Correlation Between Circulating Fibroblast Activation Protein (FAP) and Fibrosis in Two Diseases (Rheumatoid Arthritis and Systemic Sclerosis)

Circulating Fibroblast Activation Protein (FAP) As A Marker for Fibroblast-Driven Pathology in Rheumatoid Arthritis and Systemic Sclerosis : Implication for Joint, Skin and Lung Fibrosis

Status

Not yet recruiting

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT07393217

Acronym

FAP

Enrollment

111

Registered

2026-02-06

Start date

2026-03-01

Completion date

2027-09-01

Last updated

2026-02-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Rheumatoid Arthritis (RA), Systemic Sclerosis (SSc)

Keywords

Fibroblast Activation protein, Rheumatoid Arthritis, systemic sclerosis, lung fibrosis, skin fibrosis

Brief summary

This study aims to measure a blood protein called fibroblast activation protein (FAP), which is linked to tissue scarring and inflammation. A small blood sample will be taken from participants (RA , SSc patients and healthy people ), and the FAP level will be measured and compared with routine clinical examinations, imaging studies, and lung function tests. The purpose of this study is to improve understanding of disease activity and lung involvement in these conditions and to explore whether FAP could be useful as a blood marker for future patients. Participation in this study will not change the participant's usual medical care.

Interventions

None listed

Study design

Observational model

CASE_CONTROL

Time perspective

CROSS_SECTIONAL

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Yes

Inclusion criteria

* Age ≥18 years. Confirmed diagnosis of RA (ACR/EULAR) or SSc (ACR/EULAR). * Ability and willingness to provide informed consent. Cooperative patient able to answer questions.

Exclusion criteria

* Patients under 18 years' old * Active cancer or history of cancer within 5 years. * Other major fibrotic systemic disease that could confound circulating FAP levels. * Acute infection at time of sampling. * Pregnancy or breastfeeding. * Other autoimmune diseases

Design outcomes

Primary

Measure	Time frame
Serum fibroblast activation protein (FAP) concentration measured by ELISA in patients with rheumatoid arthritis and systemic sclerosis	At baseline (Day 1)

Secondary

Measure	Time frame	Description
disease activity	baseline	Correlation between serum FAP concentration and disease activity score in rheumatoid arthritis and systemic sclerosis
pulmonary involvement	baseline	Correlation between serum FAP concentration and pulmonary involvement in patients with rheumatoid arthritis and systemic sclerosis

Countries

Egypt

Outcome results