Adequate skin hydration is critical for maintaining healthy skin. Moreover, dehydration, together with reduction in cell renewal, loss of radiance, elasticity and firmness, is involved in skin aging. Injectable anti-aging products have been widely used for aesthetic improvement of the skin.

In recent years, new filler products made from High Purification Technology Polynucleotides (PN HPTTM) have been developed and are now being used in Europe. PN HPTTM has a consolidated utilization in the aesthetic field and recently, specific guidelines in their utilization have been implemented. Polynucleotides (PNs) are polymeric chains formed by purines, pyrimidines, deoxyribonucleotides, and deoxyribonucleosides that can be found in cells throughout the human body. PNs have viscoelastic properties and the capability to bind, reorganize and orientate a high concentration of water molecules, creating 3D gel that undergoes an enzymatic cleavage.

On this basis, polynucleotide-containing products act as short-time temporary fillers to produce a volumizing effect and exert a lubricant and moisturizing action, due to the high concentration of water molecules. Moreover, they maintain for a long time the moisturizing and viscoelastic effect.

A recent report which summarizes the findings and recommendations issued from the Italian Scientific Board of aesthetic physicians, supports the use of PN-HPT.

In this context, the Sponsor has developed PN30, a soft-tissue filler containing PN-HPT (at a concentration of 30 mg/ mL) as functional ingredients which help improve skin turgor and elasticity due to their moisturizing and viscoelastic properties.

PN30 is a new device with no history of marketing but based on a similar product CE marked developed and sold by the Manufacturer with less amount of PN (2%). Therefore, the aim of this pre-market, twostages, monocentric, interventional, single-arm, clinical investigation is to evaluate the safety and the performance of PN30 (RDM16) for the improvement of skin hydration. The clinical investigation is planned as an adaptative two-stages study.

The planned procedures will be the same for both stages. The primary objective/endpoint of STAGE I will be to evaluate the safety, while the primary objective/endpoint of STAGE II will be to evaluate the performance of the device.

Inclusion Criteria:

1. Subject Informed consent form (ICF) signed;
2. Female and male Subjects aged 18-70 years;
3. Subjects desiring improvement of skin hydration in maximum 1 area of the face or desiring improvement of skin hydration of neck or décolleté.
4. Healthy skin;
5. Willingness to discontinue all dermatological treatment and procedures during the study;
6. Willingness to follow all study procedures, including attending all site visits, tests and examinations;
7. Agreeing to present at each study visit without face/neck/décolleté cosmetics;
8. Accepting to not change their habits regarding food, physical activity, face/neck/décolleté cosmetics and cleansing products;
9. Willingness to follow indications to avoid make-up in the 12 hours following the injection treatment and to avoid any prolonged exposure to the sun, UV rays and temperatures below 0°C, as well as any sauna or hammam sessions at least until the wheals have been fully reabsorbed;
10. Skin phototype I-IV according to Fitzpatrick's classification.

Exclusion Criteria:

1. Other - different - clinical conditions of the skin (i.e. rosacea, psoriasis, vitiligo, active eczema, severe scleroderma, severe acne and diagnosticated cancer with/without ongoing antitumor therapy);
2. Infectious or inflammatory processes near the area of intervention;
3. Presence of cutaneous disease on the tested area, as malformations and recurrent facial/labial herpes;
4. Presence of tendon, bone or muscular implants near the area of intervention;
5. Ongoing cutaneous allergies;
6. Allergy or contraindications to device components;
7. Concomitant intake of anticoagulant or antiplatelet medications;
8. Subjects who have not followed a washout period of 2 weeks from topical corticosteroids, antibiotics, benzoyl-peroxide, azelaic acid, hydroxy acids, topical retinoids;
9. Immune system illnesses/disease;
10. Uncontrolled diabetes mellitus or uncontrolled systemic diseases (endocrine, hepatic renal, cardiac, pulmonary, neurological disorder);
11. Treatment with substances which act on blood fluidity (eg. Aspirin, NSAIDs, Vitamin E), or drugs able to influence the test results in the investigator opinion, within 5 days prior to study inclusion;
12. Known drug and/or alcohol abuse;
13. Mental incapacity that precludes adequate understanding or cooperation;
14. Any previous permanent and non-permanent cutaneous treatment for aesthetic correction (biomaterial implant, lifting, laser, botulinum toxin injections, chemical peeling, fillers) of the treated area within 6 months prior to study inclusion;
15. Pregnancy or breastfeeding;
16. Participation in another investigational study within 1 month prior to study inclusion.