Systemic Sclerosis (SSc) Clinical Trials

• Diagnosis of diffuse cutaneous systemic sclerosis, classified according to 2013 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR)

• Participant is either:

∙ Within 2 years of their first non-Raynaud's symptom and their mRSS is \>7; OR

‣ \>2 and ≤5 years from their first non-Raynaud's symptom, their mRSS is between 10 and 30, they are negative for the RNA polymerase 3 autoantibody, and (1) they have never had any previous spontaneous improvement in skin thickening of ≥4 points by mRSS on exams performed by the same clinician, or (2) they were never clinically noted to have a meaningful spontaneous reduction in skin thickness if mRSS was never done; OR

‣ \>5 and ≤10 years from their first non-Raynaud's symptom, their mRSS is between \>15 and ≤25, they are negative for the RNA polymerase 3 autoantibody, and (1) they have never had any previous spontaneous improvement in skin thickening of ≥4 points by mRSS, or (2) were never clinically noted to have a meaningful spontaneous reduction in skin thickness if mRSS was never done.

• Participant is ≥18 years of age at time of signing the ICF.

• Able to understand the study and provide a signed, written ICF

• Able to read and understand the language of the ICF and other study-related materials

• Forced vital capacity (FVCpp) of ≥45 pp10

• Have diffusing capacity of the lungs for carbon monoxide (DLCO) of ≥30 percent predicted at Screening

• Willing and able to complete all protocol-required study visits and procedures

• Participants of childbearing potential must have a negative serum pregnancy test at Screening.

⁃ All participants with reproductive potential must agree to use and follow medically approved, highly effective methods of contraception during treatment and until 5 half-lives or 125 days after the last dose, whichever is longer