The primary objective of the study is to assess the change in systemic sclerosis (SSc)-associated gastrointestinal (GI) tract symptoms over a 1-year period in participants with SSc.

No study treatment will be administered. Study participants will continue to be treated by their respective physicians according to standard clinical practice. Data on concomitant therapy and procedures, administered as part of standard of care, will be collected at baseline and at each study visit.

Key Inclusion Criteria:

Healthy volunteers

• Must be in good health as determined by the Investigator, based on medical history, physical examination, and vital signs.

Participants with diffuse cutaneous systemic sclerosis (dcSSc):

• Must fulfill the 2013 classification criteria for SSc of the American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR).
• Absence of the anti-centromere autoantibody.

Participants with limited cutaneous systemic sclerosis (lcSSc):

• Must fulfill the 2013 classification criteria for SSc of the ACR and EULAR.
• Subjects with lcSSc must have disease duration of less than 5 years.

Key Exclusion Criteria:

• History of any clinically significant medical condition that can interfere with the conduct of the study, or that in the opinion of the Investigator, would compromise data interpretation.
• An active severe infection as determined by the Investigator.
• Female subjects who are pregnant or currently breastfeeding.
• A known history of malignancy.

NOTE: Other protocol defined Inclusion/Exclusion criteria may apply

Study participants will be recruited at participating locations in a standard clinical practice setting.