Moderator's view: The use of calcineurin inhibitors in the treatment of lupus nephritis

Induction and Maintenance Treatment of Lupus Nephritis: A Comprehensive Review of Meta-Analyses

BACKGROUND

Lupus nephritis (LN) is present in over 50% of patients with systemic lupus erythematosus (SLE) which is managed with immunosuppressive and immunomodulatory therapies. However, several novel therapeutic approaches for LN are under investigation due to the adverse effects spectrum of conventional therapy; Methods: We performed a comprehensive review of meta-analyses aggregating the comparative efficacies of various pharmacotherapies for LN. We conducted a literature search and retrieved a total of 23 meta-analyses and network meta-analyses for summarization. Pharmacotherapies were evaluated across six major outcomes: remission, relapse, mortality, end stage kidney disease (ESKD) progression, infection, and malignancy.

RESULT

Calcineurin inhibitors (CNI), particularly tacrolimus (TAC), in combination with glucocorticoids (GC) outperformed cyclophosphamide (CPA) with GC in the rate of remission, either complete or partial remission, and in terms of infectious complications. In maintenance therapy, MMF was superior to azathioprine (AZA) as the MMF-treated patients had lower relapse rate.

INTERPRETATION

This review aggregates evidence of therapy for clinicians and sheds light on comparative efficacies of alternative LN treatments. As more promising agents are entering the market, such as voclosporin, belimumab, and obinutuzumab, LN management might undergo significant changes during the next years.

Voclosporin: a novel calcineurin inhibitor with no impact on mycophenolic acid levels in patients with SLE

Background

An open-label phase 1 study was conducted to evaluate the effect of voclosporin following dosing with mycophenolate mofetil (MMF) on blood levels of mycophenolic acid (MPA, the active moiety of MMF) and MPA glucuronide (MPAG, the pharmacologically inactive metabolite of MMF) in subjects with systemic lupus erythematosus (SLE) and to assess the safety and tolerability of the combination.

Methods

MMF was orally administered at a dose of 1 g twice a day for at least 28 days prior to the study and continued at the same dose throughout the study. Voclosporin was orally administered at a dose of 23.7 mg twice a day for 7 consecutive days (Days 1–7), starting on the evening of Day 1 and ending with the morning dose on Day 7. Dense pharmacokinetic blood samples were collected pre-dose in the morning and from 0.25 to 12 h after the morning doses. Analyses were derived by non-compartmental methods.

Results

In 24 patients, MPA exposure [maximum serum concentration (C_max) and area under the concentration curve from time 0 to 12 h (AUC_0–12)] was similar in the presence and absence of voclosporin, with treatment ratios of 0.94 and 1.09, respectively [C_max 16.5 μg/mL (Day 1) versus 15.8 (Day 7), AUC_0–12 39.1 μg/h/mL (Day 1) versus 40.8 (Day 7)]. MPAG exposure showed a small increase in the presence of voclosporin (12% for C_max and 27% for AUC_0–12). Combination therapy was well tolerated.

Conclusions

There is no clinically meaningful interaction between voclosporin and MMF. As changes in exposure to MPA may affect efficacy and safety, these data confirm that voclosporin and MMF can be administered concomitantly without the need for dose adjustment.

Efficacy of Belimumab for active lupus nephritis in a young Hispanic woman intolerant to standard treatment: a case report

Background

Lupus nephritis (LN) is a frequent severe complication of Systemic Lupus Erythematosus (SLE), especially in patients of non-Caucasian ethnicity. Induction treatment for LN consists in the combination of steroids plus a second agent (cyclophosphamide or mycophenolate mofetil) or, as a second-line, calcineurin inhibitors or Rituximab. Induction treatment for LN can be complicated by a series of side effects, the most severe being serious infections. Belimumab is a fully humanized monoclonal antibody that targets soluble B lymphocyte stimulator (BLyS), approved for treatment of serologically active SLE in addition to standard of care.

Case presentation

A young Hispanic woman was diagnosed with SLE at the age of 15. After several immunosuppressive treatments for arthritic symptoms (high-dose steroids, mycophenolate mofetil, Rituximab, cyclophosphamide) leading to serious complications and scarce clinical improvement, she developed severe LN. Induction treatment with a combination of intravenous high-dose methylprednisolone and cyclophosphamide was started but, after few days, the patient developed cryptococcal meningitis. After institution of appropriate antifungal therapy, treatment with Tacrolimus was attempted but poorly tolerated by the patient and withdrawn. Eventually, Belimumab was initiated off-label as a last resource to treat LN. Belimumab was well tolerated by the patient and resulted in a rapid and marked improvement in clinical symptoms and reduction in proteinuria, serum complement levels and anti-dsDNA titer; of note, the patient developed no infectious complications.

Conclusions

We report the case of a severe LN in a young Hispanic woman who did not respond to conventional and second-line induction therapies, due both to intolerance and to the development of serious infectious complications. Eventually, Belimumab was successfully added to steroids and was well tolerated by the patient, resulting in a marked improvement in clinical and biochemical parameters. We suggest that Belimumab should be considered as a potentially efficacious treatment in patients with LN who cannot tolerate conventional therapies.

Calcineurin inhibitors in systemic lupus erythematosus

The calcineurin inhibitors (CNIs) belong to a group of immunosuppressive agents that block T-cell activation through the suppression of the calcium/calcimodulin-dependent phosphatase calcineurin. Agents such as cyclosporine A (CSA) and tacrolimus (TAC) have long been used in patients with systemic lupus erythematosus (SLE). TAC is preferred to CSA in SLE because of the lower frequency of cosmetic, hypertensive and dyslipidemic adverse effects. Recent randomised controlled trials have demonstrated noninferiority of TAC to mycophenolate mofetil (MMF) or cyclophosphamide (CYC) for induction therapy of lupus nephritis. Low-dose combination of TAC and MMF has also been shown to outperform CYC pulses in inducing remission of lupus nephritis in Chinese patients. TAC does not affect fertility and is relatively safe in pregnancy. In SLE patients who are intolerant or refractory to conventional immunosuppressives, or where contraindications to other immunosuppressive agents exist, TAC is an alternative option. However, the therapeutic window of TAC is narrow, and drug level monitoring is required to ensure drug exposure and minimise toxicities. Current evidence of TAC in lupus nephritis is limited to 6 months, and its long-term safety as maintenance therapy of SLE is yet to be determined. Newer chemical analogues of CNIs, such as voclosporin, with less variable plasma concentration are being tested in lupus nephritis.