Effects of Diet and Oxidative Stress on Disease Severity and Response to Omalizumab in Chronic Spontaneous Urticaria

NCT07431658 | Enrolling By Invitation

• 1 other identifier: SBU-IEAH-KAEK-20251205-294
• Study Type: observational
• Target: 116
• Locations: 1 country
• Sites: 1

Brief Summary

Chronic spontaneous urticaria (CSU) is an immune-mediated skin disorder characterized by pruritic wheals and/or angioedema. This study aims to evaluate the relationship between diet-derived antioxidant capacity and oxidative stress with CSU presence, disease activity, and response to omalizumab. Adults with active CSU and age/BMI-matched healthy controls will provide non-consecutive 3-day dietary records (two weekdays and one weekend day). Dietary antioxidant capacity will be calculated using ORAC metrics via BeBiS software. Oxidative stress biomarkers (total oxidant status, total antioxidant status, oxidative stress index, malondialdehyde, and advanced oxidation protein products) will be measured from venous blood samples. CSU disease activity will be assessed using UAS7 and UCT, along with an urticaria quality of life questionnaire. In CSU patients who receive omalizumab as clinically indicated, assessments will be repeated after 3 months to evaluate treatment response and associated changes in diet and oxidative stress markers.

Conditions

Chronic Spontaneous Urticaria (CSU)

Keywords

Chronic spontaneous urticaria; oxidative stress; dietary antioxidant capacity; omalizumab; UAS7; UCT; AOPP; MDA; total oxidant status; total antioxidant status; OSI; ORAC

Outcome Measures

Primary Outcomes (3)

• Disease activity scores (UAS7, UCT) and urticaria quality of life questionnaire (CU-Q2oL)

  Disease activity and control will be assessed in CSU patients only using the Urticaria Activity Score over 7 days (UAS7) and Urticaria Control Test (UCT). Quality of life will be assessed in CSU patients only using an urticaria quality of life questionnaire (CU-Q2oL)

  Baseline

• Oxidative stress biomarkers (TOK, TAK, AOPP, MDA; OSI calculated)

  From routine venous blood samples, Total Oxidant Capacity (TOK), Total Antioxidant Capacity (TAK), Advanced Oxidation Protein Products (AOPP), and Malondialdehyde (MDA) will be measured; Oxidative Stress Index (OSI) will be calculated as the TOK/TAK ratio.

  Baseline

• Dietary intake / dietary antioxidant capacity based on 3-day dietary record

  Dietary intake will be captured using three non-consecutive 24-hour dietary records (two weekdays, one weekend day). Dietary antioxidant capacity will be calculated using Oxygen Radical Absorbance Capacity (ORAC) with BeBiS 9.0 (Nutrition Information System).

  Baseline

Secondary Outcomes (2)

• Change in urticaria disease activity score (UAS7: Urticaria Activity Score over 7 days), urticaria control (UCT: Urticaria Control Test) and urticaria-related quality of life questionnaire score (CU-Q2oL)

  Baseline to 3 months (after initiation of omalizumab)

• Change in oxidative stress biomarkers in venous blood (TOK, TAK, AOPP, MDA, OSI)

  Baseline to 3 months after initiation of omalizumab

Other Outcomes (1)

• Associations between dietary variables, oxidative stress biomarkers, and clinical outcomes in CSU

  Baseline (and Baseline to 3 months after omalizumab in CSU patients)

Study Arms (2)

Cohort 1: Chronic Spontaneous Urticaria (CSU) Patients

58 adults with active CSU

Cohort 2: Healthy Controls

58 healthy volunteers matched by age and BMI

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adults with active CSU and age/BMI-matched healthy volunteers

You may qualify if:

• Age 18-65 years
• CSU group: diagnosis of chronic spontaneous urticaria, active CSU, and written informed consent
• Control group: healthy volunteers with similar characteristics (age/BMI-matched)

You may not qualify if:

• Additional dermatologic, metabolic, endocrinologic, systemic inflammatory disease; malignancy (diagnosis or suspicion)
• Use within last 3 months of anti-inflammatory drugs or drugs that may affect serum glucose/lipids
• Special diet/nutrition status; antioxidant supplement use
• Smoking or alcohol use
• Pregnant or breastfeeding

Sponsors & Collaborators

• Istanbul Training and Research Hospital: lead

Study Sites (1)

Istanbul Training and Research Hospital, Dermatology and Venereology Clinic Cerrahpaşa Mh. Org. Abdurrahman Nafiz Gürman Cd. No:24, 34098 Fatih, Istanbul, Turkey

Istanbul, 34098, Turkey (Türkiye)

Location

Biospecimen

Retention: SAMPLES WITH DNA

Blood (venous blood for oxidative stress biomarkers)

MeSH Terms

Conditions

Chronic Urticaria

Condition Hierarchy (Ancestors)

Urticaria; Skin Diseases, Vascular; Skin Diseases; Skin and Connective Tissue Diseases; Hypersensitivity, Immediate; Hypersensitivity; Immune System Diseases; Chronic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Dermatology Resident

Study Record Dates

• First Submitted: February 19, 2026
• First Posted: February 24, 2026
• Study Start: December 1, 2025
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): March 1, 2027
• Last Updated: February 27, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)