Clinical trials in children and adolescents with systemic lupus erythematosus: methodological aspects, regulatory landscape and future opportunities

Treatment patterns in paediatric and adult patients with SLE: a retrospective claims database study in the USA

OBJECTIVE

To assess real-world treatment regimens and patterns in childhood-onset SLE (cSLE) and adult-onset SLE (aSLE) cohorts, including similarities in treatments, duration of use and adherence.

METHODS

This retrospective study utilised data from Merative L.P. MarketScan Research Databases (USA). Index date was the date of first SLE diagnosis (2010-2019). Patients aged <18 years (cSLE) and ≥18 years (aSLE) at index date with confirmed SLE diagnosis and ≥12 months continuous enrolment during pre-index and post-index periods were included. The cohorts were stratified based on the presence (existing) or absence (new) of pre-index SLE. Primary outcomes (post-index period) included treatment regimens (all patients), and adherence (proportion of days covered (PDC)) and discontinuation of therapies initiated within 90 days of diagnosis (new patients). Univariate comparisons between cSLE and aSLE cohorts were performed using Wilcoxon rank-sum and χ² (or Fisher's exact) tests.

RESULTS

cSLE cohort included 1275 patients (mean age=14.1 years) and aSLE cohort included 66 326 patients (mean age=49.7 years). Antimalarials and glucocorticoids were commonly used among new (cSLE=64.4%/62.0%; aSLE=51.8%/49.7%) and existing (cSLE=68.6%/58.9%; aSLE=63.8%/51.3%) patients in both cohorts. Median oral glucocorticoid dose (prednisone equivalent) was higher in cSLE vs aSLE (new=22.1 vs 14.0 mg/day; existing=14.4 vs 12.3 mg/day; p<0.05). Mycophenolate mofetil use was higher in patients with cSLE vs aSLE (new=26.2% vs 5.8%; existing=37.6% vs 11.0%; p<0.0001). Compared with aSLE, more patients used combination therapies in cSLE (p<0.0001). Median PDC was higher in cSLE vs aSLE for antimalarials (0.9 vs 0.8; p<0.0001) and oral glucocorticoids (0.6 vs 0.3; p<0.0001). Treatment discontinuation was lower in cSLE vs aSLE for antimalarials (25.0% vs 33.1%; p<0.0001) and oral glucocorticoids (56.6% vs 71.2%; p<0.0001).

CONCLUSIONS

Management of cSLE and aSLE includes the same medication classes; differences include more intensive use of therapy in cSLE, warranting the need for approved safe medications for cSLE.

Extrapolation of Adult Efficacy Data to Pediatric Systemic Lupus Erythematosus: Evaluating Similarities in Exposure-Response

To streamline drug development, the United States Food and Drug Administration (FDA) can consider the extrapolation of adult efficacy data to children when the disease and drug effects are sufficiently similar. This study explored whether the relationship between drug exposure and response for selected drugs in systemic lupus erythematosus (SLE) was sufficiently similar to support a consideration of the extrapolation of adult efficacy data to children of ≥5 years of age. An exposure-response analysis of drugs used to treat SLE was conducted using published exposure versus response and efficacy versus time data. Statistical analyses included noncompartmental analysis of a drug's area under the effect curve and direct Imax pharmacodynamic (PD) modeling. Six drugs were included: azathioprine, belimumab, cyclophosphamide, hydroxychloroquine, mycophenolate/mycophenolic acid, and rituximab. For belimumab, the net change in responders at week 52 (the primary end point) was nearly identical between 1 adult trial and the pediatric trial. For mycophenolate, PD modeling suggested no significant differences in exposure and SLE disease activity between adults and children. For azathioprine, cyclophosphamide, hydroxychloroquine, and rituximab the data were not sufficient to quantitatively characterize the exposure-response relationship, but the clinical or pharmacologic response between children and adults was similar overall. Adult SLE data should be leveraged to guide pediatric drug development programs and identify areas with residual uncertainty regarding the effectiveness or safety of a drug in children. The degree to which efficacy extrapolation can reduce clinical trial requirements in pediatric SLE should be individualized for each new drug product, depending in part on the mechanism of action of the drug and the similarity of disease manifestations in children and adults.

An artificial neural network model based on autophagy-related genes in childhood systemic lupus erythematosus

Background

Childhood systemic lupus erythematosus (cSLE) is a multisystemic, life-threatening autoimmune disease. Compared to adults, SLE in childhood is more active, can cause multisystem involvement including renal, neurological and hematological, and can cause cumulative damage across systems more rapidly. Autophagy, one of the core functions of cells, is involved in almost every process of the immune response and has been shown to be associated with many autoimmune diseases, being a key factor in the interplay between innate and adaptive immunity. Autophagy influences the onset, progression and severity of SLE. This paper identifies new biomarkers for the diagnosis and treatment of childhood SLE based on an artificial neural network of autophagy-related genes.

Methods

We downloaded dataset GSE100163 from the Gene Expression Omnibus database and used Protein–protein Interaction Network (PPI) and Least Absolute Shrinkage and Selection Operator (LASSO) to screen the signature genes of autophagy-related genes in cSLE. A new artificial neural network model for cSLE diagnosis was constructed using the signature genes. The predictive efficiency of the model was also validated using the dataset GSE65391. Finally, "CIBERSORT" was used to calculate the infiltration of immune cells in cSLE and to analyze the relationship between the signature genes and the infiltration of immune cells.

Results

We identified 37 autophagy-related genes that differed in cSLE and normal samples, and finally obtained the seven most relevant signature genes for cSLE (DDIT3, GNB2L1, CTSD, HSPA8, ULK1, DNAJB1, CANX) by PPI and LASOO regression screening, and constructed an artificial neural network diagnostic model for cSLE. Using this model, we plotted the ROC curves for the training and validation group diagnoses with the area under the curve of 0.976 and 0.783, respectively. Finally, we performed immunoassays on cSLE samples, and the results showed that Plasma cells, Macrophages M0, Dendritic cells activated and Neutrophils were significantly infiltrated in cSLE.

Conclusion

We constructed an artificial neural network diagnostic model of seven autophagy-related genes that can be used for the diagnosis of cSLE. Meanwhile, the characteristic genes affect the immune infiltration of cSLE, which may provide new perspectives for the exploration of cSLE treatment and related mechanisms.

Identify differential inflammatory cellular and serology pathways between children and adult patients in the lupus registry

BACKGROUND

Age variances in systemic lupus erythematosus (SLE) may reflect different patterns and consequences. Monocyte differentiation is critical, and cytokine and chemokine milieu may be associated with long term outcome and treatment responses. This study aims to evaluate the inflammatory cellular and serology pathways associated with age in our lupus registry.

METHODS

We included patients with SLE and divided them into 2 groups according to age, ≤18 or >18 years old. We performed flow cytometry analysis to define the peripheral blood monocyte differentiation pattern and phenotypes and used the multiplex method to detect cytokine and chemokine panels. The results were then compared between the 2 subgroups.

RESULTS

In total, 47 SLE patients were included in this study. Of those, 23 patients were 18 years old or younger, and 24 patients were over the age of 18 years old. An increased distribution of circulating Type 2b macrophage (M2b) subsets was found in patients over 18 years old (P < 0.01), and we found the Type 1 macrophage (M1) to demonstrate a marked increase in those patients ≤18 years old (P = .05). Eotaxin values were significantly higher in patients >18 years old (P = .03), and Macrophage Inflammatory Protein (MIP)-1alpha, MIP-1beta, Interleukine (IL)-1Ra, Interferon (IFN)-alpha2, IL-12, IL-13, IL-17A, IL-1beta, IL-2, IL-4, IL-5, IL-7, IL-9, Monocyte Chemoattractant Protein (MCP)-3, Transforming Growth Factor (TGF)-alpha, and Tumor necrosis factor (TNF)-beta were significantly higher in patients ≤18 years old (all P < .05).

CONCLUSIONS

We found significant M2b polarization in adult SLE patients, and several cytokines and chemokines were significantly higher in SLE patients ≤ 18 years old. Peripheral blood mononuclear cell differentiation and cytokine milieu could represent composite harm from both Type 2 helper T cells (Th2) and Type 17 helper T cells (Th17) pathways and may thus be a potential therapeutic target in younger SLE patients.

Use of EuroLupus Cyclophosphamide Dosing for the Treatment of Lupus Nephritis in Childhood-onset Systemic Lupus Erythematosus in North America

OBJECTIVE

Childhood-onset systemic lupus erythematosus (cSLE) has higher rates of lupus nephritis (LN) than adult-onset SLE, often requiring intensive immunosuppression. This study examined North American practices and preferences for the low-dose EuroLupus cyclophosphamide (CYC) protocol, as compared to the high-dose National Institutes of Health (NIH) CYC protocol, to treat LN in cSLE.

METHODS

A 35-item Web-based survey was distributed to Childhood Arthritis and Rheumatology Research Alliance (CARRA) and Pediatric Nephrology Research Consortium (PNRC) providers. The survey assessed participant demographics, CYC prescribing practices, perceptions of EuroLupus protocol, and LN vignette treatment decisions; 1 vignette was taken from a 2009 CARRA survey and responses were compared. Multivariable logistic regression analyzed provider factors associated with use of low- vs high-dose CYC.

RESULTS

Responses were provided by 185/421 (44%) pediatric rheumatologists (CARRA) and 40/354 (11%) pediatric nephrologists (PNRC). Among respondents who prescribed CYC for pediatric LN over the past year (n = 135), half reported using EuroLupus. When presented with the same vignette about an adolescent with class IV LN, 32% of pediatric rheumatologists chose EuroLupus dosing in 2020, vs 6% in 2009. Provider factors associated with choosing the low-dose regimen were familiarity with the protocol (OR 4.2, P = 0.006) and greater perceived benefit (OR 1.6, P < 0.0001). Pediatric nephrologists had similar responses to the pediatric rheumatology providers. Overall, 78% of respondents perceived EuroLupus protocol efficacy to be equivalent to the high-dose protocol in cSLE LN.

CONCLUSION

Pediatric specialists are currently more likely to use low-dose CYC to treat cSLE LN than they were a decade ago. Nevertheless, familiarity with EuroLupus dosing remains low.

"There's so much to be done": a qualitative study to elucidate research priorities in childhood-onset systemic lupus erythematosus

Objective

There is a pressing need for high-quality, comprehensive research to describe the natural history, best treatments, access to care and disparities in care for patients with childhood-onset SLE (cSLE). Building on a previously published survey study of cSLE clinicians and researchers to describe research priorities in cSLE, the primary objective of this study was to conduct expert interviews to define high-priority areas for cSLE research.

Methods

Individuals with identified multidisciplinary expertise in cSLE were recruited worldwide using purposive sampling technique. Experts participated in open-ended, semistructured qualitative interviews. Interviews were designed to elicit expert perspectives on research priorities, optimal research approaches, and factors that facilitate and hinder advancing cSLE research. Interviews were digitally recorded, transcribed and de-identified for analysis. Analysis for underlying themes of cSLE expert perspectives was performed using a constant comparative approach.

Results

Twenty-nine experts with diverse clinical and research backgrounds participated. Themes emerged within five domains: (1) expanding disease knowledge; (2) investigator collaboration; (3) partnering with patients and families; (4) improving care to optimise research; and (5) overcoming investigator barriers. Choosing a singular area of focus was difficult; experts identified many competing priorities. Despite the numerous priorities that emerged, experts described several existing and potential opportunities for advancing cSLE research.

Conclusions

In addition to the priorities identified by cSLE experts in this study, the opportunities for advancing cSLE research and care that were proposed should be used as a foundation for creation of a cSLE research agenda for both research and funding allocation.

An Update on the Management of Childhood-Onset Systemic Lupus Erythematosus

Childhood-onset systemic lupus erythematosus (cSLE) is a prototype of a multisystemic, inflammatory, heterogeneous autoimmune condition. This disease is characterized by simultaneous or sequential organ and system involvement, with unpredictable flare and high levels of morbidity and mortality. Racial/ethnic background, socioeconomic status, cost of medications, difficulty accessing health care, and poor adherence seem to impact lupus outcomes and treatment response. In this article, the management of cSLE patients is updated. Regarding pathogenesis, a number of potential targets for drugs have been studied. However, most treatments in pediatric patients are off-label drugs with recommendations based on inadequately powered studies, therapeutic consensus guidelines, or case series. Management practices for cSLE patients include evaluations of disease activity and cumulative damage scores, routine non-live vaccinations, physical activity, and addressing mental health issues. Antimalarials and glucocorticoids are still the most common drugs used to treat cSLE, and hydroxychloroquine is recommended for nearly all cSLE patients. Disease-modifying antirheumatic drugs (DMARDs) should be standardized for each patient, based on disease flare and cSLE severity. Mycophenolate mofetil or intravenous cyclophosphamide is suggested as induction therapy for lupus nephritis classes III and IV. Calcineurin inhibitors (cyclosporine, tacrolimus, voclosporin) appear to be another good option for cSLE patients with lupus nephritis. Regarding B-cell-targeting biologic agents, rituximab may be used for refractory lupus nephritis patients in combination with another DMARD, and belimumab was recently approved by the US Food and Drug Administration for cSLE treatment in children aged > 5 years. New therapies targeting CD20, such as atacicept and telitacicept, seem to be promising drugs for SLE patients. Anti-interferon therapies (sifalimumab and anifrolumab) have shown beneficial results in phase II randomized control trials in adult SLE patients, as have some Janus kinase inhibitors, and these could be alternative treatments for pediatric patients with severe interferon-mediated inflammatory disease in the future. In addition, strict control of proteinuria and blood pressure is required in cSLE, especially with angiotensin-converting enzyme inhibitor and angiotensin receptor blocker use.

Prerequisites to support high-quality clinical trials in children and young people

Children have the right to treatment based on the same quality of information that guides treatment in adults. Without the proper evaluation of medicinal products and devices in paediatric clinical trials that are designed to meet the rigorous standards of the competent authorities, children are discriminated from advances in medicine. There are regulatory, scientific and ethical incentives to address the knowledge gap regarding efficacy and safety of medicines in the paediatric population. High-quality clinical trials involving children of all ages can generate data that will ultimately close the knowledge gaps and support decision making.For clinical trials that enrol children, the needs are specialised and often resource intensive. Prerequisites for successful paediatric clinical trials are personnel with training in both paediatrics and neonatology and expertise in clinical trials in these populations. Moreover, national and international networks for efficient collaboration, dissemination of information, and sharing of resources and expertise are also needed, together with competent, efficient and high-quality local infrastructure with effective processes. Monitoring and oversight bodies with the relevant competence, including expertise in paediatrics, is also an important prerequisite for paediatric clinical trials. Compromise in any of these components will compromise the downstream results.This paper discusses the structures and competences needed in order to perform effective, high-quality paediatric clinical trials with the ultimate goal of better medicines and treatments for children. We propose a model of examining the process as a series of components that each has to be optimised, then all the components are actively optimised to function together as an ecosystem, and the resulting ecosystem functions well with the general research system and the healthcare delivery system.

Outcome Scores in Pediatric Rheumatology

PURPOSE OF REVIEW

Providing a summary of the latest research on outcome measures in juvenile idiopathic arthritis, childhood -onset systemic lupus erythematosus, and juvenile dermatomyositis.

RECENT FINDINGS

A rational management of patients with pediatric rheumatic diseases requires the regular assessment of the level of disease activity and damage, as well as the evaluation of therapeutic response through validated and standardized outcome measures. Ideally, such tools should be simple, feasible, and easily applicable in routine care. Recently, there has been a great deal of effort to refine existing tools and devise novel outcome measures, aiming to address the various aspects of disease impact and to improve the reliability of research studies and clinical trials. The newest outcome tools in pediatric rheumatology have markedly enlarged the spectrum of health domains assessable in a standardized way, thus increasing the reliability of evaluation of clinical response and fostering future clinical trials.

Update on the treatment and outcome of systemic lupus erythematous in children

PURPOSE OF REVIEW

Provide an update of studies published in last 2 years on the outcomes and therapies in childhood-onset systemic lupus erythematous (cSLE).

RECENT FINDINGS

Additional evidence has been provided about the benefits of universal hydroxychloroquine in SLE patients, although antimalarial maculopathy may be more prevalent than previously thought. Recent studies support lower glucocorticoid doses than used in the past may provide comparable therapeutic benefits, and cSLE patients can mount adequate immunogenic response and sustain long-term seroprotective titers when vaccinated. Long-term studies of adults with cSLE confirmed that damage accrual increases with disease duration. Cardiovascular disease, renal transplants, replacement arthroplasties, and myocardial infarctions occur between 20 and 40 years of age. Higher prednisone doses predicted higher damage trajectory and antimalarial exposure was protective. There were no prospective clinical trials published in pediatric patients with cSLE, but positive results from phase II trials with bariticinib and ustekinumab in adult SLE may raise the expectation that these drugs could be beneficial when used in cSLE.

SUMMARY

The dire need for more clinical trials and licensed medications for cSLE persist as well as decreasing damage accrual.

A systematic review of pharmacological therapies and their effectiveness on health-related quality of life outcomes in patients with juvenile-onset systemic lupus erythematosus

Juvenile-onset systemic lupus erythematosus (JSLE) presents with an aggressive course and high morbidity associated with disease and treatment. JSLE patients have a poorer health-related quality of life (HRQoL) when compared with age-matched patients with other rheumatologic disorders. We aim to summarize the impact of current pharmacological therapies on the HRQoL of JSLE patients. Search strategies were developed across seven databases. Randomized clinical trials (RCTs) and cohort studies comparing interventions to standard therapy, placebo or pre-post cohort comparisons for more than 4 weeks were included. The outcome included self-reported scales compared at baseline and a therapeutic time point. Risk of bias was evaluated by using the Cochrane risk of bias tool and the Newcastle-Ottawa quality assessment scale. A total of 2812 articles were narrowed down to 309 for full-text screening. Four RCTs and one prospective cohort study, with a total of 634 JSLE patients, met the inclusion criteria. Four of the studies had a controlled intervention plus standard therapy compared with standard therapy alone or placebo. Multiple indices were used to evaluate HRQoL. These included the Pediatric Quality of Life Inventory, Childhood Health Assessment Questionnaire, Simple Measure of Impact of Lupus Erythematosus in Youngsters tool, Kids Fatigue Severity Scale and Child Depression Inventory. A single study reported a significant improvement while remaining studies reported no difference or failed to report the statistical analysis. Although HRQoL is significantly impaired in JSLE, evidence regarding its improvement is limited due to the small number of eligible studies, heterogeneity in scales, and HRQoL domains. A universal HRQoL questionnaire for JSLE needs to be established and used in both the research and clinical setting. All studies should adhere to reporting guidelines.