A Study to Investigate the Efficacy and Safety of Rilzabrutinib in Adult Participants With Graves' Disease

This is a parallel group, Phase 2, 2-arm study to measure the treatment effect and safety of rilzabrutinib dose 1 or rilzabrutinib dose 2 in participants with Graves' disease, with and without Graves' orbitopathy, aged 18 years or older.

Study details include:

• Screening period (up to 4 weeks).
• Treatment period (up to 16 weeks).
• Follow-up period (4 weeks). The number of visits will be up to 13.

Inclusion Criteria:

• Participants who have a confirmed diagnosis of Graves' disease with active hyperthyroidism, with or without active Graves' orbitopathy at the time of screening.
• A subset of participants will have a diagnosis of active Graves' orbitopathy, as confirmed by ophthalmic exam at screening and a clinical activity score (CAS) ≥3 for the most severely affected eye, and associated with one or more of the following: lid retraction ≥2 mm, moderate or severe soft tissue involvement, proptosis ≥2 mm, and/or intermittent or constant diplopia.
• Contraceptive use by men and women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies.

Exclusion Criteria:

• History of hyperthyroidism not caused by Graves' disease (eg, hyperthyroidism due to toxic multinodular goiter, autonomous thyroid nodule, acute inflammatory thyroiditis).
• History of thyroid storm or at high risk of developing thyroid storm as determined by evaluating clinician.
• Enlarged thyroid goiter causing upper airway obstruction and/or requiring surgical intervention during the study period.
• For participant with Graves' orbitopathy, requires immediate surgical ophthalmological intervention or is planning corrective surgery/irradiation during the course of the study.
• Sight threatening Graves' orbitopathy or decreased visual acuity due to optic neuropathy within the last 6 months.
• Corneal decompensation unresponsive to medical management.
• Onset of Graves' orbitopathy symptoms >9 months prior to baseline.

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.