Orofacial manifestations and microstomia are a frequent complication in systemic sclerosis (SSc) with a major impact on oral hygiene, dental care and quality of life. Peri-oral injection of allogeneic cultured adipose-derived stromal cells constitutes a promising approach to treat scleroderma-induced mouth fibrosis where no alternative therapy is validated. The aim of this phase 2 study is to compare efficacy and safety of perioral injection of allogeneic cultured adipose-derived stromal cells (AdMSC) versus placebo to improve oro-facial fibrosis in patients with systemic sclerosis.

Inclusion Criteria:

• Male or female patient ≥18 years of age,
• Patient with systemic scleroderma according to the 2013 ACR/EULAR classification criteria,
• Mouth Handicap in Systemic Sclerosis Scale (MHISS) score more than or equal to 20 (0-48),
• Rodnan skin score on the face more than or equal to 1,
• Maximal mouth opening of less than 40 mm (distance between the dental arches)
• Patient must have provided written informed consent prior to enrolment,
• Patient must be able to understand their requirements of participating in the protocol.
• Patient affiliated to a social security system.

Exclusion Criteria:

• Patient participating in a clinical trial or having participated in a clinical trial within the previous 3 months,
• Injection of botulinum toxin within 4 weeks prior to "inclusion visit",
• Patient who underwent autologous hematopoietic stem cell transplantation (HSCT) within less than 1 year,
• Local active labial herpes virus within 1 week prior to "inclusion visit",
• Patients with an indication for intensification by autologous HSCT (according to EBMT guidelines and national MATHEC-SFGMTC guidelines),
• History of cancer in the last five years, except for successfully excised basal cell/squamous cell carcinoma, or successfully excised early melanoma of the skin. Subjects, who had a successful tumor resection or radiation or chemotherapy more than 5 years prior to inclusion and no recurrence, may be enrolled in the study,
• Radio- or chemotherapy in progress,
• Females who are pregnant or breastfeeding or plan to be or do so during the course of this study,
• Women of childbearing potential (WOCBP) who are sexually active and unwilling to use an adequate birth control method,
• Vulnerable patient (persons deprived of their liberty by judicial or administrative decision, persons undergoing psychiatric treatment, persons admitted to a health or social establishment for purposes other than research) according to article L1121-6 of the Public Health Code