A randomized split-face double-blind control trial of 2%Pine Bark Extract topical cream versus placebo on the treatment of melasma in THAIS

Abstract

Introduction: Melasma is a commonly acquired disorder of facial hyperpigmentation that is primarily a concern for people with a darker skin type (Fitzpatrick’s skin type III-V), especially Asian women, including Thai women. Pine Bark Extract (PBE) has strong antioxidant, anti-inflammatory, anti-tyrosinase properties, as well as UV protection, for the treatment of melasma.

Objectives: To compare the clinical effectiveness of a 2% Pine Bark Extract topical cream and a placebo cream in melasma patients.

Methods: Prospective, split-face, double-blind, randomized, controlled clinical trial studies in 18 Thai subjects who are 30-60 years old with Fitzpatrick’s skin type III-V were used to compare the clinical effectiveness of 2% PBE topical cream and a placebo cream to treat melasma. The result of all subjects’ Repeated Open Application Tests were negative. Subjects were randomly assigned to use the PBE cream on one side of their face and the placebo cream on the other side of their face for eight weeks. Subjects also had to apply sunscreen SPF 50 PA+++ on their whole face. They were evaluated at the 0^th, 4^th, and 8^th weeks concerning the mean melanin index (MMI) on their cheek and half of their face, as well as the modified MASI (mMASI) score, which is evaluated by three dermatologists, brown spots, UV spots, subject’s satisfaction, and adverse effects.

Result: All 17 subjects are completely followed up 3 months, with only one subject did not participate in the follow-up evaluations. Efficacy results demonstrated a statistically significant reduction in MMI on the cheek of the PBE group was significantly less than that of the placebo group (p=0.009) at Week8. And the total MMI on half of the face in the PBE group was significantly less than that of the placebo group (p=0.005) at Week 8. There was no statistically significant reduction in the numbers of brown spots, UV spots, or mMASI score between the groups. The evaluation of subjects’ satisfaction with the PBE cream at the 4^th week was significantly greater than that of the placebo group (p=0.011). Adverse effects at the 8^th week including scaling in 5 subjects of the PBE group, while there were 4 subjects that reported scaling and 1 subject that reported acne as an adverse effect in the placebo group.

Conclusion: The 2% Pine Bark Extract topical cream has higher ability to reduce darkness caused by melasma than the placebo, with significant difference at the 8^th week and a higher satisfaction score at the 4^th week.