Polymorphisms associated with optimization of biological therapy through drug dose reduction in moderate‐to‐severe psoriasis

Towards Personalized Medicine in Psoriasis: Current Progress

Although innovative targeted therapies have positively revolutionized psoriasis treatment shifting treatment goals to complete or almost complete skin clearance, primary or secondary lack of efficacy is still possible. Hence, identifying robust biomarkers that reflect the various clinical psoriasis phenotypes would allow stratify patients in subgroups or endotypes, and tailor treatments according to the characteristics of each individual (precision medicine). To sum up the current progress in personalized medicine for psoriasis, we performed a review on the available evidence on biomarkers predictive of response to psoriasis treatments, with focus on phototherapy and systemic agents. Relevant literature published in English was searched for using the following databases from the last five years up to March 20, 2022: PubMed, Embase, Google Scholar, EBSCO, MEDLINE, and the Cochrane library. Currently, more evidence exists towards biologicals, as justified by the huge health care costs as compared to phototherapy or conventional systemic drugs. Among them, most of the studies focused on anti-TNF and IL12/23, with still few on IL17 (mainly secukinumab). The most discussed biomarker gene is the HLA-C*02:06 status that has been shown to be associated with psoriasis, and also differential response to biologicals. Although its positivity is associated with great response to MTX, debatable results were retrieved concerning both anti-TNF and IL12/23 while it seems not to affect secukinumab response. Personalized treatment in psoriasis would provide excellent outcome minimizing the risk of side effects. To date, although several candidates were proposed and assessed, the scarcity and heterogeneity of the results do not allow the identification of the gold-standard biomarker per each treatment. Anyway, the creation of a more comprehensive panel would be more reliable for the treatment decision process.

Attitudes and behaviour regarding dose reduction of biologics for psoriasis: a survey among dermatologists worldwide

Dose reduction (DR) of biologics, where possible, seems promising for more efficient use of expensive biologics. For implementation of DR strategies, it is essential to get insight in factors that influence implementation. The objective of this study was to evaluate the attitudes and behaviour regarding dose reduction of biologic therapies for psoriasis among psoriasis expert dermatologists worldwide. A 27-question e-survey was sent through the International Psoriasis Council (IPC) to its 114 dermatologist councilors worldwide. The survey assessed demographics, general and DR prescription behaviour, and motivations for and barriers against application of DR. Of 57 respondents, 53 respondents who prescribed biologics were included for analysis. Thirty-seven (69.8%) applied DR (i.e., ‘DR dermatologists’), and 16 (30.2%) did not (i.e., ‘Non-DR dermatologists’). DR strategies varied among respondents. Regarding criteria for starting DR, differences were reported in required treatment duration, and interpretation and duration of stable low disease activity. In addition, the prolongation of intervals between injections varied between respondents. For most ‘DR dermatologists’ (n = 32/37, 86.5%), cost savings were one of the main reasons to apply DR. Fifteen out of 16 ‘Non-DR dermatologists’ (94%) did not apply DR due to lack of scientific evidence. In conclusion, DR of biologics for psoriasis is part of clinical practice in psoriasis experts globally. Barriers for applying DR included lack of evidence or guidelines, and uncertainty on DR effects and risks. Although growing evidence shows DR feasibility, future studies are needed to accumulate and broaden evidence, along with development of (inter)national guidelines on DR strategies.

Dose Tapering of Biologics in Patients with Psoriasis: A Scoping Review

Introduction

Biologics serve as a cornerstone in psoriasis treatment, with low disease activity or sometimes even clinical remission as a realistic treatment outcome. So far, it is unclear whether biologics should be tapered when this target is achieved. Dose tapering could offer potential benefits by decreasing side effects, the burden of repetitive injections and costs of biological therapy. However, clinical guidelines on dose tapering of biologicals in psoriasis patients are lacking. This scoping review was conducted to provide an overview of the current literature on dose tapering and offer guidance for clinicians in daily clinical practice.

Methods

Dose tapering is defined as the administration of a lower dose per administration, or the prolongation of the regular dose interval, after initial treatment according to the standard dosing. Four electronic databases (PubMed, EMBASE, Cochrane, and Web of Science) were systematically searched for literature on tapering of biologics in adult patients with psoriasis from 1 January 2000.

Results

We included 19 original articles on biologic tapering in psoriasis patients: four randomized controlled trials and 15 observational studies. Tapering eligibility criteria, tapering strategies, tapering outcomes, and recapture of response after relapse were assessed. Furthermore, the available evidence on possible predictors for successful tapering, and the effect of tapering on safety, quality of life and costs is summarized. The definition of low disease activity as a measure for tapering eligibility varied widely. Beside tapering criteria, tapering strategies were also heterogeneous. Of note, quality-of-life measurements were barely integrated in the evaluation of tapering outcomes. Literature on regaining response after relapse due to tapering was limited, but restored remission has been described. The included studies did not proclaim a significant effect of tapering on the occurrence of (severe) adverse events. Even though cost savings have been reported, no proper cost-effectiveness analysis has been conducted yet.

Conclusion

Biologic tapering seems to be effective and safe in psoriasis patients with stable low disease activity or clinical remission. Available data on biologic dose tapering in patients with psoriasis are promising, but more research is warranted to fill the current gaps in knowledge.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40265-020-01448-z.

Biologics are effective in treating psoriasis amongst other diseases, such as rheumatoid arthritis and Crohn’s disease. However, biologics are costly, and can cause side effects, such as an increased risk of infection. In patients with rheumatoid arthritis, it is not uncommon to lower the dose of these biologics (also called “dose tapering”), once stable low disease activity, or even remission, is reached. However, in psoriasis patients, dose tapering of biologics is not common practice. In this “scoping review,” we provide an overview of the available literature on dose tapering of biologics in adult patients with plaque psoriasis in order to address the current gaps in literature. We found 19 studies that addressed dose tapering. These studies used different criteria to determine which patients were eligible for tapering, which led to various interpretations of tapering success. This made it difficult for us to draw general conclusions on which tapering criteria and strategies should be further investigated. Dose tapering seems to be effective and safe in patients with a stable low disease activity, although more (high-quality) research is needed. Future studies should focus on generating more data on long-term safety, finding predictors for successful tapering, calculating the cost-effectiveness of dose tapering, and evaluating dose tapering in the newest generation of biologics.

Pharmacogenetics Update on Biologic Therapy in Psoriasis

Background and objectives: Psoriasis is a chronic immune-mediated skin disease caused by several complex factors, both environmental and genetic, many of which are still not fully understood. Nowadays, several groups of biological drugs are being used for psoriasis treatment. Although these therapies are very effective, they show significant variability in efficacy among individuals. Therefore, there is a need for biomarkers to predict treatment outcomes in order to guide personalized therapeutic decisions. Pharmacogenetics is the study of variations in DNA sequences related to drug response. Materials and Methods: In this article, we review pharmacogenetics studies on the treatment of moderate-to-severe psoriasis focusing on anti-interleukin (IL) 12/23 (ustekinumab) and anti-IL17 drugs (secukinumab and ixekizumab), as well as recent studies concerning anti-TNF drugs. Results: Several polymorphisms have been studied over the years in reference to anti-TNF drugs; some of the most recent studies included the performance of a genome-wide association study (GWAS) and pharmacogenetics studies focused on the optimization of a treatment regimen. Various polymorphisms in different genes have been related to ustekinumab response; among them, the most commonly studied is the HLA-C*06:02 allele. Conclusions: Although not confirmed in some studies, most studies have shown that patients carrying this allele present a significantly higher response rate to ustekinumab. Some polymorphisms have been studied in patients treated with anti-IL17 drugs, mostly related to secukinumab; however, up to now, no association has been found between any of these polymorphisms and response. Nevertheless, further studies involving larger cohorts are needed in order to confirm these results before the implementation of this biomarker in clinical practice.