This prospective, single-center, split-area exploratory evaluation compared the effects of a high-concentration hyaluronic acid skinbooster (Hyamira 40 Booster®; NyumaPharma) with another hyaluronic acid skinbooster (Profhilo Structura® (IBSA Farmaceutici Italia Srl)) [32] on the skin quality of the face, neck, décolleté, and hands.

Profhilo Structura® was selected as the comparator because it is an established hyaluronic acid-based injectable used in aesthetic practice for skin-quality improvement. Its use as a comparator allowed Hyamira 40 Booster® to be evaluated alongside a clinically familiar HA-based product within the same broad treatment category.

The evaluation was conducted at PHP Aesthetic-Wellness in the United Kingdom. Participants were followed for approximately 2 - 3 months and completed four scheduled visits.

No formal sample size calculation was performed; the study was designed as an exploratory pilot evaluation.

Adult volunteers seeking improvement in skin quality in one or more of the targeted anatomical regions were eligible. The evaluation excluded women who were pregnant, breastfeeding, or planning to become pregnant. Women who suspected pregnancy or intended to conceive during the study period were likewise excluded.

At the initial screening/treatment visit (Day −1 to Day 0), written informed consent was obtained before any study-related procedures. Demographic data (age and gender), medical and medication history, including prescription medications, over-the-counter treatments, and dietary or herbal supplements, were recorded. A physical examination, including height and weight, was performed. Eligibility was confirmed by the investigator in accordance with the inclusion and exclusion criteria.

A split-area design was employed for all treated anatomical regions. For each region, Hyamira 40 Booster was administered on one side and Profhilo Structura on the contralateral side. Hyamira 40 Booster contains 40 mg/mL of hyaluronic acid.

Participants were blinded to the side allocation, while the investigator was aware of the assignment, resulting in a single-blinded design.

Side assignment was not randomized. Allocation of Hyamira 40 Booster and the comparator to the left or right side was determined by the investigator and remained consistent across treatment sessions for each participant.

Participants could receive treatment to the face, neck, décolleté, and hands based on individual presentation and clinical judgment. At each treatment session, 1 mL of each product was administered per side for each treated area (i.e., 1 mL of Hyamira 40 Booster on one side and 1 mL of the comparator on the contralateral side), distributed across multiple injection points. All injections were performed in the superficial subdermal plane using a 25 G/60 mm cannula (Magic Needle®, Needle Concept). Treatments were delivered under standard clinical conditions for superficial subdermal injection.

The study comprised four visits. Visit 1 (Day −1 to Day 0) included screening assessments followed by the first treatment session. Visit 2 (Day 15 ± 3 days) consisted of the second treatment. Visit 3 (Day 30 ± 3 days) served as a follow-up visit and included a repeat treatment session in accordance with the protocol. Visit 4 (Day 45 ± 3 days) was a follow-up evaluation assessing the progression of treatment outcomes.

Clinical outcomes were assessed using a patient-reported Global Aesthetic Improvement Scale (GAIS, higher scores indicate greater perceived improvement) and a patient satisfaction questionnaire. The GAIS measured the patient’s perception of changes for each treated side across several parameters of skin quality, including skin radiance, skin elasticity, skin hydration, skin smoothness, and overall skin quality. Patients completed this evaluation independently at the designated follow-up visits.

At Visit 1, the GAIS assessment was completed after the initial treatment session and therefore reflected early post-treatment perception rather than a true pre-treatment baseline. At subsequent visits, GAIS and satisfaction assessments were completed before any additional treatment was administered during that visit.

Participants also completed a structured satisfaction questionnaire that captured their overall impressions of treatment efficacy and tolerance, as well as their side-by-side preference between the two injected products. These patient-reported outcomes were used to characterize subjective aesthetic improvements throughout the evaluation period.

The GAIS was scored on a seven-point ordinal scale ranging from −3 (Very Much Worse) to +3 (Very Much Improved), with 0 indicating No Change and higher scores indicating greater perceived improvement. The 16-item satisfaction questionnaire was developed specifically for this evaluation and was not a previously validated instrument. Responses were summarized descriptively, and items requiring direct side-by-side comparison were reported as the proportion of participants selecting each response category.

Participants agreed not to undergo any additional aesthetic procedures involving the face, neck, décolleté, or hands for the duration of their participation. Makeup was not permitted on visit days or for twelve hours after each injection. Participants were instructed to avoid sunlight or ultraviolet exposure throughout the evaluation period and to refrain from exposure to extreme temperatures, including intense cold, saunas, and hammam, for two weeks following each injection. Touch-ups or re-injections outside the protocol-defined treatment sessions were not allowed. All adverse events and any changes in medication were to be reported promptly to the investigator.

Descriptive statistics were used to summarize all outcomes. Paired comparisons from baseline were performed using a two-tailed paired Student’s t-test and are reported as exploratory, unadjusted analyses. Although GAIS scores are ordinal, they were treated as continuous variables for the purpose of this exploratory analysis. All p-values were considered exploratory and were not adjusted for multiple comparisons.

Skin radiance increased progressively from baseline in all treated regions (Figure 1). For the face, mean GAIS radiance scores improved from 0.2 at Visit 1 to 1.0 at Visit 2 (p = 0.0161), 1.8 at Visit 3 (p = 0.00284), and 2.2 at Visit 4 (p = 0.00320).

For the neck, radiance increased from 0 at Visit 1 to 1.0 at Visit 2, 1.75 at Visit 3 (p = 0.00599), and 2.0 at Visit 4.

Changes in skin radiance scores measured on the face, neck, décolleté, and hands at the different study visits (V1 - V4). Data are presented as mean ± standard deviation for the left and right sides. Asterisks indicate within-side statistically significant differences compared with baseline (*p < 0.05; **p < 0.01).

Figure 1. Skin radiance assessment over time.

For the décolleté, scores rose from 0 at baseline to 1.0 at Visit 2 and 1.67 at Visit 3 (p = 0.03775), reaching 2.0 at Visit 4.

For the hands, radiance increased from 0.25 at Visit 1 to 1.5 at Visit 2 (p = 0.07960), 2.0 at Visit 3 (p = 0.00599), and 2.5 at Visit 4 (p = 0.01822).

Across all regions, the left and right sides showed similar mean scores at every visit, with no consistent differences observed between Hyamira 40 Booster and the comparator. The p-values provided reflect within-side improvement over time, and several timepoints reached statistical significance (p < 0.05).

Skin elasticity improved progressively from baseline across all anatomical regions (Figure 2). For the face, mean elasticity increased from 0 at Visit 1 to 1.0 at Visit 2 and 1.4 at Visit 3 (p = 0.00464), reaching 2.0 at Visit 4.

In the neck, scores increased from 0 at Visit 1 to 1.0 at Visit 2 and 1.25 at Visit 3 (p = 0.01539), with further improvement to 2.0 at Visit 4.

For the décolleté, elasticity progressed from 0 at baseline to 1.0 at Visit 2 and remained at 1.0 at Visit 3 (p = 0.03775), increasing to 2.0 at Visit 4.

For the hands, scores rose from 0 at Visit 1 to 1.0 at Visit 2 and 1.5 at Visit 3 (p = 0.01385), with further improvement to 2.25 at Visit 4 (p = 0.00290).

Across all regions, the left and right sides exhibited similar mean scores, with no consistent differences observed between sides.

Evolution of skin elasticity scores on the face, neck, décolleté, and hands from baseline (V1) to the final visit (V4). Values represent mean ± standard deviation for left and right sides. Asterisks indicate within-side statistically significant differences compared with baseline (*p < 0.05; **p < 0.01).

Figure 2. Skin elasticity assessment over time.

Skin hydration improved consistently across all anatomical regions following treatment (Figure 3). For the face, mean hydration scores increased from 0.6 at Visit 1 to 1.4 at Visit 2 (p = 0.01613), 2.0 at Visit 3 (p = 0.00464), and 2.4 at Visit 4 (p = 0.00858).

In the neck, hydration increased from 0 at baseline to 1.25 at Visit 2 (p = 0.01539), reaching 2.0 at Visit 3 and 2.5 at Visit 4 (p = 0.00324).

For the décolleté, scores progressed from 0 at Visit 1 to 1.33 at Visit 2 (p = 0.05719), 2.0 at Visit 3, and 2.67 at Visit 4 (p = 0.01527).

For the hands, hydration increased from 0.5 (left) and 0.75 (right) at Visit 1 to 1.5 at Visit 2 (right-side p = 0.05767), then to 2.0 at Visit 3 (p = 0.01385 for left; p = 0.01539 for right), and 2.5 at Visit 4 (p = 0.04052 for left; p = 0.03535 for right).

Across all four regions, mean hydration values were equal on both treated sides at nearly all visits, indicating similar hydration trends.

Skin smoothness improved progressively across all anatomical regions following treatment (Figure 4). For the face, mean smoothness increased from 0 at Visit 1 to 0.8 at Visit 2 (p = 0.01613), 1.4 at Visit 3 (p = 0.00464), and 2.0 at Visit 4.

Skin hydration scores assessed on the face, neck, décolleté, and hands at each visit (V1 - V4). Results are expressed as mean ± standard deviation for left and right sides. Asterisks indicate within-side statistically significant differences compared with baseline (*p < 0.05; **p < 0.01).

Figure 3. Skin hydration assessment over time.

Progression of skin smoothness scores on the face, neck, décolleté, and hands throughout the study visits (V1 - V4). Data are shown as mean ± standard deviation for left and right sides. Significant within-side differences versus baseline are marked (*p < 0.05; **p < 0.01).

Figure 4. Skin smoothness assessment over time.

In the neck, smoothness increased from 0 at baseline to 0.75 at Visit 2 (p = 0.05767), 1.25 at Visit 3 (p = 0.01539), and reached 2.0 at Visit 4.

For the décolleté, scores rose from 0 at Visit 1 to 0.67 at Visit 2 (p = 0.18350), then to 1.0 at Visit 3, and 2.0 at Visit 4.

For the hands, smoothness improved from 0.25 at Visit 1 to 0.75 at Visit 2 (p = 0.18169), 1.25 at Visit 3, and 2.25 at Visit 4 (p = 0.01628).

Across all regions, the left and right sides demonstrated equivalent mean values at every time point, showing similar trends in skin smoothness on both treated sides.

Overall skin quality improved consistently across all anatomical regions during the evaluation period (Figure 5). For the face, mean GAIS scores increased from 0.4 at Visit 1 to 1.2 at Visit 2 (p = 0.01613), 1.6 at Visit 3 (p = 0.00388), and 2.2 at Visit 4 (p = 0.00858).

In the neck, overall quality improved from 0.25 at Visit 1 to 1.0 at Visit 2 (p = 0.05767), 1.5 at Visit 3 (p = 0.01539), and 2.0 at Visit 4 (p = 0.00599).

For the décolleté, overall skin quality increased from 0.33 at baseline to 1.0 at Visit 2 (p = 0.18350), 1.33 at Visit 3, and 2.0 at Visit 4 (p = 0.03775).

For the hands, scores progressed from 0.5 at Visit 1 to 1.25 at Visit 2 (p = 0.05767), 2.0 at Visit 3 (p = 0.01385), and 2.75 at Visit 4 (p = 0.01822).

Changes in global skin quality scores evaluated on the face, neck, décolleté, and hands from V1 to V4. Results are presented as mean ± standard deviation for left and right sides. Asterisks indicate within-side statistically significant improvements compared with baseline (*p < 0.05; **p < 0.01; ****p < 0.0001).

Figure 5. Overall skin quality improvement over time.

Across all regions, the left and right sides demonstrated similar mean scores at all visits, showing similar trends in overall skin quality on both treated sides.

A structured 16-item patient satisfaction questionnaire was administered at each visit beginning at Visit 2 to assess subjective treatment experience and perceived aesthetic improvements for each treated side. Patient-reported satisfaction was consistently high throughout the study and showed no appreciable differences between the two treated sides. For all 16 questionnaire items, participants selected the same response for both the Hyamira-treated and comparator-treated sides. Agreement ratings predominantly fell within the “Totally agree” or “Somewhat agree” categories for all evaluated parameters, including injection comfort, skin tolerance, overall satisfaction, rested appearance, complexion freshness, wrinkle reduction, skin tone, fatigue, firmness, hydration, smoothness, texture, plumpness, brightness, and overall skin quality. For all questions requiring side-by-side comparison, patients uniformly selected “Equal”, indicating no subjective preference for either product. All participants reported that the three-session protocol was not inconvenient.

Treatment was well tolerated overall. Reported injection-site reactions were mild and transient and resolved without intervention. No serious adverse events, nodules, persistent induration, or delayed complications were reported. No participant discontinued treatment or follow-up because of tolerability concerns.