Calcipotriene/betamethasone in the treatment of psoriasis: a review article

An overview of topical lipid-based and polymer-based nanocarriers for treatment of psoriasis

Psoriasis is a consistently recurring, inflammatory skin disease, affecting about 2 - 5 % of the world population. Different types of psoriasis can be observed such as guttate psoriasis, pustular psoriasis, psoriatic arthritis, scalp psoriasis, flexural psoriasis etc. Several therapeutic approaches are available for the treatment of psoriasis. However, none of them are entirely safe and effective to treat the disease without compromising patient compliance. The traditional treatment plan is associated with harmful side effects such asimmune system suppression and damage of essential organs at high doses, which poses a challenge to treat psoriasis. Novel drug delivery systems are being developed to replace traditional therapy in order to address these shortcomings. Currently, nanoformulations have gained widespread application for treatment of psoriasis. Researchers have developed different types of lipid-based nanoparticles like liposomes, niosomes, ethosomes, transethosomes, nanostructured lipid carriers and solid lipid nanoparticles. These innovative formulations provide advantages in terms of reduction in dose, dosing frequency, dose-dependency with enhanced efficacy, improved encapsulation efficiency, controlled release, increased surface area, high bioavailability and greater stratum corneum permeability. This review highlights detailed and comparative discussion of lipid-based and polymer-based nanoparticles for psoriasis along with the pathophysiology and other treatments of psoriasis.

The Treatment of Nail Psoriasis: A Review

Nail disease affects most patients with psoriasis and has a substantial medical and psychological impact on the lives of those affected. Frequently, nail psoriasis is associated with severe pain, restriction in daily activity, and emotional agony that require the dermatologist to know the most up-to-date therapies. Unfortunately, no single treatment is paramount, and the choice of therapy must be individualized to disease severity, patient tolerability, cost, and risk of adverse events. Some clinical manifestations include nail pitting, discoloration, onycholysis, subungual hyperkeratosis, and splinter hemorrhages. Currently, no standardized therapeutic regimen exists; and, given the variability in clinical manifestations, multiple modalities may be needed for adequate results. More recently added to the armamentarium of topical and injectable therapies for nail disease are systemic agents, such as biologics, and photochemotherapeutic treatments. These therapies have been used with varying degrees of success. This review highlights the current treatments available for the treatment of nail psoriatic disease.

Differential effects of phototherapy, adalimumab and betamethasone-calcipotriol on effector and regulatory T cells in psoriasis

BACKGROUND

Psoriasis is a chronic T-cell-mediated skin disease with marked social and economic burdens. Current treatments are unsatisfactory, with unpredictable remission times and incompletely understood modes of action. Recent advances in our understanding of the pathogenesis of psoriasis have identified the imbalance between CD4⁺ T effector cells, particularly the T helper (Th)17 subset, and regulatory T cells (Tregs) as key to the development of psoriatic lesions, and therefore a novel therapeutic target.

OBJECTIVES

To quantify in patients the effects of three commonly used psoriasis treatment modalities on the Th1, Th2, Th17 and Treg subsets, and to test whether any change correlates with clinical response.

METHODS

Flow cytometry was used to enumerate Th1, Th2, Th17 and Treg subsets in blood and skin of patients with psoriasis before and after receiving any of the following treatments: narrowband ultraviolet B (NB-UVB), adalimumab and topical betamethasone-calcipotriol combination (Dovobet^® ) RESULTS: All patients responded clinically to the treatments. NB-UVB significantly increased the numbers of circulating and skin Tregs, while, by contrast, adalimumab reduced Th17 cells in these compartments, and Dovobet had dual effects by both increasing Tregs and reducing Th17 cells.

CONCLUSIONS

The differential effects reported here for the above-mentioned treatment modalities could be exploited to optimize or design therapeutic strategies to overcome the inflammatory drivers more effectively and restore the Th17-Treg balance in psoriasis.

GILZ regulates Th17 responses and restrains IL-17-mediated skin inflammation

Patients with inflammatory autoimmune diseases are routinely treated with synthetic glucocorticoids to suppress immunopathology. A crucial outcome of glucocorticoid exposure is induction of glucocorticoid-induced leucine zipper (GILZ), a protein with multiple functions that include inhibition of key immune cell signalling pathways. Here we report that GILZ maintains a threshold for activation of Th17 responses and IL-17-dependent pathology. GILZ expression was deficient in lesional skin of psoriasis patients and was negatively correlated with the pro-inflammatory cytokines IL-23, IL-17A and IL-22, and with STAT3 expression. Deficiency of GILZ in mice resulted in excessive inflammation and pro-inflammatory cytokine expression in the imiquimod model of psoriasis, and dendritic cells lacking GILZ produced greater IL-1, IL-23 and IL-6 in response to imiquimod stimulation in vitro. These cytokines stimulate Th17 cell differentiation, and we found unchallenged GILZ-deficient mice to have spontaneous production of IL-17A and IL-22 in vivo. We also identified a T cell-intrinsic role for GILZ in limiting Th17 cell formation in vitro in response to Th17-promoting cytokines IL-1β and IL-23. Addition of IL-6 under these conditions suppressed GILZ, allowing T cell proliferation and expression of Th17 genes, whereas exogenous delivery of GILZ using a cell-permeable fusion protein restored regulation of Th17 cell proliferation. Thus, GILZ has a non-redundant function to constrain pathogenic Th17 responses, with clinical implications for psoriasis.

Calcipotriol delivery into the skin with PEGylated liposomes

The D-vitamin analogue calcipotriol is commonly used for topical treatment of psoriasis, but skin penetration is required for calcipotriol to reach its pharmacological target: the keratinocytes in the lower epidermis. Liposomes can enhance the delivery of drugs into the skin, but a major challenge for the development of dosage forms containing liposomes is to maintain the colloidal stability in the formulation. The purpose of this study was to investigate the effect of stabilising liposomes with the lipopolymer poly(ethylene glycol)-distearoylphosphoethanolamine (PEG-DSPE) on the physicochemical properties of the liposomes and the ability to deliver membrane-intercalated calcipotriol into the skin. Inclusion of 0.5, l and 5 mol% PEG-DSPE in the membrane enhanced the colloidal stability of the liposomes without compromising the delivery of calcipotriol from the vehicle into excised pig skin. Calcipotriol-loaded liposomes with 1 mol% PEG-DSPE did even provide for a significantly increased deposition of calcipotriol into the stratum corneum. The size of the liposomes affected the penetration of calcipotriol into the stratum corneum since small unilamellar vesicles enhanced calcipotriol penetration as compared to large multilamellar vesicles, indicating that the liposomes to some extent migrate as intact vesicles into the stratum corneum. However, calcipotriol penetrated the skin better than the lipid component of the liposomes, suggesting that at least a fraction of the drug is released from the liposomes during skin migration. In conclusion, PEGylation is therefore a promising approach for stabilising calcipotriol-containing liposomal dispersions without compromising their favourable skin accumulation properties.

Mechanisms of action of topical corticosteroids in psoriasis

Psoriasis is a lifelong, chronic, and immune-mediated systemic disease, which affects approximately 1-3% of the Caucasian population. The different presentations of psoriasis require different approaches to treatment and appropriate prescriptions according to disease severity. The use of topical therapy remains a key component of the management of almost all psoriasis patients, and while mild disease is commonly treated only with topical agents, the use of topical therapy as adjuvant therapy in moderate-to-severe disease may also be helpful. This paper focuses on the cutaneous mechanisms of action of corticosteroids and on the currently available topical treatments, taking into account adverse effects, bioavailability, new combination treatments, and strategies to improve the safety of corticosteroids. It is established that the treatment choice should be tailored to match the individual patient's needs and his/her expectations, prescribing to each patient the most suitable vehicle.

Calcipotriol/betamethasone dipropionate: a review of its use in the treatment of psoriasis vulgaris of the trunk, limbs and scalp

Calcipotriol/betamethasone dipropionate (calcipotriol 50 μg/g and betamethasone 0.5 mg/g) is a fixed-dose combination of a vitamin D(3) analogue and a corticosteroid indicated for the once-daily, topical treatment of psoriasis vulgaris of the trunk, limbs and scalp in adults. Both the ointment (Daivobet®; Dovobet®) and gel (Xamiol®; Daivobet® Gel; Dovobet® Gel) formulations of calcipotriol/betamethasone dipropionate can be used to treat psoriasis vulgaris of the trunk and/or limbs, although the gel formulation was specifically developed for the treatment of scalp psoriasis. This article reviews the efficacy and tolerability of calcipotriol/betamethasone dipropionate in patients with psoriasis vulgaris, as well as summarizing its pharmacological properties. Calcipotriol/betamethasone dipropionate has low systemic absorption and displays local anti-inflammatory and immunoregulatory properties. It reduces the hyperproliferation of keratinocytes and helps normalize keratinocyte differentiation. In large, well designed clinical trials, calcipotriol/betamethasone dipropionate, either as the ointment or the gel formulation, applied once daily for 4-8 weeks, was more effective than placebo, calcipotriol and tacalcitol, as well as betamethasone dipropionate in most instances, for the topical, symptomatic treatment of psoriasis vulgaris of the trunk/limbs. Likewise, calcipotriol/betamethasone dipropionate gel applied once daily for 8 weeks was more effective than placebo or either component alone in the topical, symptomatic treatment of psoriasis vulgaris of the scalp. Long-term, once-daily, when required therapy with calcipotriol/betamethasone dipropionate for 52 weeks was more effective than calcipotriol alone for the treatment of scalp psoriasis, and was at least as effective as switching to calcipotriol for 48 weeks after 4 weeks of calcipotriol/betamethasone dipropionate or alternating between calcipotriol/betamethasone dipropionate and calcipotriol every 4 weeks for 52 weeks in the treatment of psoriasis vulgaris of the trunk/limbs. Calcipotriol/betamethasone dipropionate also improved health-related quality of life. Calcipotriol/betamethasone dipropionate was generally well tolerated, with most adverse drug reactions being lesional or perilesional effects of mild or moderate severity. Calcipotriol/betamethasone dipropionate was often associated with fewer lesional/perilesional adverse reactions than calcipotriol or tacalcitol and did not appear to be associated with a higher incidence of corticosteroid-related adverse events during long-term therapy. Pharmacoeconomic analyses predicted calcipotriol/betamethasone dipropionate to be more cost effective than other topical therapies. Thus, calcipotriol/betamethasone dipropionate is an important, effective, once-daily, topical therapy for the symptomatic treatment of psoriasis vulgaris of the trunk, limbs and scalp.

Topical delivery for the treatment of psoriasis

IMPORTANCE OF THE FIELD

Psoriasis is one of the most common human skin diseases. Topical therapy forms the cornerstone in the management of mild-to-moderate psoriasis. Topical therapies are also used as adjunctive to systemic therapy in moderate and severe forms of the disease.

AREAS COVERED IN THIS REVIEW

In this review, an overview of psoriasis pathogenesis, new topical medications for psoriasis, new targets and molecules, combination topical therapies and combination of topical and phototherapy is provided. Over the past decade several efficacious and acceptable treatment options have emerged from the age-old therapies. The development of sophisticated formulation options has led to an enhancement in the rate and extent of drug delivery across the skin, increasing therapeutic value and improving patient compliance.

WHAT THE READER WILL GAIN

Readers will learn about monotherapy and combination topical products as well as new topical drug delivery technology to achieve optimal clinical outcomes. This review will highlight the need to generate more dermal pharmacokinetic data for better understanding of the impact of formulation change on skin pharmacokinetics to help design improved topical drug delivery systems.

TAKE HOME MESSAGE

New topical formulations have the potential to achieve better efficacy with improved safety profile.

Vitamin D effects on pregnancy and the placenta

Vitamin D is a pleiotropic secosteroid hormone important for health and disease prevention. The actions of vitamin D are mediated by the vitamin D receptor that binds the active form of vitamin D [1,25(OH)(2)D] to induce both transcriptional and non-genomic responses. Vitamin D has well known classical functions in calcium uptake and bone metabolism, but more recent work highlights the importance of the nonclassical actions of vitamin D in a variety of cell types. These actions include modulation of the innate and adaptive immune systems and regulation of cell proliferation. Adequate vitamin D intake is essential for maternal and fetal health during pregnancy, and epidemiological data indicate that many pregnant women have sub-optimal vitamin D levels. Notably, vitamin D deficiency correlates with preeclampsia, gestational diabetes mellitus, and bacterial vaginosis, and an increased risk for C-section delivery. Recent work emphasizes the importance of nonclassical roles of vitamin D in pregnancy and the placenta. The placenta produces and responds to vitamin D where vitamin D functions as a modulator of implantation, cytokine production and the immune response to infection. We describe vitamin D metabolism and the cellular responses to vitamin D, and then summarize the role of vitamin D in placental trophoblast, pregnancy and the fetus.

Vitamin D effects on pregnancy and the placenta

Vitamin D is a pleiotropic secosteroid hormone important for health and disease prevention. The actions of vitamin D are mediated by the vitamin D receptor that binds the active form of vitamin D [1,25(OH)(2)D] to induce both transcriptional and non-genomic responses. Vitamin D has well known classical functions in calcium uptake and bone metabolism, but more recent work highlights the importance of the nonclassical actions of vitamin D in a variety of cell types. These actions include modulation of the innate and adaptive immune systems and regulation of cell proliferation. Adequate vitamin D intake is essential for maternal and fetal health during pregnancy, and epidemiological data indicate that many pregnant women have sub-optimal vitamin D levels. Notably, vitamin D deficiency correlates with preeclampsia, gestational diabetes mellitus, and bacterial vaginosis, and an increased risk for C-section delivery. Recent work emphasizes the importance of nonclassical roles of vitamin D in pregnancy and the placenta. The placenta produces and responds to vitamin D where vitamin D functions as a modulator of implantation, cytokine production and the immune response to infection. We describe vitamin D metabolism and the cellular responses to vitamin D, and then summarize the role of vitamin D in placental trophoblast, pregnancy and the fetus.