Evaluating change in disease activity needed to reflect meaningful improvement in quality of life for clinical trials in cutaneous lupus erythematosus

An update on clinical trials for cutaneous lupus erythematosus

Cutaneous lupus erythematosus (CLE) comprises dermatologic manifestations that may occur independently or with systemic lupus erythematosus (SLE). Despite advancements in refining CLE classification, establishing precise subtype criteria remains challenging due to overlapping presentations and difficulty in distinguishing morphology. Current treatments encompass preventive measures, topical therapies, and systemic approaches. Hydroxychloroquine and glucocorticoids are the sole US Food and Drug Administration (FDA)-approved medications for CLE, with numerous off-label treatments available. However, these treatments are often not covered by insurance, imposing a significant financial burden on patients. The exclusion of most CLE patients, particularly those without concurrent SLE, from trials designed for SLE has resulted in a lack of targeted treatments for CLE. To develop effective CLE treatments, validated outcome measures for tracking patient responsiveness are essential. The Cutaneous Lupus Erythematosus Disease Area and Severity Index is widely utilized for its reliability, validity, and ability to differentiate between skin activity and damage. In contrast, the FDA mandates the use of the Investigator's Global Assessment, a five-point Likert scale related to lesion characteristics, for skin-related therapeutic trials. It requires the disease to resolve or almost completely resolve to demonstrate improvement, which can be difficult when there is residual erythema or incomplete clearance that is meaningfully improved from a patient perspective. Various classes of skin lupus medications target diverse pathways, allowing tailored treatment based on the patient's lupus inflammatory profile, resulting in improved outcomes. Promising targeted therapeutic drugs include anifrolumab (anti-type 1 interferon), deucravacitinib (allosteric tyrosine kinase 2 inhibitor), litifilimab (plasmacytoid dendritic cell-directed therapy), iberdomide (cereblon-targeting ligand), and belimumab (B-cell directed therapy). Despite the significant impact of CLE on quality of life, therapeutic options remain inadequate. While promising treatments for cutaneous lupus are emerging, it is crucial to underscore the urgency for skin-focused treatment outcomes and the implementation of validated measures to assess therapeutic effectiveness in clinical trials.

Clinical trial outcomes for SLE: what we have and what we need

The paradigm of drug approval in SLE currently relies on successful large phase III randomised controlled trials and a set of primary, secondary and additional end points. Taken together, these outcomes offer a nuanced understanding of the efficacy and safety of the investigational agent. In this review, we thoroughly examine the main outcomes used in SLE trials and highlight unmet requirements as well as potential venues for future trial design in SLE. Disease activity indices can be broadly categorised into global-specific and organ-specific indices, in particular for skin, joints and kidneys, but there is no universal consensus about their use in clinical trials. Because each of these instruments has its own intrinsic strengths and weaknesses, the assessment of treatment response has progressed from relying solely on one individual disease activity index to using composite responder definitions. Those are typically measured from the trial baseline to the end point assessment date and may be combined with the need to taper and maintain glucocorticoids (GCs) within prespecified ranges. Remission and low disease activity are two critical states in the perspective of 'Treat-to-Target' trials, but are not fully recognised by regulators. While significant progress has been made in clinical trial outcomes for SLE, there is a clear need for continued innovation. Addressing these challenges will require collaboration between researchers, clinicians, patients as well as with regulatory agencies to refine existing outcome measures, incorporate meaningful and ethnically diverse patient perspectives, foster relevant digital opportunities and explore new therapeutic avenues, including early use of investigational agents. By doing so, we can advance our ability to manage SLE effectively and safely and improve the lives of those living with this complex and impactful autoimmune disease.

Emerging immunotherapeutic strategies for cutaneous lupus erythematosus: an overview of recent phase 2 and 3 clinical trials

INTRODUCTION

Cutaneous lupus erythematosus (CLE) is an autoimmune disease that is clinically heterogenous and may occur with or without the presence of systemic lupus erythematosus (SLE). While existing on a spectrum, CLE and SLE present differences in their underlying pathogenesis and therapeutic responses. No new therapies have been approved in recent decades by the U.S. Food and Drug Administration for CLE, although frequently refractory to conventional therapies. There is an unmet need to develop effective drugs for CLE as it significantly impacts patients' quality of life and may leave irreversible disfiguring damage.

AREAS COVERED

This review provides an update on the latest phase 2 and 3 clinical trials performed in CLE or SLE using skin-specific outcome measures. Emergent therapies are presented alongside their mechanism of action as recent translational studies have permitted identification of critical targets among immune cells and/or pathways involved in CLE.

EXPERT OPINION

While the recent literature has few trials for CLE, drugs targeting type I interferon, its downstream signaling and plasmacytoid dendritic cells have shown promising results. Further research is required to develop long-awaited effective therapies, and this review highlights the importance of implementing trials dedicated to CLE to fill the current gap in CLE therapeutics.

Litifilimab (BIIB059), a promising investigational drug for cutaneous lupus erythematosus

INTRODUCTION

There are no U.S. Food and Drug Administration (FDA) approved therapies for cutaneous lupus erythematosus (CLE). Litifilimab is a monoclonal antibody against BDCA2, a plasmacytoid dendritic cell specific antigen, currently under investigation for systemic lupus erythematosus (SLE) and CLE. The LILAC study, published in the New England Journal of Medicine, is a phase II randomized controlled trial for CLE which demonstrated superiority of Litifilimab over placebo using a skin directed outcome measure.

AREAS COVERED

This review identifies challenges that have hindered the development of any approved treatments for CLE, recent SLE trials that include skin disease data, and the pharmacological properties of litifilimab. We review the clinical efficacy and safety of litifilimab for both SLE and CLE in the phase I and II clinical trials. This review aims to highlight the need for more CLE specific clinical trials and examine the potential of litifilimab as the first FDA approved therapy for CLE. (Clinical trial registration: www.clinicaltrials.gov identifier is NCT02847598.).

EXPERT OPINION

Litifilimab demonstrated efficacy in a randomized phase II clinical trial as a standalone CLE trial using validated skin specific outcome measures, making it the first successful clinical trial for a CLE targeted therapy. If approved, litifilimab will be a pivotal change in the landscape of CLE management especially for severe and refractory disease.

Meeting report: the ALPHA project: a stakeholder meeting on lupus clinical trial outcome measures and the patient perspective

Drug development in lupus has improved over the past 10 years but still lags behind that of other rheumatic disease areas. Assessment of prospective lupus therapies in clinical trials has proved challenging for reasons that are multifactorial including the heterogeneity of the disease, study design limitations and a lack of validated biomarkers which greatly impacts regulatory decision-making. Moreover, most composite outcome measures currently used in trials do not include patient-reported outcomes. Given these factors, the Addressing Lupus Pillars for Health Advancement Global Advisory Committee members who serve on the drug development team identified an opportunity to convene a meeting to facilitate information sharing on completed and existing outcome measure development efforts. This meeting report highlights information presented during the meeting as well as a discussion on how the lupus community may work together with regulatory agencies to simplify and standardise outcome measures to accelerate development of lupus therapeutics.

Trial of Anti-BDCA2 Antibody Litifilimab for Systemic Lupus Erythematosus

BACKGROUND

Antibody-binding of blood dendritic cell antigen 2 (BDCA2), which is expressed exclusively on plasmacytoid dendritic cells, suppresses the production of type I interferon that is involved in the pathogenesis of systemic lupus erythematosus (SLE). The safety and efficacy of subcutaneous litifilimab, a humanized monoclonal antibody that binds to BDCA2, in patients with SLE have not been extensively studied.

METHODS

We conducted a phase 2 trial of litifilimab involving participants with SLE. The initial trial design called for randomly assigning participants to receive litifilimab (at a dose of 50, 150, or 450 mg) or placebo administered subcutaneously at weeks 0, 2, 4, 8, 12, 16, and 20, with the primary end point of evaluating cutaneous lupus activity. The trial design was subsequently modified; adults with SLE, arthritis, and active skin disease were randomly assigned to receive either litifilimab at a dose of 450 mg or placebo. The revised primary end point was the change from baseline in the total number of active joints (defined as the sum of the swollen joints and the tender joints) at week 24. Secondary end points were changes in cutaneous and global disease activity. Safety was also assessed.

RESULTS

A total of 334 adults were assessed for eligibility, and 132 underwent randomization (64 were assigned to receive 450-mg litifilimab, 6 to receive 150-mg litifilimab, 6 to receive 50-mg litifilimab, and 56 to receive placebo). The primary analysis was conducted in the 102 participants who had received 450-mg litifilimab or placebo and had at least four tender and at least four swollen joints. The mean (±SD) baseline number of active joints was 19.0±8.4 in the litifilimab group and 21.6±8.5 in the placebo group. The least-squares mean (±SE) change from baseline to week 24 in the total number of active joints was -15.0±1.2 with litifilimab and -11.6±1.3 with placebo (mean difference, -3.4; 95% confidence interval, -6.7 to -0.2; P = 0.04). Most of the secondary end points did not support the results of the analysis of the primary end point. Receipt of litifilimab was associated with adverse events, including two cases of herpes zoster and one case of herpes keratitis.

CONCLUSIONS

In a phase 2 trial involving participants with SLE, litifilimab was associated with a greater reduction from baseline in the number of swollen and tender joints than placebo over a period of 24 weeks. Longer and larger trials are required to determine the safety and efficacy of litifilimab for the treatment of SLE. (Funded by Biogen; LILAC ClinicalTrials.gov number, NCT02847598.).

The Meaning and Reliability of Minimal Important Differences (MIDs) for Clinician-Reported Outcome Measures (ClinROMs) in Dermatology-A Scoping Review

Background: Clinician-reported outcome measures (ClinROMs) are frequently used in clinical trials and daily practice to evaluate the disease status and evolution of skin disorders. The minimal important difference (MID) represents the smallest difference that decreases the disease impact enough to make a treatment change worthwhile for patients. As no clear guidance exists on the preferred method to calculate MIDs for ClinROMs, we evaluated how the published values for different skin disorders should be interpreted. Methods: A systematic search was performed for MIDs of ClinROMs that focus on skin disorders and/or symptoms. The results of the questions in the credibility instrument for MIDs of Devji et al., 2020 were analyzed to gain insights into the meaning of these MIDs. Results: 29 MIDs were identified. The most common skin diseases were atopic dermatitis/eczema, followed by bullous disorders and psoriasis. A minimal important difference from the patients’ perspective was determined in 31% of the cases. However, in 41.4% of the cases, it concerned a substantial rather than a minimal difference in disease severity rated by physicians. Over half (55.1%) of the studies contained an inadequate number of patients (n < 150). MID values increased substantially in patients with severe compared to mild disease. Conclusions: MIDs of ClinROMs for skin disorders should be carefully interpreted due to the substantial differences in methodology between the studies. There is an urgent need for a consensus method to report reliable MIDs. Otherwise, this lack of uniformity could not only affect the design and conclusion of clinical trials but also skew treatment decisions.

Development of a working core outcome set for cutaneous lupus erythematosus: a practical approach to an urgent unmet need

Objective

The lack of standardised outcomes and outcome measures for cutaneous lupus erythematosus (CLE) represents a substantial barrier to clinical trial design, comparative analysis and approval of novel investigative treatments. We aimed to develop a working core outcome set (COS) for CLE randomised controlled trials and longitudinal observational studies.

Methods

We conducted a multistage literature review of CLE and SLE studies to generate candidate domains and outcome measures. Domains were narrowed to a working core domain set. Outcome measures for core domains were identified and examined.

Results

Proposed core domains include skin-specific disease activity and damage, investigator global assessment (IGA) of disease activity, symptoms (encompassing itch, pain and photosensitivity), health-related quality of life (HRQoL) and patient global assessment (PtGA) of disease activity. Recommended physician-reported outcome measures include the Cutaneous Lupus Erythematous Disease Area and Severity Index (CLASI) and Cutaneous Lupus Activity IGA (CLA-IGA). For the domains of symptoms, HRQoL and PtGA of disease activity, we were unable to recommend one clearly superior instrument.

Conclusion

This work represents a starting point for further refinement pending formal consensus activities and more rigorous evaluations of outcome measure quality. In the interim, the proposed working COS can serve as a much-needed guide for upcoming CLE clinical trials.

Cutaneous Lupus Erythematosus and Dermatomyositis: Utilizing Assessment Tools for Treatment Efficacy

There have been important developments in defining cutaneous lupus erythematosus and dermatomyositis. The skin manifestations of these two diseases have a profound impact on QOL, with both emotional and symptomatic impacts that are important to address. The proliferation of potential therapeutic targets has made it important to make sure that these diseases are defined in a way that they can be included in translational and clinical studies of both localized and systemic forms of the diseases. There are now validated disease tools and QOL studies that are facilitating current and future scientific and therapeutic developments.

Measurement of specific organ domains in lupus randomised controlled trials: a scoping review

OBJECTIVE

Randomised controlled trials (RCTs) in systemic lupus erythematosus (SLE, lupus) typically adopt composite responder definitions as primary efficacy endpoints, however outcomes within individual organ domains are also important to understand. The aim of this scoping review was to evaluate how organ-specific disease activity and therapeutic responses have been measured and reported in lupus RCTs.

METHODS

We searched MEDLINE, EMBASE, Cochrane registry and clinicaltrials.gov. Eligible studies were RCTs investigating efficacy of an immune-directed drug therapy in active SLE, published January 2000-March 2021, excluding studies limited to lupus nephritis. Data were extracted independently in duplicate into a template and summarised descriptively.

RESULTS

Thirty-four RCTs were included, of which 32 (94%) reported activity and/or responses in at least one organ domain. Study populations had a high, although variable, frequency of baseline musculoskeletal and mucocutaneous activity and low but also variable representation of other domains. Definitions of organ-specific responses were inconsistent, even within individual instruments. Response in most organ domains were evaluated using BILAG and SLEDAI components but meaningful comparison between treatment arms was limited by small subgroups analysed in a post hoc fashion. Specific mucocutaneous and arthritis instruments were also used, including within pre-specified organ-specific endpoints, which discriminated between treatment arms in some studies.

CONCLUSION

Mucocutaneous and musculoskeletal manifestations predominate in SLE RCTs. Organ-specific outcome measures are commonly reported, but definitions of involvement and response are inconsistent. Research into the development of new outcome measures for key organ domains, and validation and comparison of response definitions using existing instruments, is needed.

Filgotinib or Lanraplenib in Moderate to Severe Cutaneous Lupus Erythematosus: A Phase 2, Randomised, Double-Blind, Placebo-Controlled Study

OBJECTIVES

To explore the safety and efficacy of filgotinib (FIL), a Janus kinase 1 inhibitor, and lanraplenib (LANRA), a spleen kinase inhibitor in cutaneous lupus erythematosus (CLE).

METHODS

This was a phase 2, randomised, double-blind, placebo-controlled, exploratory, proof-of-concept study of LANRA (30 mg), FIL (200 mg), or placebo (PBO) once daily for 12 weeks in patients with active CLE. At week 12, PBO patients were rerandomised 1:1 to receive LANRA or FIL for up to 36 additional weeks.

RESULTS

Of 47 randomised patients, 45 were treated (N = 9 PBO, N = 19 LANRA, N = 17 FIL). The primary end point (change from baseline in Cutaneous Lupus Erythematosus Disease Area and Severity Index Activity [CLASI-A] score at week 12) was not met. Least squares mean (standard error) CLASI-A score change from baseline was -5.5 (2.56) with PBO, -4.5 (1.91) with LANRA, and -8.7 (1.85) with FIL. Numerical differences between FIL and PBO were greater in select subgroups. A ≥ 5-point improvement in CLASI-A score at week 12 was achieved by 50.0%, 56.3%, and 68.8% in the PBO, LANRA, and FIL arms, respectively. A numerically greater proportion of patients in the FIL arm (50%) also achieved ≥50% improvement in CLASI-A score at week 12 (37.5% PBO, 31.3% LANRA). Most adverse events (AEs) were mild or moderate in severity. Two serious AEs were reported with LANRA and 1 with FIL.

CONCLUSION

The primary end point was not met. Select subgroups displayed a numerically greater treatment response to FIL relative to PBO. LANRA and FIL were generally well tolerated.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03134222.

The CLASI, a validated tool for the evaluation of skin disease in lupus erythematosus: a narrative review

Cutaneous lupus erythematosus (CLE) can present with or without features of systemic lupus erythematosus (SLE), with estimates of the incidence of isolated skin disease almost equaling the incidence of those with systemic disease. However, despite the impact CLE has on a patient’s quality of life (QoL), there has been no US Food and Drug Administration (FDA) approved treatment for the disease in the past 50 years. In addition, patients with skin predominant LE are often excluded from clinical SLE trials. In the rare trials that include patients with skin predominant LE, disease activity and progression in the skin are often difficult to evaluate using multi-organ outcome measures. The need for new therapies for CLE and the lack of focus on skin outcomes has led to the development of the Cutaneous Lupus Disease Area and Severity Index (CLASI), a validated organ-specific outcome measure that is not only responsive to change in disease activity and damage but also correlated to changes in a patient’s QoL. This paper will emphasize the extensive validation studies performed in developing the CLASI, as well as the importance of clinical trials using the CLASI to address the need for improved therapies for patients with lupus skin manifestations.