The purpose of this study is to demonstrate the efficacy and safety of Restylane Vital Lidocaine when acne scars are treated

Inclusion Criteria:

• Male or female aged 25 to 45 years.
• Caucasian with Fitzpatrick skin type I-III.
• Must be cooperative and willing to comply with the instructions and procedures.
• Provision of signed and dated informed consent to participate in the study.
• Presence of depressed facial atrophic acne scars with a diameter of <4 mm according to at least SCAR-S score 3 category moderate (i.e. more than half of the face involved).

Exclusion Criteria:

• Icepick scarring or atrophic scars with a diameter of ≥4 mm covering more than 25% of the face.
• Active acne with inflammatory component.
• Post-surgical scars in the face.
• History of keloid formation or hypertrophic scars.
• Use of isotretinoin within 12 months of the baseline visit.
• Use of per oral or topical (facial) substances containing retinoids, bensoyl peroxide, alpha-hydroxy acid at a concentration above 10% or beta-hydroxy acid at a concentration above 2% or antibiotics within four months of the baseline visit.
• Concomitant anticoagulant therapy and therapy with inhibitors of platelet aggregation (e.g. aspirin or other nonsteroidal anti-inflammatory drugs [NSAIDs]), Omega-3 or vitamin E seven days before the injection, or a history of bleeding disorders.
• Use of anti-inflammatory agents seven days before the injection.
• History of radiation or skin tumours including actinic keratosis in the face.
• Active skin disease, inflammation or related conditions, such as infection, perioral dermatitis, seborrheic eczema and rosacea in the face.
• History of or active collagen diseases or autoimmune diseases such as systemic lupus erythematous, rheumatic arthritis, skin or systemic sclerosis.
• Previous hypersensitivity to HA.
• Previous hypersensitivity to lidocaine or other amide-type anaesthetics.
• Concomitant treatment with chemotherapy, immunosuppressive agents, immunomodulatory therapy (e.g. monoclonal antibodies), systemic or topical (facial) corticosteroids within 3 months of the baseline visit. (Inhaled corticoids are not an exclusion criterion).
• Presence of facial hair that may interfere with efficacy evaluations.
• Previous tissue augmenting therapy or revitalization treatment in the treatment area with HA or collagen, within 12 months of the baseline visit.
• Permanent implant or treatment with fillers based on other material than HA or collagen in the treatment area.
• Laser, e.g. carbon dioxide and Fraxel, dermabrasion or facial light therapy, e.g. IPL, in the treatment area within 12 months of the baseline visit.
• Chemical peeling in the treatment area within 6 months of the baseline visit.
• Previous surgery in the treatment area.
• Nicotine use within 6 months before the baseline visit.
• Pregnancy or breast feeding.
• Participation in any other clinical study within 30 days before inclusion.
• Any medical condition that in the opinion of the investigator makes the subject unsuitable for inclusion (e.g. severe chronic disease, epilepsy, impaired cardiac conduction, severely impaired hepatic function or severe renal dysfunction).
• Other condition preventing the subject from entering the study in the investigator's opinion, e.g. subjects not likely to avoid other facial cosmetic treatments, subjects anticipated to be unreliable or incapable of understanding the study assessment or unrealistic expectations of treatment result.
• Study staff or close relative of study staff (e.g. parents, children, siblings and spouse).

Adverse events (AEs) were collected by open questioning, information obtained from signs and symptoms detected during examination, observed by study personnel or spontaneous reports from the subjects.