Quantifying the natural variation in lesion counts over time in untreated hidradenitis suppurativa: Implications for outcome measures and trial design

Data wobbles in hidradenitis suppurativa clinical trials and potential contributing factors: a retrospective review

Background

In some hidradenitis suppurativa (HS) clinical trial study arms, there is an unexpected decline in efficacy between the penultimate visit and the prespecified primary endpoint week, which we have termed a "wobble."

Objective

We aimed to establish how often study arms in HS programs wobble.

Methods

In a retrospective review, we identified HS clinical trials listed on ClinicalTrials.gov testing systemic, nonantibiotic medications that utilized Hidradenitis Suppurativa Clinical Response (HiSCR) as an outcome measure. We identified study arms demonstrating greater improvement in a visit prior to the primary endpoint week. Baseline subject characteristics were compared between studies with HiSCR wobble and no HiSCR wobble.

Results

A total of 21 studies (randomized control trial [RCT], n = 14; open-label, n = 7) with 35 study drug arms (RCT, n = 27; open-label, n = 8) and 14 placebo arms were identified. HiSCR wobble occurred significantly more often in RCT compared to open-label study drug arms (11/27 [40.7%] vs 0/8 [0%]). In RCT study arms with HiSCR wobble, baseline draining fistula counts were significantly lower (2.3 vs 3.2), and numerically fewer Hurley stage 3 patients (33.2% vs 42.5%), lower weighted total abscess and nodule counts (12.1 vs 12.6), lower weighted dermatology life quality index scores (12.5 vs 14.5), and a higher proportion of female patients (63.9% vs 58.3%) were observed.

Limitations

Include low number of HS clinical trials and insufficient data reported in many studies to assess for wobble, degree of wobble, and to compare all baseline characteristics.

Conclusion

Nonlinear improvement in study arm response occurs in some HS RCTs. Potential contributing factors include a higher proportion of less severe patients at baseline and more female patients.

A proof-of-concept open-label clinical trial of spleen tyrosine kinase antagonism using fostamatinib in moderate-to-severe hidradenitis suppurativa

BACKGROUND

Hidradenitis suppurativa (HS) is an autoinflammatory disorder of keratinization with a prominence of B cells and plasma cells. Fostamatinib is a spleen tyrosine kinase inhibitor targeting B cells and plasma cells.

OBJECTIVES

To assess the safety, tolerability, and clinical response at week 4 and week 12 of fostamatinib in moderate-to-severe HS.

METHODS

Twenty participants were administered fostamatinib 100 mg twice a day for 4 weeks, escalating to 150 mg twice a day thereafter until week 12. Participants were assessed for adverse events and clinical response assessed by HiSCR (Hidradenitis Suppurativa Clinical Response Score) and IHS4 (International Hidradenitis Suppurativa Severity Score) as well as other outcomes including DLQI (Dermatology Life Quality Index), visual analog scale, and physician global assessment.

RESULTS

All 20 participants completed the week 4 and week 12 endpoints. Fostamatinib was well tolerated in this cohort with no grade 2/3 adverse events reported. A total of 85% achieved HiSCR at week 4 and 85% at week 12. The greatest reduction in disease activity was seen at weeks 4/5 with worsening in a proportion of patients thereafter. Significant improvements were seen in pain, itch, and quality of life.

CONCLUSIONS

Fostamatinib was well tolerated in this HS cohort with no serious adverse events and improvement in clinical outcomes. Targeting B cells/plasma cells may be a viable therapeutic strategy in HS and requires further exploration.

Guselkumab for the treatment of patients with moderate-to-severe hidradenitis suppurativa: A phase 2 randomized study

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition that causes substantial physical, emotional and psychological burdens. Guselkumab, a monoclonal antibody that binds to the p19 subunit of interleukin-23, has demonstrated high levels of efficacy in the treatment of inflammatory diseases, including psoriasis and psoriatic arthritis.

OBJECTIVE

To evaluate the effect of guselkumab on the treatment of HS, a phase 2, multicentre, randomized, placebo-controlled, double-blind, proof-of-concept study was conducted.

METHODS

Patients ≥18 years of age with moderate-to-severe HS for ≥1 year were randomized to (1) guselkumab 200 mg by subcutaneous (SC) injection every 4 weeks (q4w) through Week 36 (guselkumab SC); (2) guselkumab 1200 mg intravenously (IV) q4w for 12 weeks, then switched to guselkumab 200 mg SC q4w from Weeks 12 through 36 (guselkumab IV); or (3) placebo for 12 weeks, with re-randomization to guselkumab 200 mg SC q4w at Weeks 16 through 36 (placebo → guselkumab 200 mg) or guselkumab 100 mg SC at Weeks 16, 20, 28 and 36 and placebo at Weeks 24 and 32 (placebo → guselkumab 100 mg). End points included HS clinical response (HiSCR) and patient-reported outcomes.

RESULTS

Although guselkumab SC or guselkumab IV resulted in numerically higher HiSCR versus placebo at Week 16 (50.8%, 45.0%, 38.7%, respectively), statistical significance was not achieved. Numerically greater improvements in patient-reported outcomes were also observed for guselkumab SC and guselkumab IV versus placebo at Week 16. Through Week 40, no clear differences to suggest a dose response were observed for HiSCR and patient-reported outcomes.

CONCLUSIONS

Despite modest improvements, the primary end point was not met and the overall findings do not support the efficacy of guselkumab in the treatment of HS.

CLINICALTRIALS

gov: NCT03628924.

Development and validation of IHS4-55, an IHS4 dichotomous outcome to assess treatment effect for hidradenitis suppurativa

BACKGROUND

Validated, inclusive and easy-to-use outcomes for hidradenitis suppurativa are essential both in the clinical trial setting and clinical practice. The continuous IHS4 is a validated tool that dynamically assesses nodules/abscesses/draining tunnels and classifies disease severity as mild/moderate/severe. However, dichotomous outcomes are often required for clinical trials reporting.

OBJECTIVE

To develop and validate a dichotomous outcome based on IHS4 that can be used in clinical trial settings and day-to-day clinical practice.

METHODS

De-identified data from the PIONEER-I and -II studies were accessed through Vivli. Potential IHS4 thresholds were analysed using baseline to Week 12 data from adalimumab- and placebo-treated hidradenitis suppurativa patients in the PIONEER-I trial. The final threshold was chosen based on its ability to discriminate between patients treated with adalimumab or placebo and its association with reduction in inflammatory lesions. The final threshold was validated using data from baseline to Week 12 from adalimumab- and placebo-treated hidradenitis suppurativa patients in both the PIONEER-II and the combined PIONEER-I and -II studies.

RESULTS

The best performing cut-off for the IHS4 was a 55% reduction of the IHS4 score (IHS4-55). Patients who achieved the IHS4-55 had an odd's ratio of 2.00 [95%-CI 1.26-3.18, p = 0.003], 2.79 (95%-CI 1.76-4.43, p < 0.001) and 2.16 (95%-CI 1.43-3.29, p < 0.001) for being treated with adalimumab rather than placebo in PIONEER-I, PIONEER-II and the combined dataset, respectively. Additionally, the achievement of the IHS4-55 was associated with a significant reduction in inflammatory nodules, abscesses and draining tunnels in all analysed datasets.

CONCLUSIONS

IHS4-55, a novel dichotomous IHS4 version, based on a 55% reduction of the total score was developed. The IHS4-55 performs similarly to the HiSCR in discriminating between adalimumab- and placebo-treated hidradenitis suppurativa patients and shows significant associations with reductions in lesion counts. Moreover, the IHS4-55 addresses some of the HiSCR drawbacks by dynamically including draining tunnels in a validated manner. By allowing the analysis of hidradenitis suppurativa patients with an abscess and nodule count below 3 but many draining tunnels, this outcome measure will improve inclusivity in clinical trials.

Overview and comparison of the clinical scores in hidradenitis suppurativa: A real-life clinical data

Introduction

Partly due to its clinical heterogeneity, hidradenitis suppurativa (HS) is difficult to score accurately; illustrated by the large number of disease scores. In 2016, a systematic review by Ingram et al. reported the use of about thirty scores, and since then, this number has increased further. Our aim is twofold: to provide a succinct but detailed narrative review of the scores used to date, and to compare these scores with each other for individual patients.

Materials and methods

The review of the literature was done among articles in English and French, on Google, Google scholar, Pubmed, ScienceDirect and Cochrane. To illustrate the differences between scores, data from some Belgian patients included in the European Registry for HS were selected. A first series of patients compares the severity of the following scores: Hurley, Hurley Staging refined, three versions of Sartorius score (2003, 2007, 2009), Hidradenitis Suppurativa Physician Global Assessment (HS-PGA), International Hidradenitis Suppurativa Severity Scoring System (IHS4), Severity Assessment of Hidradenitis Suppurativa (SAHS), Hidradenitis Suppurativa Severity Index (HSSI), Acne Inversa Severity Index (AISI), the Static Metascore, and one score that is not specific to HS: Dermatology Life Quality Index (DLQI). A second set of patients illustrates how some scores change over time and with treatment: Hurley, Hurley Staging refined, Sartorius 2003, Sartorius 2007, HS-PGA, IHS4, SAHS, AISI, Hidradenitis Suppurativa Clinical Response (HiSCR), the very new iHS4-55, the Dynamic Metascore, and DLQI.

Results

Nineteen scores are detailed in this overview. We illustrate that for some patients, the scores do not predictably and consistently correlate with each other, either in an evaluation of the severity at a time-point t, or in the evaluation of the response to a treatment. Some patients in this cohort may be considered responders according to some scores, but non-responders according to others. The clinical heterogeneity of the disease, represented by its many phenotypes, seems partly to explain this difference.

Conclusion

These examples illustrate how the choice of a score can lead to different interpretations of the response to a treatment, or even potentially change the results of a randomized clinical trial.

Identification of Biomarkers and Critical Evaluation of Biomarker Validation in Hidradenitis Suppurativa: A Systematic Review

Importance

The identification and validation of biomarkers in hidradenitis suppurativa (HS) has potential to improve the understanding and management of this chronic, burdensome disease.

Objective

To systematically identify all known HS biomarkers, categorize them by biomarker type, and critically evaluate their validity according to established criteria.

Evidence Review

Eligibility criteria for this review (PROSPERO Registration 230830) included randomized clinical trials, uncontrolled clinical trials, cohort studies, case-control studies, and other observational studies with no restrictions of patient age, sex, race or ethnicity, or language of publication up until December 31, 2020. All articles were categorized into biomarker type, defined using the US Food and Drug Administration Biomarkers, Endpoints, and other Tools (BEST) glossary. Assessment of each identified biomarker was undertaken in line with the US Food and Drug Administration and European Medicines Agency guidelines for the validation of proposed biomarkers. Assessment of the strength of overall data regarding individual biomarkers was undertaken using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach.

Findings

A total of 3953 nonduplicate articles were screened, of which 1429 articles were retrieved based on the include/exclusion criteria applied. After full-text screen and data extraction, 106 articles were included in this review. The evidence of strength of 6 categories of biomarkers (susceptibility/risk, diagnostic, monitoring, predictive, prognostic, and pharmacodynamic/response biomarkers) was assessed using GRADE criteria. A total of 48 biomarkers were identified with a minimum GRADE rating of moderate. Only 1 diagnostic (serum IL-2R), 1 monitoring (dermal Doppler vascularity), and 2 predictive biomarkers (epithelialized tunnels and positive family history of HS) achieved a GRADE rating of high. None of the identified biomarkers had sufficient clinical validity to be recommended for routine use in the clinical setting.

Conclusions and Relevance

Major barriers to the identification, validation, and introduction of routine biomarkers in the management of HS include lack of independent biomarker validation studies (especially assumption-free "omics"-based techniques); insufficient assessment of collinearity between identified or proposed biomarkers; and a lack of routine integration of biomarkers into the structure of clinical trials. International consensus among researchers, clinicians, and pharmaceutical stakeholders is required to standardize goals and methods and encourage biomarker integration into future HS clinical trials. This systematic review presents a number of priorities for near-term future research to overcome such barriers and limitations of biomarkers in HS.