Next stop in the treatment of refractory systemic lupus erythematosus: B-cell targeted combined therapy

From systemic lupus erythematosus to lupus nephritis: The evolving road to targeted therapies

Systemic lupus erythematosus is a chronic autoimmune disease characterized by loss of tolerance against nuclear and cytoplasmic self-antigens, induction of immunity and tissue inflammation. Lupus nephritis (LN), the most important predictor of morbidity in SLE, develops in almost 30% of SLE patients at disease onset and in up to 50-60% within the first 10 years. Firstly, in this review, we put the pathogenic mechanisms of the disease into a conceptual frame, giving emphasis to the role of the innate immune system in this loss of self-tolerance and the induction of the adaptive immune response. In this aspect, many mechanisms have been described such as dysregulation and acceleration of cell-death pathways, an aberrant clearance and overload of immunogenic acid-nucleic-containing debris and IC, and the involvement of antigen-presenting cells and other innate immune cells in the induction of this adaptive immune response. This result in a clonal expansion of autoreactive lymphocytes with generation of effector T-cells, memory B-cells and plasma cells that produce autoantibodies that will cause kidney damage. Secondly, we review the immunological pathways of damage in the kidney parenchyma, initiated by autoantibody binding and immune complex deposition, and followed by complement-mediated microvascular injury, activation of kidney stromal cells and the recruitment of leukocytes. Finally, we summarize the rationale for the treatment of LN, from conventional to new targeted therapies, focusing on their systemic immunologic effects and the minimization of podocytary damage.

Refractory Systemic Lupus Erythematosus: Identification and Pharmacological Management

Systemic lupus erythematosus (SLE) is characterized by an aberrant immune response, leading to an extremely heterogeneous clinical presentation, potentially affecting different systems and organs. Despite the fact that SLE mortality has greatly decreased since the introduction of steroids, some forms of refractory/severe SLE still have the potential to result in permanent organ damage as well as increased mortality and morbidity. Furthermore, SLE patients with multiple comorbidities may face a clinical conundrum and have a bad prognosis. An improved prognosis for severe refractory SLE depends on prompt and appropriate treatment. Due to the scarcity of solid data from a well-characterized group of patients with refractory/severe SLE coming from randomized controlled studies, this review aims to shed light on this with real-world evidence from clinical research performed at our Unit, the University Center of Excellence on Nephrologic, Rheumatologic and Rare Diseases with Nephrology and Dialysis Unit and Center of Immuno-Rheumatology and Rare Diseases (CMID) (Turin, Italy). In order to determine the key clinical and prognostic features, and therapeutic approaches for severe and/or refractory SLE, our experience will be described together with existing literature, primarily focused on dermatological, neuropsychiatric, and renal symptoms.

Belimumab: A BAFF-specific Inhibitor for the Treatment of Systemic Lupus Erythematosus and Lupus Nephritis

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that affects multiple organs. In particular, the presence of renal involvement, known as lupus nephritis, is a major determinant of prognosis. Conventional treatments for SLE include hydroxychloroquine, glucocorticoid and immunosuppressive agents. However, the use of such non-specific drugs increases the risk of side effects, such as infections. Soluble B-cell-activating factor (BAFF), belonging to the tumour necrosis factor family, is produced by dendritic cells and induces class switching of B cells and differentiation into antibody-producing cells. International phase III studies demonstrated the efficacy and safety of belimumab (a monoclonal antibody against soluble BAFF) not only in patients with SLE, but also in those with active lupus nephritis. There were no significant differences between the belimumab and placebo groups in the incidence of adverse events, including serious events and events necessitating drug cessation. Thus, belimumab could become an alternative induction treatment for lupus nephritis. This article describes the pathogenesis of SLE and lupus nephritis, and reviews the results of recent phase III trials of belimumab and its promising role for the treatment of patients.