Effects of topical ectoine on skin responses to different laser treatments

INTERVENTION: Participants underwent controlled laser procedures at predefined anatomical sites using a randomized within‐participant design. Different areas within the same participant were assigned to topical ectoine‐containing formulations or a corresponding vehicle formulation without ectoine. In the neck study component, one side of the neck was preconditioned with a topical formulation containing 7% ectoine applied twice daily before ablative Er:YAG laser treatment, while the contralateral side received the corresponding vehicle formulation. Skin biophysical parameters were assessed at: T0: before initiation of preconditioning (baseline) T1: after completion of 7 or 14 days of preconditioning, immediately before Er: YAG treatment T2: immediately after Er:YAG treatment T3: 24 h after Er:YAG treatment T4: 7 days after Er:YAG treatment In the facial study component, both sides of the face underwent identical vascular Nd:YAG laser treatment. Following treatment, one side received a topical formulation containing 7% ectoine and the contralateral side received the corresponding vehicle formulation. The assigned formulations were applied twice daily throughout the study period. Participants underwent four laser treatment sessions at 7‐day intervals. Skin biophysical parameters were assessed at: T0: before the first Nd:YAG treatment T1: before the third treatment, after the first two therapeutic sessions T2: 7 days after the fourth and final treatment In the décolletage study component, predefined test fields were exposed to different laser modalities and compared across topical formulations containing different ectoine concentrations (1%, 5%, and 7%) and vehicle control. The protocol also evaluated different timing strategies, including ectoine preconditioning before laser exposure and post‐treatment application. Skin biophysical parameters were assessed at: T0: before the start of the 7‐day preconditioning period T1: immediately after laser exposure T2: 24 hours after exposure T3: 14 days after exposure Treatment allocation to anatomical sides or predefined test areas was randomized according to the respective study component. Cutaneous response and recovery were evaluated using standardized instrumental and imaging assessments at predefined time points. CONDITION: Cutaneous response to laser exposure and subsequent skin recovery, including skin barrier function, hydration, erythema, pigmentation, and skin structural parameters, as well as facial erythema treated with vascular laser therapy ; Skin and Connective Tissue Diseases PRIMARY OUTCOME: Cutaneous response and recovery following laser exposure measured using instrumental assessment of skin barrier function and cutaneous response using transepidermal water loss (TEWL), corneometry, erythema index, USG and standardized skin imaging at baseline and predefined post‐intervention follow‐up timepoints according to each study component (see Interventions field for the full list) INCLUSION CRITERIA: 1. Adults aged 29–65 years 2. Male and female participants 3. Fitzpatrick skin phototype II 4. Healthy skin in the anatomical areas selected for experimental laser exposure, where applicable 5. Presence of facial erythema suitable for vascular Nd:YAG laser treatment for participants included in the facial study component 6. Eligibility to undergo the laser procedures specified in the respective study component 7. Ability and willingness to comply with the study procedures, topical product application regimen, and scheduled follow‐up assessments 8. Provision of written informed consent