We present here a new cosmetic formula system containing 3% ascorbic acid based on an optimized oil-in-water (O/W) emulsion. This formulation demonstrated a good long-term stability of the active ingredient and also of the emulsion itself. It could be deduced from in vitro release studies that this O/W emulsion enabled a better release of the hydrophilic active agent than an alternative W/O emulsion. By measuring the ultraweak photon emission, which is a well-established parameter for the oxidative stress in the skin, the high in vivo antioxidant capacity of 3% ascorbic acid was demonstrated after 1 week of product application. This placebo-controlled study also proved that ascorbic acid in an O/W cream reduced oxidative stress in human skin significantly better than the derivative sodium ascorbyl-2-phosphate, a more stable vitamin C replacement commonly used in cosmetic formulations. With increasing age, the number of papillae in the epidermal-dermal junction zone in human skin are reduced. This implies a possible consequence of reduced mechanical resistance of the skin and impaired supply of the epidermis with nutrients. In a 1-month placebo-controlled study on 25 human volunteers, a significant increase in the number of dermal papillae after application of the 3% ascorbic acid cream was demonstrated, using a confocal laser scanning microscope. Fine lines and wrinkles are a characteristic sign of aged and especially photo-aged skin. Application of 3% ascorbic acid in a 12-week placebo-controlled usage study indicated a significant reduction of facial wrinkles. Altogether, 3% ascorbic acid in a cosmetic O/W emulsion has been shown to be appropriately stable and to enable a good release of the active agent in vitro as a precondition for a high efficacy in vivo. Application in vivo resulted in a significant reduction of oxidative stress in the skin, an improvement of the epidermal-dermal microstructure and a reduction of fine lines and wrinkles in aged skin. These results were received within a relatively short period of time of product application.

Background/Aims: Dry, itchy and inflamed scalp conditions are common and often associated with diseases such as atopic dermatitis or psoriasis. To improve these symptoms, we investigated the efficacy of a new tonic containing the active ingredients urea, lactate, polidocanol, and Glycyrrhiza inflata root extract, containing licochalcone A. Study Design/Methods: 30 subjects with dry and itchy scalp conditions underwent a randomized half-head study for 4 weeks, applying the leave-on tonic three times a week on one side of the scalp. Tonic effects on skin hydration, itching, lipids, microinflammation, and substantivity of tonic compounds were determined using corneometry, middle-infrared spectroscopy, direct analysis in real-time mass spectrometry, and enzyme-linked immunosorbent assay. Volunteers performed a self-assessment; changes in scalp condition were documented by in vivo microscopy. Results: After tonic treatment, scalp moisture was significantly increased, whereas scalp itching and tautness were significantly reduced. Results also demonstrated a high substantivity of urea and lactate on the scalp, an increase in triglyceride, and a decrease in free fatty acid levels. The amount of total lipids was unchanged. Analyses of scalp wash-ups verified a significant reduction in important pro-inflammatory markers. Conclusion: Due to the actives urea, lactate, polidocanol, and the anti-inflammatory licochalcone A, the new scalp tonic exhibited excellent performance in alleviating scalp dryness, itching, microinflammation, and in normalizing disturbances of scalp lipids.

Prevention of the flares is a main goal in the long-term treatment of atopic dermatitis (AD). Therefore we investigated the efficacy of a water-in-oil emollient, containing licochalcone A, omega-6-fatty acids, ceramide 3 and glycerol, for prevention of the flares in adults with mild to moderately severe AD, treated with topical steroids, that led to clearing of the inflammatory lesions and had been discontinued prior to inclusion. The study was a 12-week, double-blind, randomized, vehicle-controlled, left-right comparison test with the number of relapses, defined as re-occurrence of erythema for at least 3 consecutive days, considered the primary outcome. Compared with the vehicle, the active formulation significantly reduced the number of relapses and maintained the barrier homeostasis of the respective arm. To the best of knowledge, this is the first study to show prevention of the AD flares by the use of stand-alone emollient treatment, based on comparison with the corresponding vehicle while excluding concomitant/rescue medications.

OBJECTIVE: Tyrosinase is the rate-limiting enzyme in melanogenesis. Thiamidol is the most potent inhibitor of human tyrosinase out of 50 000 tested compounds. In clinical studies, it was shown to improve facial hyperpigmentation, post-inflammatory hyperpigmentation and age spots significantly. To identify the optimal number of daily Thiamidol applications, we conducted a split-face study comparing the efficacy and tolerability of four-times with two-times daily application. Subsequently, we evaluated the efficacy and tolerability of a typical face care regimen containing Thiamidol in a real-world study. METHODS: The split-face study was double-blind, randomized, controlled, including two Thiamidol containing products (serum and day care SPF 30). The serum was applied twice daily on one half of the face and the day care SPF30 twice-daily on the whole face. The real-world study was open-label, observational, including three Thiamidol containing products (day care SPF 30 in the morning, serum and night care in the evening). In both studies, subjects with mild-to-moderate facial hyperpigmentation applied the products over 12 weeks. Assessments included clinical and subjective grading of hyperpigmentation, skin condition, hemi-/modified MASI, chromameter and clinical photography. RESULTS: In the split-face study (n = 34), hyperpigmentation, skin roughness and hMASI improved all significantly (P < 0.001) versus baseline, with first visible results after two weeks of twice-daily application. The four-times daily application led to significant improvement versus the two-times daily application. In the real-world study (n = 83), all evaluated parameters, including skin condition and chromametry (n = 30), improved significantly (P < 0.001) in comparison with baseline and the corresponding preceding visits. The subjects judged the cosmetic properties of the products positively. In both studies, the products were well tolerated. CONCLUSION: Four-times daily Thiamidol improves facial hyperpigmentation significantly more than two-times daily and is well tolerated by the subjects. The real-world study with a typical face care regimen containing Thiamidol shows improvement of facial hyperpigmentation and confirms tolerability. Furthermore, the data provide evidence for the suitability of this three-product Thiamidol regimen for day-today life.

In 40 volunteers the efficacy of three lotions with 10% hamamelis distillates from different suppliers, two vehicles, dimethindene maleate 0.1% gel, hydrocortisone 1% cream and hydrocortisone 0.25% lotion were investigated in a modified UV erythema test with three UV dosages (1.2, 1.4 and 1.7 MED). The test preparations were applied occlusively over a 48-hour period following irradiation. Chromametric measurement of redness and visual assessment were performed 24, 48 and 72 h after induction of erythema. The hydrocortisone formulations were most effective in erythema suppression. An anti- inflammatory effect was noted for all three hamamelis lotions as well as for the vehicles. A significantly greater suppression of erythema than seen with the vehicles was noted for one of the hamamelis lotions at 1.4 MED. The efficacy of the antihistamine dimethindene maleate did not surpass the hamamelis lotions or the vehicles. Even though the differences between the hamamelis lotions were slight, it was possible to make an objective selection of the best hamamelis distillate for aftersun purposes.