The Effectiveness of a Whitening and Anti-Aging Bilayering Serum and Cream Containing Gamma-Aminobutyric Acid (GABA) 3%, Dimethylaminoethanol (DMAE) 2%, Cysteamine 2.5%, and Bakuchiol 1%
Phase: PHASE2
Conditions: Skin Aging
Sponsor: Hasanuddin University

STUDY PROTOCOL 
 
Title: Title: The Effectiveness of a Whitening and Anti-Aging Bilayering Serum and Cream 
Containing Gamma-Aminobutyric Acid (GABA) 3%, Dimethylaminoethanol (DMAE) 2%, 
Cysteamine 2.5%, and Bakuchiol 1%  
 
NCT Number: NCT ID not yet assigned 
 
Document Date: February 10th, 2025 
 
This study was experimental research with a double blind randomized controlled 
clinical trial design conducted at the Department of Dermatology & Venereology and 
Hasanuddin University Hospital, Makassar City, South Sulawesi, Indonesia, from March to 
August 2025. This study was approved by the Health Research Ethics Committee, Faculty of 
Medicine, Hasanuddin University, Makassar, with number 93/UN4.6.4.5.31/PP36/2025. 
Subject 
 
The total number of subjects was 44, female, aged between 30-50 years, and Fitzpatrick 
skin type III-V. All participants in the study signed an informed consent form. The exclusion 
criteria were pregnancy, breastfeeding, menopause, using hormonal contraception skin, being 
treated with topical and systemic whitening agents for 1 month before the study began, and had 
a history of GABA, DMAE, Bakuchiol, or Cysteamine allergic reaction. 
Study Protocol 
 Baseline melanin index (MI), L-value, and UV spot values were measured using 
Mexameter®, Chromameter®, and Janus-III Facial Analysis System® tools at week 0. In the 
morning (between 05:00–08:00 Central Indonesia Time), one group cleansed their face using 
five drops of facial wash, followed by the application of two drops of serum containing GABA 
3%, DMAE 2%, Bakuchiol 1%, and Cysteamine 2.5% on both palms. The serum was then 
applied evenly over the entire face until fully absorbed and left on for one minute. A cream 
containing the same active ingredients (GABA 3%, DMAE 2%, Bakuchiol 1%, and 
Cysteamine 2.5%) was applied in an amount equivalent to one fingertip unit (FTU) to the whole 
face. In the evening (between 19:00–22:00), after cleansing the face again with five drops of 
facial wash, the same procedure was repeated—application of two drops of the active serum, 
followed by one FTU of the corresponding cream over the entire face. 

In contrast, the other group followed an identical regimen using placebo products. In the 
morning (05:00–08:00 Central Indonesia Time), participants cleansed their face with five drops 
of facial wash, then applied two drops of placebo serum on both palms and spread it evenly 
over the entire face until absorbed, allowing it to rest for one minute. This was followed by the 
application of one FTU of placebo morning cream over the entire face. In the evening (19:00–
22:00), after cleansing with five drops of facial wash, participants applied two drops of placebo 
serum and then one FTU of placebo night cream, following the same procedure as the morning 
routine. The subjects were randomly allocated into two groups: the treatment group (Group A) 
and the control group (Group B). Both participants and investigators were blinded to group 
allocation. 
The Mexameter® MX 18 (Courage Khazaka, Germany) used 16 LEDs to emit light at 
three wavelengths: 568 nm (green), 660 nm (red), and 880 nm (infrared). The melanin index 
(MI), which corresponds to the skin melanin level, and the erythema index (EI) were obtained 
using a computerized examination. The Chromameter® (Konica Minolta, Japan) objectively 
measured skin color by analyzing the reflection of a xenon lamp perpendicular to the probe at 
450 nm, 560 nm, and 600 nm. The resulting parameters were represented by the numbers L, a, 
and b. The L-value parameter represented the brightness of the skin colour (100 for white and 
0 for black). The Janus-III Facial Analysis System® (PIE Inc, South Korea) was a facial 
analysis system that uses a high-resolution camera to objectively assess various skin issues 
such as pigmented spots, wrinkles, skin tone, UV spots, and sebum production. All data were 
analyzed using Statistical Package for Social Sciences (SPSS) version 22.0 (SPSS. Inc) with 
Unpaired Parametric T-Test was used for normally distributed data, while the Mann–Whitney 
test was applied for non-normally distributed data. Results were considered statistically 
significant at p < 0.05. All data results were presented in tables and graphs.