A prospective, multi-center, observational biomarker real-world evidence study for in-depth profiling of patients with chronic immune-mediated inflammatory skin diseases in daily practice

1.1 Atopic dermatitis (AD)
Atopic dermatitis (AD) is an inflammatory skin disorder that causes a dry skin
that itches. The pathophysiology of AD is complex and still not completely
understood. Genetic susceptibility, environmental factors, epidermal barrier
abnormalities, immunological disturbances and dysbiosis of the skin microbiota
all play a role in the disease and the variability of these mechanisms may
explain the heterogeneous character of AD. It remains hard to discern which of
these mechanisms are primary events (causing AD), secondary events (resulting
from AD), or both (Weidinger et al., 2018). The value of blood-based biomarkers
and skin biopsies in patients treated with systemic immunosuppressants and
biologics in AD has been explored to a limited extent. For example, analysis of
gene expression in skin biopsies has revealed important information regarding
molecular pathways responsible for driving disease pathology in a wide variety
of inflammatory skin conditions, including AD. Additional research on
biomarkers in AD could have a major impact on the understanding of AD, which
could be incorporated into clinical patient care setting.

1.2 Cutaneous lupus erythematosus (CLE)
Cutaneous lupus erythematosus (CLE) is an autoimmune disease that can occur
isolated to the skin or as a manifestation of systemic lupus erythematosus
(SLE) (Stannard and Kahlenberg, 2016). Subtypes of CLE, which differ in lesion
morphology and histopathology, include acute cutaneous LE (ACLE), subacute
cutaneous LE (SCLE), intermittent cutaneous LE (ICLE) i.e., lupus tumidus (LET)
and chronic cutaneous LE (CCLE). CCLE can be further subdivided into various
subtypes including (but not limited to) cutaneous discoid LE (CDLE) and LE
profundus (LEP). The pathogenesis and pathophysiology of CLE are not fully
understood. Given the complex and heterogeneous character of the disease,
identification, and development of specific biomarkers for diagnosis, disease
subtyping, disease severity, and treatment response in CLE is challenging. Only
few biomarkers for CLE have been validated and widely incorporated into
clinical practice (Zhu et al., 2021). Type I interferon-inducible proteins can
be potentially used to assess disease severity of SCLE and CDLE (Braunstein et
al., 2013). Furthermore, low complement in CLE patients may be related to poor
prognosis and increased risk of developing systemic disease (Vera et al., 2010).

1.3 Chronic spontaneous urticaria (CSU)
Chronic spontaneous urticaria (CSU; also known as chronic idiopathic urticaria)
is an inflammatory skin condition characterized by the development of systemic
itchy red hives (wheals), with or without deep tissue swelling (angioedema) for
a period of >=6 weeks (Zuberbier 2022) with no specific evocating factor. The
hives and angioedema that are associated with CSU are directly attributable to
degranulation of mast cells. This can be triggered by numerous different
stimuli. The pathogenesis of CSU is not completely understood, and there is a
strong need for novel biomarkers for disease endotyping and prediction of
treatment response.

1.4 Hidradenitis suppurativa (HS)
Hidradenitis suppurativa (HS) is significantly impacts patients* quality of
life more than many other dermatological diseases. Globally, its prevalence is
around 4% (Jfri et al., 2021). HS is more common in women and is frequently
associated with obesity, smoking, diabetes mellitus, inflammatory bowel
disease, and metabolic syndrome (Barlev et al., 2015).

The disease begins with follicular occlusion in the folliculo-pilosebaceous
unit, leading to rupture and an immune response. This response involves the
activation of neutrophilic granulocytes, macrophages, and plasma cells, along
with pro-inflammatory cytokines such as interleukins (IL-1β, IL-17), tumor
necrosis factor (TNF), and interferon (IFN-γ), creating a vicious cycle of
tissue destruction (Khandalavala et al., 2016; McCarthy et al., 2022). HS is a
painful, recurrent condition affecting soft tissue in intertriginous regions
like the axillae, perianal and perineal areas, buttocks, groins, sub-mammary
area, and genitals in women (Ingram, 2016; Ezanno et al., 2021). Lesions can
vary from nodules and abscesses to draining malodorous sinuses, and may
progress to scarring, open comedones, and fistulas (Margesson & Danby, 2014).

Treating HS is extremely challenging due to the lack of a universally accepted
standard of care and a high recurrence rate, which frustrates both patients and
clinicians. Treatment strategies aim to control inflammation, scarring, and
related comorbidities, and include topical and systemic medications, biologics,
and surgical interventions. Despite the wide range of treatments, no single
approach has proven universally effective.
The impact on patients* quality of life is significant, and managing the
psychosocial aspects is crucial, as HS is associated with pain, severe
discomfort, and embarrassment, profoundly affecting social and mental
functioning. Additionally, a lack of awareness among healthcare professionals
can lead to misdiagnosis and delays in appropriate treatment, worsening the
disease.

1.5 Cutaneous T-cell lymphoma (CTCL) subtype mycosis fungoides (MF)
Cutaneous T-cell lymphomas (CTCL) are primary T-cell derived cutaneous
lymphomas; they
represent a group of lymphoproliferative disorders characterized by
localization of neoplastic T lymphocytes to the skin. This may result in skin
patches and plaques, erythroderma, itch, dry skin and hair loss. In advanced
stages tumors in the skin occur often associated with cutaneous and systemic
infections. Mycosis fungoides (MF), which is generally indolent in behaviour,
and Sézary syndrome (SS), an aggressive and leukemic variant, comprise
approximately 53% of all primary cutaneous lymphomas and two-third of CTCL
(Willemze et al., 2019). Staphylococcus aureus (S. aureus) and its toxins have
been shown to positively correlate with progression and colonize 31% to 76% of
patients across all stages and subtypes (Fujii, 2021). Staging and diagnosing
the progression of CTCL are key to defining an effective treatment strategy.
Current treatment strategies for CTCL are diverse, focusing on anti-tumor
activity and infection and/or rash treatment. CTCL is a group of malignancies
that is a subset of non-Hodgkin lymphomas derived from skin-homing T cells with
no evidence of extracutaneous disease at the time of diagnosis. MF and SS are
the most common CTCL variants (Bastidas Torres et al., 2018; Willemze et al.,
2019). MF is the most prevalent (up to 60%) clinical form of CTCL and is
characterized by proliferation of malignant skin-homing T cells in a chronic
inflammatory environment in the skin. Only limited information is available
about biomarkers for the relationship between CTCL variants, its staging,
clinical symptoms and therapeutic response.

1.6 Plaque psoriasis (PSO)
Psoriasis is a common skin disorder affecting up to an estimated 3% of the
world*s population. The most prevalent form of psoriasis, called psoriasis
vulgaris or plaque psoriasis, is characterized by the presence of sharply
demarcated erythematous plaques covered with white scales. These lesions can
occur all over the body, but are most often seen on the extensor surface of the
joints, nether regions and on the scalp. Patients can experience excessive
itch, pain and sometimes bleeding of the lesions. Moreover, the visual
appearance of psoriatic lesions can severely impact the patients psychological
state and quality of life (Boehncke and Schön, 2015). An abundancy of different
factors contributes to the pathogenesis of psoriasis. However, aberrant
inflammatory reactions in the skin are thought to be the underlying cause.
Excessive infiltration of immune cells in the skin and their interactions with
cutaneous resident cells results in the hyper proliferati

The objective of the Next Generation ImmunoDermatology project (funding NWO,
program NWA-ORC) is to deep profile immune-mediated inflammatory diseases for
the identification of biomarkers that can identify different disease endotypes
that can predict treatment response to enable future personalization of care. A
major part of the project is dedicated to this prospective observational study
in daily practice. Aim is the comprehensive, multi-modal characterization of
six relevant immune-mediated inflammatory skin diseases: i) atopic dermatitis
(AD), ii) cutaneous lupus erythematosus (CLE) iii) chronic spontaneous
urticaria (CSU) iv) hidradenitis suppurativa (HS) v) cutaneous T-cell lymphoma
(CTCL) subtype mycosis fungoides (MF) and vi) plaque psoriasis (PSO). The
investigations will profile various aspects of the disease including
patient-reported outcomes, the clinician-reported outcomes, biophysical,
imaging, cellular, microbiological and molecular biomarkers.

Primary objectives
• To identify discriminative biomarkers for predictivity of treatment
(non)response
• To evaluate disease-related biomarkers compared to healthy volunteers
• To evaluate (multi-omics) biomarkers for disease stratification and
(targeted) treatment (non)response in daily practice of patients with AD, CLE,
CSU, HS, MF and PSO

Secondary objectives
• To compare biomarkers between different patient cohorts
• To evaluate changes in biomarkers upon treatment over time

Exploratory objectives
• To identify biomarkers in skin tissue that correlate with disease progression
or therapy response
• To evaluate and compare genome profiles of patients
• To include additional (imaging) biomarkers in comparison of profiles and over
time

Disease specific objectives entail:
- Identification and evaluation of predictability of biomarkers of disease
subtypes for efficacy and effectiveness of CsA, anti-IL4/IL13 and
JAK1-inhibitors for AD
- Identification and evaluation of predictability of biomarkers of disease
subtypes for efficacy and effectiveness of topical corticosteroids,
hydroxychloroquine, and methotrexate for patients with CLE
- Identification and evaluation of predictability of biomarkers of disease
subtypes for efficacy and effectiveness of anti-IgE, cyclosporine A, and
anti-BTK** for patients with CSU
- Identification and evaluation of predictability of biomarkers of disease
subtypes for efficacy and effectiveness of anti-TNF, and anti-IL17 for patients
with HS
- Identification and evaluation of predictability of biomarkers of disease
subtypes for efficacy and effectiveness of topical chlormethine, topical
corticosteroids, and phototherapy (PUVA/UV-B) for patients with cutaneous
T-cell lymphoma subtype MF
- Identification and evaluation of predictability of biomarkers of disease
subtypes for efficacy and effectiveness of anti-TNF, anti-IL17, anti-TYK2 and
anti-IL23 for patients with PSO
**once approved and reimbursed in the Netherlands

This is a multicenter, parallel-cohort, open-label, observational, longitudinal
biomarker study in real-world setting, in daily practice with an observation
period of 1 year (Figure 2). Healthy subjects will serve as a control cohort
for the disease cohorts at baseline. In total 720 patients will be followed for
one year after commencement of real-world treatment in the regular healthcare.
Multimodal parameters will be evaluated pre-dose, at month 3 (week 12-16);
month 6 (week 24-28) and month 12 (week 52±3 weeks). An exploratory study will
be conducted upon obtaining consent of the patient. In this study, additional
biomarkers will be incorporated. Moreover, 120 healthy volunteers will be
followed for six weeks. Multimodal parameters will be evaluated at week 1 and
week 6 (±1 week).

Biopsies with a size of four millimeters in diameter are taken to assess
histology,
immunohistochemistry and perform imaging mass cytometry analysis from one
biopsy. Biopsies of this small size generally do not need stitching in order to
heal. Biopsy can possibly leave a lasting mark on the skin, therefore healthy
subjects with a history of hypertrophic scarring or keloid will be excluded.
For patients biopsy collection is performed at day 1 and at EOS (all
optionally). Results from these time points will provide a comprehensive
overview on how disease characteristics and biomarkers of skin will change
prior and after treatment. Healthy volunteers will only undergo a single biopsy
at day 1 as they will only participate as control group.

In summary, the risk of participating in the trial can be assessed as low and
are acceptable.