A single center, prospective clinical study evaluated the tolerability and effectiveness of a series of cosmetic retinol peels, in conjunction with a homecare regimen, to improve the appearance of fine lines, wrinkles, skin firmness, and overall complexion brightness on subjects with mild to moderate photodamage across a range of peel candidates, including those with moderate acne, hyperpigmentation or melasma, and skin of color.
Formulation Strategy
An anhydrous peel formulation was developed to deliver 3% retinol to the skin as the primary antiaging benefit ingredient.
Retinol, a precursor to retinoic acid with better tolerance, increases epidermal thickness and reduces MMP activity while enhancing collagen.5-7 This peel contains triethyl citrate and the amino acid derivative acetyl tyrosinamide to collectively increase collagen and hyaluronic acid shown to plump and firm skin.9-11 The formula also contains the soothing and calming agent bisabolol, a botanical derived from chamomile. Vitamin E acetate functions both as a skin protectant and provides antioxidant protection for retinol in the formulation. Additionally, the anhydrous vehicle solution contains a photostabilizer and is packaged in amber unit dose vials (2 mL) to preserve the stability of the retinol. The formulation is preservative free, fragrance free, oil free, and dye free (Table 1).
Formulation Strategy
An anhydrous peel formulation was developed to deliver 3% retinol to the skin as the primary antiaging benefit ingredient.
Retinol, a precursor to retinoic acid with better tolerance, increases epidermal thickness and reduces MMP activity while enhancing collagen.5-7 This peel contains triethyl citrate and the amino acid derivative acetyl tyrosinamide to collectively increase collagen and hyaluronic acid shown to plump and firm skin.9-11 The formula also contains the soothing and calming agent bisabolol, a botanical derived from chamomile. Vitamin E acetate functions both as a skin protectant and provides antioxidant protection for retinol in the formulation. Additionally, the anhydrous vehicle solution contains a photostabilizer and is packaged in amber unit dose vials (2 mL) to preserve the stability of the retinol. The formulation is preservative free, fragrance free, oil free, and dye free (Table 1).
METHODS
The study protocol was approved by an institutional review board (IRB) and informed consent was obtained prior to enrollment. The study consisted of a group of 14 subjects with photodamaged skin (Photodamage group), including five subjects with acne (Acne subgroup). An additional 10 subjects with Fitzpatrick skin types IV-VI (Skin of Color group, n=5) or mild to moderate melasma or hyperpigmentation, as noted with a grade of 3-6 on the 0-9 modified Griffith’s scale (Melasma group, n=5), were also included. The Photodamage group, Acne subgroup, Skin of Color group, and Melasma group consisted of females ages 18-65 years with mild to moderate photodamage on the face (fine lines, wrinkles, and/or mottled pigmentation with a grade of 3-6 on the 0-9 modified Griffith’s scale). Females in the Acne subgroup had moderate global facial acne (grade 3 on a 0-4 scale). To be eligible for inclusion, subjects were required to be free of disease or history of disease and without medication usage that could interfere with the study or expose study subjects to unacceptable risks. Subjects also could not have used prescription topical retinoids within 8 weeks, or systemic retinoids within 6 months. Furthermore, they could not have had facial chemical peels, or other resurfacing procedures within 6 months of study start, and could not have used topical cosmetic hydroxyacids, retinol, or other high-strength physician-dispensed antiaging formulations on their face within 4 weeks of study enrollment. Subjects who had regularly used any topical prescription or over the counter facial medications or cleansers on their face within 2 weeks of study enrollment were excluded. Subjects could not be pregnant or breastfeeding, planning to become pregnant during the course of the study, or have known allergies or sensitivities to topical skin products. Subjects who were required to spend excessive time in the sun were not eligible for the study. Subjects received the 3% retinol peel at the study physician’s office approximately every 6 weeks. Each peel procedure was identical for all treatment groups and utilized a pre-peel cleanser followed by application of the retinol peel. Subjects were instructed to remove the peel at home after at least 8 hours with a 4% polyhydroxy acid (PHA) facial cleanser. The study dermatologist monitored the skin’s reaction to the peel for 10 minutes in the office. After washing the peel off the skin and for up to one week after, subjects used the 4% PHA facial cleanser twice daily, a 12% Bionic/PHA post-peel face cream or 10% Bionic post-peel face serum, with sunscreen (10% Bionic/PHA day cream SPF 23, or 4% Bionic/PHA physical sunscreen SPF 50). Thereafter, subjects followed a homecare regimen consisting of the 4% PHA facial cleanser (morning and night), 10% Bionic/PHA day cream SPF 23 (morning), 4% Bionic/PHA physical sunscreen SPF 50 (as desired), and a 10% PHA night cream (night). Test materials were packaged in blinded containers. The Photodamage group and Acne subgroup received a total of four peels,
