A Clinical Trial to Compare the Photoprotective Effects of Cucumber Seed Extract vs Placebo in Filipino Adults by Measurement of Minimal Erythema Dose

NCT07719413 | Completed DMC

• 1 other identifier: REC-2024-00086
• Study Type: interventional
• Target: 29
• Locations: 1 country
• Sites: 1

Brief Summary

A monocentric, randomized, split-body, double-blind, controlled trial was conducted on 29 Filipino adults with Fitzpatrick skin types III-V. Topical 2% and 4% cucumber seed extract gels and placebo were applied to randomized sites on the lower back, followed by incremental narrow-band UVB exposure. MED was assessed 24 hours post-exposure. Repeated measures ANOVA and paired t-tests were used for statistical analysis.

Conditions

Healthy Human Volunteers With Fitzpatrick Skin Type III-V; Sunburn, Erythema

Outcome Measures

Primary Outcomes (1)

• Change in minimal erythema dose (MED) after application of 2% and 4% cucumber seed extract compared with placebo

  After 24 hours post-application, the principal investigator examined previously irradiated sites. A well-defined erythematous response at the lowest NBUVB dose was recorded as the MED, corresponding to E2 on the Visual Erythema Scale.

  24 hours post application

Secondary Outcomes (1)

• Adverse events such as pain, pruritus, tenderness, burning, blistering, or irregular pigmentation (Composite secondary outcome)

  24 and 48 hours after application

Study Arms (3)

Randomized Test Site on Back 1

EXPERIMENTAL

Three test sites were delineated on each participant's lower back, and study treatments were randomly allocated to these sites using computer-generated randomization performed by a dermatology resident not involved in the trial. Three MED test patches were applied on three sun-protected areas on the lower back. The test patch had six windows of uniform sizes (2 cm × 2 cm) that were opened and exposed one at a time to incremental doses of excimer light. The gels were applied by the research assistant on the designated randomized areas on the lower back. The assistant researcher then applied the respective gels at an amount of 2 mg/cm2 (1/4 teaspoon) on each of the three test sites. Gels were massaged to the skin until fully absorbed.

Drug: Placebo gel; Drug: 2% cucumber seed gel; Drug: 4% cucumber seed gel

Randomized Test Site on Back 2

EXPERIMENTAL

Drug: Placebo gel; Drug: 2% cucumber seed gel; Drug: 4% cucumber seed gel

Randomized Test Site on Back 3

PLACEBO COMPARATOR

Drug: Placebo gel; Drug: 2% cucumber seed gel; Drug: 4% cucumber seed gel

Interventions

2% cucumber seed gel DRUG

Cucumber seed gel preparations were compounded by an FDA-registered pharmaceutical company which were incorporated into the placebo base gel at 2% concentration. The assistant researcher then applied 2% cucumber seed gel at an amount of 2 mg/cm2 (1/4 teaspoon) on the designated randomized test site.

Randomized Test Site on Back 1; Randomized Test Site on Back 2; Randomized Test Site on Back 3

4% cucumber seed gel DRUG

Cucumber seed gel preparations were compounded by an FDA-registered pharmaceutical company which were incorporated into the placebo base gel at 4% concentration. The assistant researcher then applied 4% cucumber seed gel at an amount of 2 mg/cm2 (1/4 teaspoon) on the designated randomized test site.

Randomized Test Site on Back 1; Randomized Test Site on Back 2; Randomized Test Site on Back 3

Placebo gel DRUG

The placebo gel serves as the base formulation is composed of: the oil phase of the formulation comprising of octadecanol, stearic acid, and liquid paraffin, while the aqueous phase consisted of distilled water, glycerin, and ethylparaben. The two phases were emulsified and combined to make the base gel. The assistant researcher then applied placebo gel at an amount of 2 mg/cm2 (1/4 teaspoon) on the designated test site.

Randomized Test Site on Back 1; Randomized Test Site on Back 2; Randomized Test Site on Back 3

Eligibility Criteria

• Age: 18 Years - 59 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• \- Filipinos aged 18 to 59 years with Fitzpatrick skin phototypes III to V were included in the study.

You may not qualify if:

• Elderly and pediatric populations were excluded due to differences in skin structure, immune responses, and the presence of age-related comorbidities that may confound study findings.
• Had a history of phototoxic, photoallergic, or abnormal responses to sunlight; ----Reported allergies to cosmetic products, sunscreens, topical drugs, cucumber, or any study formulation component
• Participants were also excluded if they presented with pre-existing or dormant dermatologic conditions, sunburn, suntan, scars, active lesions, or uneven pigmentation on the lower back.

Sponsors & Collaborators

• DOH - Tondo Medical Center: lead

Study Sites (1)

DOH-Tondo Medical Center Department of Dermatology and Venereology

Manila, National Capital Region, 1003, Philippines

Location

MeSH Terms

Conditions

Sunburn; Erythema

Condition Hierarchy (Ancestors)

Photosensitivity Disorders; Skin Diseases; Skin and Connective Tissue Diseases; Burns; Wounds and Injuries; Skin Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: July 17, 2026
• First Posted: July 22, 2026
• Study Start: January 27, 2025
• Primary Completion: February 26, 2025
• Study Completion: February 28, 2025
• Last Updated: July 31, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR
• Time Frame: From: At the end of the study End: No end date

Locations

PH (1)