Serum Substance P, Neuropathic Pain, and Central Sensitization Across Treatment Groups in Chronic Plaque Psoriasis
Evaluation of the Association of Serum Substance P Levels With Neuropathic Pain, Central Sensitization, Disease Severity, and Quality of Life Across Different Treatment Groups in Patients With Chronic Plaque Psoriasis
- Chronic Plaque-type Psoriasis
At a glance
- Phase
- Phase not stated
- Study type
- Observational
- Sponsor
- Istanbul Training and Research Hospital
- Enrolment target
- 100
- Started
- 11 June 2026
- Main results due
- December 2026
- Study sites
- 1
- Registry updated
- 28 September 2026
Can you take part?
- Aged 18 years and over.
- Open to any sex.
- You need the condition being studied — healthy volunteers are not accepted.
These are the headline rules only. Every study has a longer list, and whether you are eligible is decided by the research team at the site — never by this page.
Read the full eligibility criteria
Inclusion Criteria: * Age ≥18 years * Diagnosis of chronic plaque psoriasis * Ability and willingness to provide written informed consent * For the IL-17 inhibitor group: current treatment with an IL-17 inhibitor for at least 8 weeks * For the conventional systemic therapy group: current treatment with methotrexate or acitretin for at least 6 weeks * For the topical therapy/treatment-naive group: topical therapy only or no previous treatment, with no systemic therapy, biologic therapy, or phototherapy within the previous 6 months Exclusion Criteria: * Known diabetes mellitus, HbA1c ≥6.5%, or fasting plasma glucose ≥126 mg/dL * Vitamin B12 level \<200 pg/mL * Known peripheral neuropathy or peripheral neuropathy detected during neurological evaluation and/or electromyography * Neuropathy related to uremia or thyroid disease * Chronic renal failure or chronic liver failure * Active infection * Active malignancy * Active inflammatory arthritis in patients with psoriatic arthritis * Pregnancy or breastfeeding * Chronic heavy alcohol use
What this study is about
In the sponsor’s own words, from the registry.
The goal of this observational study is to better understand whether blood levels of Substance P are related to pain, itching, altered pain sensations, central sensitization, psoriasis severity, and quality of life in adults with chronic plaque psoriasis.
The main questions this study aims to answer are:
Are serum Substance P levels associated with neuropathic pain features, central sensitization, psoriasis severity, pain, itching, and quality of life? Do serum Substance P levels and these clinical features differ among patients receiving different psoriasis treatments?
Researchers will compare three groups of patients: those receiving IL-17 inhibitor treatment, those receiving conventional systemic treatment with methotrexate or acitretin, and those receiving topical treatment only or no current treatment.
Participants will:
Have their psoriasis severity assessed and complete questionnaires about pain, itching, central sensitization, and quality of life.
Undergo a neurological examination. Participants who report pain will also be evaluated for neuropathic pain features using the DN4 questionnaire.
Provide a blood sample for measurement of serum Substance P and routine laboratory tests.
Undergo electromyography and nerve conduction studies if peripheral neuropathy is suspected during the neurological evaluation.
No treatment will be assigned or changed as part of this study.
Study sites(1)
Istanbul Training and Research Hospital
Istanbul, Istanbul, Turkey (Türkiye)
Recruiting
Showing 1 of 1 sites. 1 of the 1 site on this study is recruiting right now — a site can stop enrolling while the study as a whole is still open.
Source: ClinicalTrials.gov record NCT07844772. Trialion does not run this study, is not paid to refer anyone to it, and cannot enrol you. Eligibility is always decided by the research team at the site.
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