Inclusion Criteria:  Adult female or male subjects 18 years of age at Screening/Baseline visit (Visit 1) Presence of approximately symmetrical "very thin" lips (minimal red lip shows) to "moderately thick" lips (moderate red lip shows) as assessed with the LFS (severity grade of 1 to 3 on both lips) as determined by the investigator at Visit 1 For females of childbearing potential only: negative urine pregnancy test at Visit 1, and must agree to use an highly effective method of contraception for the duration of the clinical investigation Healthy skin in the treatment area and free of diseases that could interfere in evaluation of treatment Willingness to abstain from any cosmetic or surgical procedures in the treatment area for the duration of the clinical investigation Willingness to take part in this clinical investigation documented by a personally signed/dated informed consent.  Exclusion Criteria:  Pregnancy, lactation, planned pregnancy or unwillingness to use contraception at any time during the study (for women of child-bearing potential only) History of mental disorders or emotional instability History of allergic reaction or hypersensitivity to hyaluronic acid, lidocaine or any amide-based anaesthetic Prior surgery, scars or tattoo to the upper or lower lip or lip line; surgery and tattooing are prohibited until end of clinical investigation Tooth gap, overbite, beard longer three-day beard, or excessive facial hair that could interfere in evaluation of treatment as judged by the investigator Presence of any abnormal lip structure, such as a scar or lump or severe lip asymmetry, as judged by the investigator Previous tissue augmenting therapy in the lip area (including lips, oral commissures, nasolabial folds, marionette and perioral lines) with HA or collagen filler, or laser treatment, chemical peeling, dermabrasion or mesotherapy within 12 months before Visit 1 and until end of clinical investigation Previous permanent implant or treatment with non-HA or non-collagen filler in the lip area (including lips, oral commissures, nasolabial folds, marionette and perioral lines) and until end of the investigation Previous toxin treatment in the lip area (including lips, oral commissures, nasolabial folds, marionette and perioral lines) within 9 months before Visit 1 and until end of clinical investigation Presence of cutaneous lesions, inflammatory and/or infectious processes (e.g. acne, herpes, etc.) or proliferative lesions in the treatment area Known human immune deficiency virus-positive individuals History of allergies against aesthetic filling products and recurrent (3 times a year) herpes simplex in the treated area Tendency to hypertrophic scars, keloid formation and/or pigmentation disorders History or presence of any autoimmune or connective tissue disease, or current treatment with immune therapy Uncontrolled systemic diseases (such as diabetes mellitus) Use of anticoagulant, antiplatelet or thrombolytic medication (e.g. acetylsalicylic acid) from 10 days pre- to three days post IMD injections Planned dental/oral surgery or modification (bridge-work, implants) within two weeks prior to initial IMD injection and to a minimum of four weeks post IMD injections Any medical condition which, in the investigator's opinion, prohibits the inclusion in the study Current or previous (within 30 days of enrolment) treatment with another investigational drug and/or medical device or participation in another clinical study Previous enrolment in this clinical investigation Any dependent relationship of the subject with the investigator, investigation site or Sponsor (e.g. employees or relatives) Subjects whose participation in clinical trials is prohibited by the Austrian Medical Devices Act (e.g., persons with a legal custodian appointed due to mental disability, prisoners, soldiers and other members of the armed forces, civil servants)