Assessment of the Effect of Rehmannia glutinosa Leaf Extract in Maintaining Skin Health: A Proof-of-Concept, Double-Blind, Randomized, Placebo-Controlled Clinical Trial

Abstract

Purpose

A double-blind, placebo-controlled, randomized, proof-of-concept trial aimed to evaluate the efficacy and safety of Verbasnol^TM [Rehmannia glutinosa Libosch leaf-based extract (RGLE)] in females, with moderate to severe acne vulgaris.

Participants and Methods

Twenty-two females aged 18 to 35 years having moderate to severe acne with Global Acne Grading System (GAGS) scores of 19 to 38 were included in the study and were randomized in a 1:1 ratio to receive either one capsule (100 mg/day) of RGLE or placebo orally after breakfast for 56 days. The primary outcome was a change in acne severity measured by the GAGS compared to the placebo on day 56. The secondary outcomes were changes in the number of inflammatory acne lesions, facial sebum secretion, quality of life, local pain and itching, skin wrinkle severity, and other skin characteristics, including radiance, luminosity, smoothness, texture, firmness, and hydration. Additionally, the percentage of responders and global tolerability and efficacy were evaluated.

Results

The mean GAGS score was reduced by 21.72% and 14.20% on day 28 in RGLE (n=10) and placebo groups (n=12), respectively, which further reduced in both groups on day 56. The RGLE group reported better improvement in other skin characteristics on day 56. No safety or tolerability concerns were reported for the extract. RGLE reduced acne and improved the skin quality in females compared to placebo as early as 28 days of supplementation.

Conclusion

RGLE supplementation at a dose of 100 mg/day has provided a clinically relevant decrease in acne severity and improved the skin hydration and quality of life of the participants with acne after 56 days of dose administration.

Keywords:

• acne
• healthy skin
• herbal extract
• Rehmannia glutinosa
• quality of life

Abbreviations

CONSORT, Consolidated Standards Of Reporting Trials; EC, Ethics Committee; GAGS, Global Acne Grading System; GMP, Good Manufacturing Practice; IP, Investigational Product; ICH-GCP, International Conference On Harmonization - Good Clinical Practice; MFWS, Modified Fitzpatrick Wrinkle Severity Scale; NRS, Numeric Rating Scale; RGLE, Rehmannia glutinosa libosch leaf extract; TSH, Thyroid Stimulating Hormone; UPT, Urine Pregnancy Test; VAS, Visual Analog Scale.

Data Sharing Statement

The data presented in the study is available at a reasonable request from the corresponding author.

Acknowledgments

The authors thank all the participants who volunteered for the study. The authors express their gratitude to NuLiv Science USA Inc. for providing the study products and funds for executing the study. The authors acknowledge Vedic Lifesciences for facilitating the study.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

Shalini Srivastava is affiliated with Vedic Lifesciences Pvt. Ltd. Shu Fen Huang is an employee of NuLiv Holding Inc. Manjiri S Jagtap is affiliated with Skin Cure n Care Clinic. The authors report no other conflicts of interest in this work.

Additional information

Funding

NuLiv Science USA Inc. provided the study products and sponsored the study.