• Participant must fulfill the 2013 American College of Rheumatology/ European League Against Rheumatism classification criteria for systemic sclerosis and meet the diffuse cutaneous SSc (dcSSc) subset classification according to LeRoy.

• Disease onset from the first non-Raynaud symptoms attributable to SSc (e.g., puffy hands, scleroderma, digital ulcers, arthralgia, dyspnea) within 7 years prior to the Screening visit.

• Severe, progressive systemic sclerosis disease defined by at least one of the following:

‣ Progressive systemic sclerosis-associated interstitial lung disease

⁃ Severe, progressive systemic sclerosis skin disease

⁃ Clinically significant systemic sclerosis-associated cardiac involvement at Screening