Quality of life, treatment satisfaction and efficacy of non-biological systemic therapies in patients with plaque psoriasis: study protocol for a prospective observational study.

INTRODUCTION: Psoriasis vulgaris often leads to a significant impaired quality of life and dissatisfaction with the existing therapeutic approaches. However, patients' quality of life and treatment satisfaction are of utmost importance, since it is positively related to therapy adherence and encourages patient's compliance. The study described herein evaluates the quality of life, treatment satisfaction and efficacy during the initial 6 months of treatment with a non-biological systemic agent in a real-life clinical setting. METHODS AND ANALYSIS: This observational study compares quality of life, treatment satisfaction and the efficacy of non-biological systemic therapy between 60 patients suffering from plaque psoriasis receiving the non-biological systemic therapies with apremilast, methotrexate and fumaric acid esters. ETHICS AND DISSEMINATION: Ethics approval was provided by the ethics committee of the medical faculty of the University of Heidelberg. Ethics approval number is S-298/2015. The design and the final results of the study will be published and made available to the public. TRIAL REGISTRATION NUMBER: German Clinical Trial Register (DRKS): DRKS00008721 (https://www.germanctr.de/).

The phosphodiesterase 4 inhibitor apremilast inhibits Th1 but promotes Th17 responses induced by 6-sulfo LacNAc (slan) dendritic cells.

BACKGROUND: The phosphodiesterase 4 (PDE4) inhibitor apremilast increases cellular cAMP levels and has proven effective in the treatment of psoriasis and psoriasis arthritis. We recently described 6-sulfo LacNAc dendritic cells (slanDCs) as immature DCs in blood and as a subset of inflammatory dermal DCs in psoriasis with a pronounced capacity to produce proinflammatory cytokines and to program Th17/Th1 T cell responses. OBJECTIVE: The aim of this study was to investigate possible immune regulatory effects of the PDE4 inhibitor apremilast on slanDCs. METHODS: In vitro studies were performed analyzing the effects of apremilast on the proinflammatory function of slanDCs and their capacity to induce Th1/Th17-biased T cell responses. RESULTS: Increasing cAMP levels in slanDCs by PDE4 inhibition strongly reduced production of IL-12 and TNF-α. In line with these findings, co-culture experiments with apremilast-pulsed slanDCs and allogeneic T cells either from psoriasis patients or healthy controls, revealed a significant reduction of IFN-γ production and expression of the transcription factor T-bet. In parallel, production of IL-23 and IL-1ß by slanDCs was increased and co-cultured T cells revealed a largely augmented IL-17 production and an upregulated RORyt expression. CONCLUSIONS: We here demonstrate anti-inflammatory as well as Th17-promoting effects of apremilast when studying blood precursors of human inflammatory dermal dendritic cells. In the concert of the broad anti-inflammatory effects of apremilast on keratinocytes, fibroblasts and endothelial cells, the dual effect on slan+ inflammatory dermal DCs should be taken into account and may constrain therapeutic responses.