Systemic sclerosis (SSc) is a rare autoimmune disease characterised by skin and organ fibrosis, vasculopathy and immune dysregulation. Given the disease heterogeneity and severity, accurate prognostic and predictive markers are needed. Blood immunophenotyping by flow or mass cytometry offers a promising non-invasive approach to identify immune signatures associated with disease subtypes, complications (eg, interstitial lung disease, scleroderma renal crisis, digital ulcers) and treatment responses. However, findings remain inconsistent and lack clinical standardisation. This systematic review aims to identify cytometry-based blood immune markers associated with clinical outcomes in SSc.

A comprehensive search will be conducted on three databases: PubMed, Web of Science and Cochrane Library, from their inception to the date of the final search (21 December 2025). Data will be extracted and analysed using a predefined charting form. Studies published in English or French reporting the use of flow or mass cytometry for peripheral blood cells phenotyping in adults with SSc will be included. Comparators will include healthy controls, other autoimmune diseases, disease severity groups and treatment response subgroups. The primary outcome will be the association with the diffuse cutaneous subtype, while secondary outcomes will include overall survival and disease-specific mortality, organ involvement, progression of the disease and treatment response.

Ethical approval is not required as this review is an analysis of published scientific literature and does not involve patients. The results of this systematic literature review will be submitted for publication in a peer-reviewed journal and presented at relevant conferences.

CRD420250644594.

Pain accounts for approximately 80% of emergency department admissions. While intravenous morphine titration is commonly used for severe pain, non-invasive alternatives that bypass intravenous access are needed. Nebulised fentanyl, combined with pupillometry for objective monitoring of opioid impregnation, may offer a rapid and safe alternative for pain management.

This phase I, open-label, randomised, exploratory, crossover, single-centre prospective controlled trial will employ pharmacokinetic–pharmacodynamic (PK–PD) modelling to assess the variability in bioavailability of nebulised fentanyl administered via intranasal route versus facial aerosol. 20 healthy volunteers will receive three repeated administrations of fentanyl over two visits. At each visit, blood samples (n=11) will be collected for fentanyl quantification by liquid chromatography–tandem mass spectrometry, and pupillary unrest in ambient light (PUAL) measurements (n=9) will be recorded. The resulting data will be analysed using Monolix 2024R1 to model PK–PD relationships, perform Monte Carlo simulations and determine the optimal dosing and timing required to achieve a reduction of more than 30% in PUAL, while also evaluating safety, comfort and tolerance.

The study has been approved by the Ethic Committee Île-de-France VII (approval reference number: 000216, February 2024) and will be conducted in accordance with the Declaration of Helsinki. Informed consent will be obtained from all participants. Study findings will be disseminated through peer-reviewed publications, conference presentations and appropriate data-sharing platforms to support further research and clinical application.

This trial is registered at ClinicalTrials.gov (Identifier: NCT06281951).