Assessing residual inflammation and macrophage presence in lupus nephritis after 3 months of intensified treatment with prednisolone, mycofenolate mofetil and voclosporin as compared to mycofenolate mofetil and prednisolone: an open label randomized controlled trial (MAPLE study)

The primary objective of this study is to establish that rapidly induced immunological remission on a cellular and histopathological level in lupus nephritis patients (class III/IV+/-V) can be attained with the addition of the calcineurin inhibitor voclosporin on top of mycophenolate mofetil and prednisolone, compared to mycophenolate mofetil and prednisolone alone. This is clinically relevant as achieving early immunological remission may improve long-term renal outcomes and prevent progression of kidney damage in lupus nephritis. Specifically, the primary objective encompasses: determining differences in macrophage clusters in kidney tissue between treatment arms; assessing histological response of the intensified treatment regimen compared to standard therapy; and evaluating whether early histological response is associated with clinical remission after two years, including identification of innovative early response determinants such as circulating monocyte phenotyping.

The secondary objectives include: assessing the phenotype of circulating monocytes in lupus nephritis patients compared to systemic lupus erythematosus patients without nephritis and healthy subjects, with association to clinical and biochemical parameters and single-cell RNA sequencing data, specifically identifying differences in peripheral monocyte phenotype; and identifying potential biomarkers of disease activity in single-cell RNA sequencing data for validation in urine and/or serum, with the aim of potentially rendering kidney biopsy obsolete through identification of serum and/or urinary biomarkers.

The sponsor does not provide information regarding the total number of participants. The trial population consists of three distinct groups: patients with **lupus nephritis**, patients with **systemic lupus erythematosus** (SLE) serving as a disease control group, and healthy subjects serving as a control group. The lupus nephritis group includes individuals aged 16 to 70 years with either de novo or flaring SLE according to the EULAR/ACR criteria and suspected class III or IV lupus nephritis with a clinical indication for **kidney biopsy**. Eligible lupus nephritis participants must have an **estimated glomerular filtration rate** (eGFR) measured by **cystatin C** of greater than 20 mL/min. The SLE disease control group comprises patients aged 16 to 70 years diagnosed with SLE according to EULAR/ACR guidelines. The healthy control group consists of individuals aged 16 to 70 years with a blank medical history, with a majority (75%) being female subjects. Both male and female participants are included across all study groups. No vulnerable populations are selected for this trial.

This clinical trial is designed as an **open-label randomized controlled trial** evaluating the treatment of **lupus nephritis** class III or IV in patients with **systemic lupus erythematosus**. The study compares intensified immunosuppressive therapy consisting of **voclosporin** in combination with **mycophenolate mofetil** and **prednisolone** (arm 1) against standard treatment with mycophenolate mofetil and prednisolone alone (arm 2). The trial is classified as a **low-intervention clinical trial** and is conducted as a **phase IV** post-authorization study. The primary objective is to establish whether rapidly induced immunological remission at the cellular and histopathological level can be achieved with the addition of the **calcineurin inhibitor** voclosporin. The trial employs advanced methodologies including **single-cell RNA sequencing** and spatial transcriptomics to determine differences in **macrophage** clusters in kidney tissue between treatment arms and to distinguish residential macrophages from monocyte-derived macrophages.

The trial includes three participant groups: patients with de novo or flaring lupus nephritis requiring **kidney biopsy**, patients with systemic lupus erythematosus without nephritis serving as disease controls, and healthy subjects as controls. Principal inclusion criteria for lupus nephritis patients include diagnosis according to **EULAR/ACR criteria**, suspicion of class III or IV disease with clinical indication for biopsy, age between 16 and 70 years, and **estimated glomerular filtration rate** measured by **cystatin C** greater than 20 mL/min. The maximum daily dose of voclosporin is 48 mg administered via the **oral route** as soft capsules, with a maximum treatment period of 36 months. The study is estimated to commence recruitment in January 2026 with an anticipated completion date of January 2030.

Participants undergo a screening visit with baseline kidney biopsy at enrollment, followed by a repeat kidney biopsy at 3 months of treatment to assess histological and cellular response. Sequential study visits are conducted to monitor clinical parameters including **proteinuria** levels, renal function, and safety assessments. Additional blood samples are collected during routine clinical blood draws for peripheral **monocyte** phenotyping using bulk RNA sequencing and **flow cytometry**. Urine and serum samples are stored sequentially for biomarker identification. The follow-up period extends to two years to assess clinical remission and correlate early histological response with long-term outcomes. The total duration of participant involvement varies depending on treatment response and clinical course, with extended monitoring up to the maximum treatment period.

Conditions that may lead to early termination from the study include:

• Significant deterioration in renal function or disease progression requiring alternative therapeutic intervention

• Development of unacceptable **adverse events** or safety concerns related to study medication

• Participant withdrawal of consent

• Non-compliance with study procedures or treatment regimen

• Investigator determination that continued participation is not in the participant's best interest

The end-of-study visit includes final clinical and laboratory assessments to evaluate treatment outcomes and long-term safety. Immunohistochemical confirmation of macrophage markers identified through single-cell RNA sequencing is performed to assess spatial distribution in **glomerular** versus **interstitial** compartments and to evaluate their predictive and prognostic utility. The study aims to identify reliable serum and urinary biomarkers that reflect tissue damage and treatment response, with the long-term goal of potentially reducing the need for repeat kidney biopsies in lupus nephritis management.

The experimental treatment consists of **voclosporin** administered as **Lupkynis 7.9 mg soft capsules**. The active substance voclosporin is a **calcineurin inhibitor** of chemical origin. The **pharmaceutical form** is soft capsules, with each capsule containing 7.9 mg of voclosporin. The **route of administration** is oral. The **maximum daily dose** is 48 mg, which corresponds to a **maximum total daily dose** of 48 mg. The **maximum treatment period** is 36 months. Voclosporin is classified under **ATC code L04AD03** and is authorized by OTSUKA PHARMACEUTICAL NETHERLANDS B.V. under the **marketing authorization number EU/1/22/1678/001**.

The comparator treatment arm receives **mycophenolate mofetil** in combination with **prednisolone** as standard-of-care therapy. The experimental arm receives intensified treatment consisting of voclosporin in addition to mycophenolate mofetil and prednisolone. Both treatment regimens are administered for a period of 3 months to assess residual inflammation and macrophage presence in patients with **lupus nephritis** class III/IV with or without class V disease. The study design is an **open-label randomized controlled trial** comparing the intensified triple therapy regimen to the dual therapy regimen.

Efficacy will be assessed through multiple parameters focusing on cellular, histological, and clinical endpoints. The primary endpoint involves determining differences within the macrophage spectrum between treatment arms using single-cell RNA sequencing (scRNA-seq) by comparing baseline **kidney biopsy** samples with samples obtained at 3 months of treatment. Secondary endpoints include numerical distinction of residential macrophages and monocyte-derived macrophages in kidney tissue using spatial scRNA-seq, assessment of histological response comparing intensified treatment to standard of care, and evaluation of whether early histological response is associated with clinical remission after two years. Additional secondary objectives include identification of differences in peripheral monocyte phenotype between **lupus nephritis** patients, systemic lupus erythematosus patients, and healthy subjects using bulk RNA sequencing and flow cytometric analyses, identification of non-invasive urinary biomarkers of disease activity, confirmation of scRNA-seq identified macrophage markers through immunohistochemistry with assessment of spatial distribution, and analysis of rapid clinical remission through **proteinuria** levels. The study aims to identify reliable serum and urinary biomarkers that reflect tissue damage and treatment response, with the goal of potentially rendering repeat kidney biopsies obsolete in lupus nephritis management.