An interventional study of Chemical skin biostimulation with ammonium trichloroacetate and homocysteic acid in Skin Aging and Hyperpigmentation, sponsored by Medical University of Silesia. Completed at 1 site in Poland. Open to female participants aged 39 Years to 69 Years. Per ClinicalTrials.gov, last updated 2026-07-23.
Sponsored by Medical University of Silesia · Not applicable, Interventional, and Treatment
This study evaluated whether a chemical skin biostimulator containing ammonium trichloroacetate, homocysteic acid, phytic acid and citric acid can improve signs of photoaged skin in women with mature skin. Twenty-five women received four treatment sessions two weeks apart, followed by a home-care skincare regimen. Skin firmness, wrinkles, skin texture, hydration, sebum production and, in participants with hyperpigmentation, skin tone uniformity were measured before treatment and at 2 and 12 weeks after the treatment series to determine whether the biostimulator produces lasting improvement in photoaged skin without the downtime associated with traditional chemical peels.
This was a single-arm, prospective, open-label study conducted at a single academic centre to assess the clinical and instrumental effects of a chemical skin biostimulator (PRX plus, WiQO, Trieste, Italy) on facial photoaging. The intervention combines ammonium trichloroacetate (ATCA), a controlled-penetration TCA derivative intended to stimulate dermal fibroblast activity and collagen remodelling, with homocysteic acid (HoA), a novel antioxidant and NMDA-receptor-modulating molecule proposed to influence keratinocyte differentiation, epidermal barrier function and melanocyte activity, together with low concentrations of phytic and citric acids providing mild keratolytic and antioxidant effects. Treatment consisted of a standardised four-session protocol (three product layers per session) applied to defined facial regions of interest, combined with a daytime regenerating cream, a nighttime glycolic-acid-containing fluid, and, in participants with hyperpigmentation, a twice-daily lightening serum. Outcomes were assessed instrumentally using Cutometer (skin viscoelasticity), Antera 3D (wrinkle volume and surface texture), corneometry and sebumetry (hydration and sebum), and grey-level co-occurrence matrix (GLCM) analysis of standardised cross-polarised photographs (skin tone homogeneity in the hyperpigmented subgroup), at baseline, 2 weeks after the final session, and 12 weeks after completion of the treatment series, to characterise both the immediate and sustained effects of the intervention.
127 studies on the registry are indexed under Hyperpigmentation; 28 are open to participants now.
This study's enrollment of 25 is below the median of 32 across 113 interventional studies indexed under Hyperpigmentation.
Browse Hyperpigmentation studies →Medical University of Silesia is the lead sponsor of 115 studies on the registry; 26 are open to participants now.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Women with clinical signs of facial photoaging received four sessions, at 14-day intervals, of a topical chemical skin biostimulator containing ammonium trichloroacetate (ATCA), homocysteic acid (HoA), phytic acid and citric acid (PRX plus, WiQO), followed by a standardised home-care regimen consisting of a regenerating cream (morning), a glycolic-acid-containing fluid (evening), and, in participants with hyperpigmentation, a lightening serum applied twice daily to affected areas.
Procedure: Chemical skin biostimulation with ammonium trichloroacetate and homocysteic acid
A four-session chemical skin biostimulation procedure using a topical formulation containing ammonium trichloroacetate (ATCA), homocysteic acid (HoA), phytic acid and citric acid (PRX plus, WiQO, Trieste, Italy). At each session, three product layers were applied to predefined facial areas (forehead, nose, cheeks, chin, upper lip) with massage until absorption, followed by cold-water rinse. Sessions were repeated at 14-day intervals. Participants additionally followed a standardised home-care regimen: a regenerating shea-butter cream each morning, a glycolic-acid-containing fluid each evening, and, for participants with hyperpigmentation, a lightening serum applied twice daily to affected areas, together with daily broad-spectrum sunscreen (SPF 50+).
Also known as: PRX plus
Change From Baseline in Skin Viscoelasticity (Cutometer R2, R5, R7)
Skin viscoelasticity assessed by Cutometer, reported as gross elasticity (R2), net elasticity (R5) and biological elasticity (R7); each is a dimensionless ratio ranging from 0 to 1, with higher values indicating greater skin elasticity.
Time frame: Baseline, 2 weeks, and 12 weeks after the treatment series
Change From Baseline in Wrinkle Volume (Antera 3D)
Wrinkle volume at the nasolabial folds, glabellar lines, forehead lines, and crow's feet, measured in mm³ by Antera 3D three-dimensional imaging.
Time frame: Baseline, 2 weeks, and 12 weeks after the treatment series
Change From Baseline in Skin Texture Score (Antera 3D)
A proprietary continuous index from the Antera 3D imaging software (Miravex) reflecting skin surface irregularity, with no manufacturer-published fixed range; observed values in this study ranged from approximately 20 to 55, with higher values indicating rougher skin.
Time frame: Baseline, 2 weeks, and 12 weeks after the treatment series
Change From Baseline in Skin Roughness (Antera 3D, Ra)
Arithmetic roughness (Ra), measured in micrometres (µm) by Antera 3D.
Time frame: Baseline, 2 weeks, and 12 weeks after the treatment series
Change From Baseline in Maximum Wrinkle Height (Antera 3D)
Maximum surface height of wrinkles, measured in millimetres (mm) by Antera 3D.
Time frame: Baseline, 2 weeks, and 12 weeks after the treatment series
Change From Baseline in Skin Hydration
Skin hydration measured by corneometry (arbitrary corneometer units).
Time frame: Baseline, 2 weeks, and 12 weeks after the treatment series
Change From Baseline in Sebum Secretion
Sebum secretion measured by sebumetry.
Time frame: Baseline, 2 weeks, and 12 weeks after the treatment series
Change From Baseline in Skin Tone Contrast (GLCM) in Participants With Hyperpigmentation
Grey-level co-occurrence matrix (GLCM) contrast index in the hyperpigmented subgroup (n=14), assessed from standardised cross-polarised photographs.
Time frame: Baseline, 2 weeks, and 12 weeks after the treatment series
Change From Baseline in Skin Tone Homogeneity (GLCM) in Participants With Hyperpigmentation
Grey-level co-occurrence matrix (GLCM) homogeneity index (range 0-1; higher values indicate greater uniformity) in the hyperpigmented subgroup (n=14).
Time frame: Baseline, 2 weeks, and 12 weeks after the treatment series
Change in Self-Assessed Facial Appearance, Neck Appearance, Wrinkle Depth, and Skin Firmness
Participants' perceived change in facial appearance, neck appearance, wrinkle depth, and skin firmness after the treatment series, each rated on a Likert scale from -5 (marked worsening) to +5 (marked improvement), with 0 indicating no change.
Time frame: Immediately after the fourth treatment session (each session is a single-day clinic visit; the four sessions were administered at 14-day intervals), compared with baseline
Satisfaction With Wrinkle-Reduction and Firming Effects
Participants' satisfaction with the wrinkle-reduction effect and with the firming effect of the treatment, each rated on a scale from 0 (not satisfied at all) to 10 (extremely satisfied).
Time frame: Immediately after the fourth treatment session (each session is a single-day clinic visit; the four sessions were administered at 14-day intervals)
Proportion of Participants Satisfied With Facial and Neck Appearance
Percentage of participants reporting satisfaction with the appearance of their face and neck, assessed before treatment and after the treatment series.
Time frame: Baseline and immediately after the fourth treatment session (each session is a single-day clinic visit; the four sessions were administered at 14-day intervals)
Percentage Retention of Maximal Improvement in Wrinkle Volume and Skin Texture at 12 Weeks
Persistence of the treatment effect, calculated as the percentage of the maximal improvement (observed at 2 weeks) that was retained at 12 weeks, for wrinkle volume and skin texture/roughness parameters measured by Antera 3D.
Time frame: 2 weeks and 12 weeks after the treatment series
Incidence of Local Skin Reactions and Adverse Events
Clinical monitoring for adverse events and local skin reactions associated with the procedure.
Time frame: Throughout the treatment series and follow-up period, up to 12 weeks after the last session
Plan to share: Yes — The individual participant data underlying the results reported in this article are included in the article and its supplementary materials. Further inquiries can be directed to the corresponding author.
Supporting information: Study protocol
Time frame: Available upon reasonable request from the corresponding author, beginning from the date of publication, with no specified end date.
Access criteria: Data will be made available to qualified researchers who submit a reasonable request to the corresponding author (Anna Deda, adeda@sum.edu.pl), for the purpose of methodologically sound reanalysis, subject to authors' approval.
This study is completed, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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