significant cardiac abnormalities attributable to uncontrolled Graves' disease (eg, arrhythmias precipitated by thyrotoxicosis, thyrotoxic cardiomyopathy) 4. Has any infection requiring systemic therapy within the 4 weeks prior to the screening visit 5. Was hospitalized (ie, \>24 hours) for a reason within 30 days of the screening visit that presents any concern to the trial investigator 6. Has used or is using Levothyroxine (LT4) therapy at any dose within 6 weeks of the screening visit 7. Has history of Radioactive iodine (RAI) thyroid ablation or thyroidectomy Note: Other protocol defined Inclusion/Exclusion criteria apply