Poly-L-lactic Acid (PLLA) Injection for Neck Skin Laxity: A Pilot Study

The Efficienctiveness of Poly-L-Lactic Acid, PLLA for the Treatment of Skin Laxity of the Neck: A Pilot Study

Skin aging of the neck commonly leads to wrinkles and skin laxity due to the gradual loss of collagen and structural support in the skin. Although several treatments are available, effective non-surgical options for improving neck skin laxity remain limited. This pilot study aims to evaluate the effectiveness and safety of Poly-L-Lactic acid (PLLA) injections for improving neck skin laxity.

Study Overview

• Status: Not yet recruiting
• Conditions: Skin Aging; Wrinkles
• Intervention / Treatment: Drug: Poly-L-Lactic Acid (Sculptra) injection

Detailed Description

This study is a prospective pilot interventional study designed to evaluate the effectiveness and safety of Poly-L-Lactic acid (PLLA) injections for the treatment of neck skin laxity. Eligible Thai male and female participants aged 30 to 60 years with neck skin laxity grades 1 to 4 according to the Neck Skin Laxity Scale (NSL scale) will be enrolled. Participants will receive a single treatment session of PLLA injection to the neck using a cannula technique in the subcutaneous plane with a linear retrograde fanning method through lateral entry points. Approximately 8 mL of PLLA solution will be injected on each side of the neck, for a total volume of 16 mL per participant. Clinical outcomes will be evaluated at baseline and during follow-up visits at weeks 8, 16, and 24. Outcome measures include improvement in neck skin laxity assessed using the NSL scale, changes in skin elasticity measured by using the Cutometer® Dual MPA 580, participant satisfaction, and treatment-related adverse events. Outcome assessment will be performed by comparing follow-up measurements with baseline values.

• Study Type: Interventional
• Enrollment (Estimated): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Thailand
  • Bangkok
    • Ratchathewi, Bangkok, Thailand, 10400
      • Institute of Dermatology
      • Contact: Medical Sciences (Dermatology); Phone Number: +6623545222; Email: dr_tanongkiet@yahoo.com
      • Contact: Tanongkiet Tienthavon; Phone Number: +66952072833

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Thai male or female participants aged 30-60 years
• Individuals who wish to improve neck skin laxity
• Presence of neck skin laxity grade 1-4 according to the Neck Skin Laxity Scale (NSL scale)

Exclusion Criteria:

• Pregnant or breastfeeding women
• History of allergy or hypersensitivity to local anesthetics or components of collagen-stimulating substances
• Active autoimmune disease requiring systemic treatment
• History of cosmetic procedures in the neck area, including laser treatment, radiofrequency, or ultrasound-based devices within 6 months prior to treatment
• History of dermal filler injection in the neck area
• History of botulinum toxin injection in the neck area within 6 months prior to treatment

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: PLLA Injection; Participants will receive a single treatment session of Poly-L-Lactic acid (PLLA) injection for the treatment of neck skin laxity. PLLA will be administered to the neck using a cannula technique in the subcutaneous plane. Approximately 16 mL of PLLA solution will be injected per participants. Clinical outcomes will be evaluated at baseline and during follow-up visits at Weeks 8, 16, and 24.

Drug: Poly-L-Lactic Acid (Sculptra) injection; Poly-L-Lactic acid (PLLA) is used as a collagen-stimulating injectable for the treatment of neck skin laxity. The PLLA solution is prepared by reconstituting PLLA with sterile water and lidocaine to a total volume of 16 mL. Participants will receive a single treatment session of PLLA injection to the neck using a cannula technique. The injection is performed in the subcutaneous plane using a linear retrograde fanning technique through lateral entry points of the neck. Approximately 8 mL of PLLA solution will be injected on each side of the neck (total 16 mL per participant). Clinical outcomes will be assessed at weeks 8, 16, and 24.; Other Names: Sculptra; PLLA

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Neck Skin Laxity Scale (NSL scale) Score	Neck skin laxity will be evaluated using standardized clinical photographs captured with the VECTRA® image system. Blinded dermatologists will assess neck skin laxity using NSL Scale at baseline (Week0), Week 8, Week 16, and Week 24. The NSL Scale is a 5-point ordinal scale ranging from 0 to 4, where : 0 = Absent : No visible neck skin laxity.; = Mild : Minimal skin laxity with slight loss of firmness and subtle horizontal lines.; = Moderate : Noticeable skin laxity with visible horizontal lines and mild skin redundancy.; = Advanced : Marked skin laxity with prominent folds, visible skin redundancy, and moderate loss of neck contour.; = Severe : Severe skin laxity characterized by extensive redundant skin, deep folds, wrinkles, and substantial loss of neck contour. Higher scores indicate greater neck skin laxity and a worse aesthetic appearance, while lower scores indicate less neck skin laxity and improvement in neck appearance.	Baseline (Week 0), Week 8, Week 16, and Week 24

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Participant-Reported Neck Appearance Satisfaction Score Assessed Using the 5-Point Neck Appearance Satisfaction Scale	Participant-reported satisfaction with neck appearance following PLLA treatment will be assessed at baseline (Week 0), Week 8, Week 16 and Week 24 using a 5-point Neck Appearance Satisfaction Scale. The scale ranges from 1 to 5, where : = Very dissatisfied; = Dissatisfied; = Neutral; = Satisfied; = Very satisfied Higher scores indicate greater participant satisfaction with neck appearance following treatment.	Baseline (Week 0), Week 8, Week 16, and Week 24
Change in skin Firmness and Elasticity Assessed by Cutometer® Dual MPA 580	Skin firmness and elasticity will be assessed using the Cutometer® Dual MPA 580 at baseline (Week 0), Week 8, Week 16, and Week 24. The Cutometer® Dual MPA 580 is a non-invasive device used to evaluate the biomechanical properties of the skin, including skin firmness and elasticity. Changes in skin biomechanical properties from baseline to Week 24 will be evaluated.	Baseline (Week 0), Week 8, Week 16, and Week 24
Incidence of Treatment-Related Adverse Events	Treatment-related adverse events will be assessed immediately after PLLA injection (Week 0) and at Week 8, Week 16, and Week 24 through participant interviews and clinical examinations. Adverse events including pain, swelling ( edema), bruising (ecchymosis), palpable nodules, granuloma formation, infection, hypersensitivity reactions, and any other treatment-related adverse events will be recorded. Pain will be managed with analgesics as clinically indicated. Early swelling and bruising will be managed with cold compresses, while delayed nodules due to product accumulation may be treated with massage and normal saline injection. Persistent nodules suspected to be granulomas may undergo biopsy for confirmation, followed by intralesional triamcinolone injection if clinically indicated. The outcome measure will be the number and proportion of participants experiencing treatment-related adverse events.	Immediately after PLLA injection (Week 0), Week 8, Week 16, and Week 24

Collaborators and Investigators

• Sponsor: Institute of Dermatology, Thailand

Publications and helpful links

General Publications

• Christen MO. Collagen Stimulators in Body Applications: A Review Focused on Poly-L-Lactic Acid (PLLA). Clin Cosmet Investig Dermatol. 2022 Jun 21;15:997-1019. doi: 10.2147/CCID.S359813. eCollection 2022.
• Tateo A, Siquier-Dameto G, Artzi O, Humzah D, Molina B, Jain R, Lanzarotti A, Laouedj M, Dapis N, Bellia G. Development and Validation of IBSA Photographic Scale for the Assessment of Neck Laxity. Clin Cosmet Investig Dermatol. 2021 Apr 7;14:349-354. doi: 10.2147/CCID.S302860. eCollection 2021.
• Nikolis A, Avelar LE, Enright KM. Evaluation of Cannula Safety in Injection of Poly-L-Lactic Acid. Clin Cosmet Investig Dermatol. 2021 Jun 10;14:615-622. doi: 10.2147/CCID.S305479. eCollection 2021.
• Mazzuco R, Hexsel D. Poly-L-lactic acid for neck and chest rejuvenation. Dermatol Surg. 2009 Aug;35(8):1228-37. doi: 10.1111/j.1524-4725.2009.01217.x. Epub 2009 May 12.

Helpful Links

• Standardizing Dimensionless Cutometer Parameters to Determine In Vivo Elasticity of Human Skin

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): August 1, 2026
• Study Completion (Estimated): September 1, 2026

Study Registration Dates

• First Submitted: June 9, 2026
• First Submitted That Met QC Criteria: July 7, 2026
• First Posted (Actual): July 8, 2026

Study Record Updates

• Last Update Posted (Actual): July 8, 2026
• Last Update Submitted That Met QC Criteria: July 7, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Skin laxity; PLLA; Poly-L-Lactic acid; Neck rejuvenation
• Additional Relevant MeSH Terms: Genetic Diseases, Inborn; Connective Tissue Diseases; Skin Diseases; Skin Diseases, Genetic; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Skin and Connective Tissue Diseases; Cutis Laxa; Therapeutics; Drug Administration Routes; Drug Therapy; Injections; poly(lactide); New-Fill
• Other Study ID Numbers: 006/2568

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No