Selective Janus Kinase 1 Inhibition Is a Promising Therapeutic Approach for Lupus Erythematosus Skin Lesions.

Background: Cutaneous lupus erythematosus (CLE) is an interferon (IFN) -driven autoimmune skin disease characterized by an extensive cytotoxic lesional inflammation with activation of different innate immune pathways. Aim of our study was to investigate the specific role of Janus kinase 1 (JAK1) activation in this disease and the potential benefit of selective JAK1 inhibitors as targeted therapy in a preclinical CLE model. Methods: Lesional skin of patients with different CLE subtypes and healthy controls (N = 31) were investigated on JAK1 activation and expression of IFN-associated mediators via immunohistochemistry and gene expression analyses. The functional role of JAK1 and efficacy of inhibition was evaluated in vitro using cultured keratinocytes stimulated with endogenous nucleic acids. Results were confirmed in vivo using an established lupus-prone mouse model. Results: Proinflammatory immune pathways, including JAK/STAT signaling, are significantly upregulated within inflamed CLE skin. Here, lesional keratinocytes and dermal immune cells strongly express activated phospho-JAK1. Selective pharmacological JAK1 inhibition significantly reduces the expression of typical proinflammatory mediators such as CXCL chemokines, BLyS, TRAIL, and AIM2 in CLE in vitro models and also improves skin lesions in lupus-prone TREX1-/- -mice markedly. Conclusion: IFN-associated JAK/STAT activation plays a crucial role in the pathophysiology of CLE. Selective inhibition of JAK1 leads to a decrease of cytokine expression, reduced immune activation, and decline of keratinocyte cell death. Topical treatment with a JAK1-specific inhibitor significantly improves CLE-like skin lesions in a lupus-prone TREX1-/- -mouse model and appears to be a promising therapeutic approach for CLE patients.

A pre-clinical quantitative model predicts the pharmacokinetics/pharmacodynamics of an anti-BDCA2 monoclonal antibody in humans.

BIIB059 is a novel humanized monoclonal antibody (mAb) that is currently under development for the treatment of Systemic Lupus Erythematosus and Cutaneous Lupus Erythematosus. BIIB059 is targeted against the blood dendritic cell antigen 2 (BDCA2), a receptor exclusively expressed on the surface of plasmacytoid dendritic cells (pDCs). Herein, we utilized pre-clinical pharmacokinetic (PK) and pharmacodynamic (PD) data to develop a non-human primate (NHP) model and to address whether the NHP model can be successfully scaled to predict the human PK/PD. In particular, PK data from 17 cynomolgus monkeys were utilized for PK model development, wherein BIIB059 was administered intravenously (1 and 10 mg/kg single-dosing and 5 mg/kg multiple-dosing) or subcutaneously (0.2 and 7.5 mg/kg single-dosing). Additionally, PD data (BDCA2 receptor density on pDCs) from 6 cynomolgus monkeys were used for the development of the PD model. The developed NHP two-compartment PK model, linked with an indirect response PD model, was subsequently scaled to humans by combining traditional allometric PK scaling with sensitivity-analysis-driven scaling of the PD. The scaled PK/PD model was then used to simulate the human PK/PD for different dose levels. When clinical data from the BIIB059 Phase I study became available, they were used to evaluate the predictability of the scaled PK/PD model and the model simulations were in agreement with the clinical data. Therefore, the presented approach is suggested to be employed in scaling pre-clinical mAb models to support the selection of safe first-in-human doses and, more broadly, the prediction of PK/PD in the clinic.

Subacute cutaneous lupus erythematosus: a case report of Polypodium leucotomos as an adjuvant therapy.

Subacute cutaneous lupus erythematosus (SCLE) is an uncommon autoimmune disease that results in substantial photosensitivity of affected patients. Eruptions often are triggered or exacerbated by UV light (UVL) exposure. We present a case of a patient with SCLE who was moderately controlled with hydroxychloroquine sulfate but achieved near total remission of disease after the addition of oral Polypodium leucotomos supplement which has photoprotective effects on human keratinocytes. We report sustained clinical response with the use of P leucotomos in lupus and suggest that it may have future application in photosensitizing dermatoses.

Cutaneous lupus erythematosus: update of therapeutic options part II.

In the first part of the review, topical agents and first-line systemic treatment options for cutaneous lupus erythematosus were discussed whereas in the second part, recent information on efficacy, dosage, and side effects for further systemic treatment options are described in detail. In contrast to other immunosuppressive agents, such as azathioprine, cyclophosphamide, and cyclosporine, methotrexate has recently received more attention in the treatment of the disease. Further second-line treatment includes retinoids, dapsone, and mycophenolate mofetil. Because of severe side effects or high costs, other agents, such as thalidomide or high-dose intravenous immunoglobulins, are reserved for severe recalcitrant CLE. Biologics, ie, rituximab, have been used to treat systemic lupus erythematosus; however, in CLE, most biologics have only been applied in single cases. In addition to successful treatment, induction of CLE subtypes by biologics has been reported. In conclusion, many treatment options exist for CLE, but not many are supported by evidence from randomized controlled trials.

Extracorporeal photochemotherapy in cutaneous lupus erythematosus.

We report two female subjects with therapy-resistant cutaneous lupus erythematosus (LE), one with subacute cutaneous and the other chronic discoid LE, both treated with extracorporeal photochemotherapy (ECP). The responses after six and eight cycles of ECP led to a prolonged remission of 18 and 11 months, respectively. ECP seems to be a treatment option for patients not responding to or showing unwanted side-effects during conventional standard therapy.

Evaluation of the Japanese-Chinese herbal medicine, kampo, for the treatment of lupus dermatoses in autoimmune prone MRL/Mp-lpr/lpr mice.

Kampo, a Japanese-Chinese traditional herbal medicine, has been used for the treatment of various diseases for about 3,000 years in China. Among herbal medicines, Sairei-to is well known for improving the symptoms of rheumatoid arthritis (RA) and other collagen diseases. However, its immunosuppressive effects on autoimmune cutaneous phenomena are not completely understood. We investigated the effects of Sairei-to on the development of lupus dermatoses in autoimmune-prone MRL/Mp-lpr/lpr (MRL/lpr) mice, an animal model which spontaneously develops skin lesions similar to those seen in human lupus erythematosus. Virgin female MRL/lpr mice at 1 month of age, which were treated orally with Sairei-to, had reduced amounts of IgG deposition at the dermoepidermal junction, titers of anti-DNA antibodies and rheumatoid factor, and lymphoproliferation. These results support the use of traditional herbal medicines in patients with human RA and systemic lupus erythematosus.

Subacute cutaneous lupus erythematosus during PUVA therapy for psoriasis: case report and review of the literature.

Lesions typical of subacute cutaneous lupus erythematosus developed in an elderly woman after 6 months of PUVA (8-methoxypsoralen and longwave ultraviolet light) therapy for psoriasis. Pancytopenia, antibodies to double-stranded DNA, and hypocomplementemia developed concurrently with the appearance of the cutaneous lesions. With discontinuation of photochemotherapy, the cutaneous lesions disappeared and the pancytopenia improved.