Apremilast mechanism of action and application to psoriasis and psoriatic arthritis. Biochem Pharmacol. 2012;83:1583-1590. [PMID: 22257911 DOI: 10.1016/j.bcp.2012.01.001]

The Changing Landscape of Alopecia Areata: The Therapeutic Paradigm

Alopecia areata (AA), a prevalent inflammatory cause of hair loss, lacks FDA-approved therapeutics for extensive cases, which are associated with very poor rates of spontaneous hair regrowth and major psychological distress. Current treatments for severe cases include broad immune-suppressants, which are associated with significant adverse effects, precluding long-term use, with rapid hair loss following treatment termination. As a result of the extent of the disease in severe cases, topical contact sensitizers and intralesional treatments are of limited use. The pathogenesis of AA is not yet fully understood, but recent investigations of the immune activation in AA skin reveal Th1/IFN-γ, as well as Th2, PDE4, IL-23, and IL-9 upregulations. Tissue analyses of both animal models and human lesions following broad-acting and cytokine-specific therapeutics (such as JAK inhibitors and ustekinumab, respectively) provide another opportunity for important insights into the pathogenesis of AA. As reviewed in this paper, numerous novel therapeutics are undergoing clinical trials for AA, emphasizing the potential transformation of the clinical practice of AA, which is currently lacking. Dermatologists are already familiar with the revolution in disease management of psoriasis, stemming from better understanding of immune dysregulations, and atopic dermatitis will soon follow a similar path. In light of these recent developments, the therapeutic arena of AA treatments is finally getting more exciting. AA will join the lengthening list of dermatologic diseases with mechanism-targeted drugs, thus changing the face of AA.

Psoriasis in those planning a family, pregnant or breast-feeding. The Australasian Psoriasis Collaboration

The Australasian Psoriasis Collaboration has reviewed the evidence for managing moderate to severe psoriasis in those who are pregnant or are breast-feeding, or planning a family. The severity of the psoriasis, associated comorbidities and specific anti-psoriasis treatment, along with other exposures, can have a deleterious effect on pregnancy outcomes. Psoriasis itself increases the risk of preterm and low birthweight babies, along with spontaneous and induced abortions, but no specific birth defects have been otherwise demonstrated. The baseline risk for a live born baby to have a major birth defect is 3%, and significant neuro-developmental problem is 5%. In Australia, pregnant women with psoriasis are more likely to be overweight or obese, depressed, or smoke in their first trimester, and are also less likely to take prenatal vitamins or supplements. Preconception counselling to improve maternal, pregnancy and baby health is therefore strongly encouraged. The topical and systemic therapies commonly used in psoriasis are each discussed separately, with regards to pregnancy exposure, breast-feeding and effects on male fertility and mutagenicity. The systemic therapies included are acitretin, adalimumab, apremilast, certolizumab, ciclosporin, etanercept, infliximab, ixekizumab, methotrexate, NBUVB, prednisone, PUVA, secukinumab and ustekinumab. The topical therapies include dithranol (anthralin), calcipotriol, coal tar, corticosteroids (weak, potent and super-potent), moisturisers, salicylic acid, tacrolimus, and tazarotene. As a general recommendation, effective drugs that have been widely used for years are preferable to newer alternatives with less foetal safety data. It is equally important to evaluate the risks of not treating, as severe untreated disease may negatively impact both mother and the foetus.

Cutting Edge: Selective Oral ROCK2 Inhibitor Reduces Clinical Scores in Patients with Psoriasis Vulgaris and Normalizes Skin Pathology via Concurrent Regulation of IL-17 and IL-10

Targeted inhibition of Rho-associated kinase (ROCK)2 downregulates the proinflammatory T cell response while increasing the regulatory arm of the immune response in animals models of autoimmunity and Th17-skewing human cell culture in vitro. In this study, we report that oral administration of a selective ROCK2 inhibitor, KD025, reduces psoriasis area and severity index scores by 50% from baseline in 46% of patients with psoriasis vulgaris, and it decreases epidermal thickness as well as T cell infiltration in the skin. We observed significant reductions of IL-17 and IL-23, but not IL-6 and TNF-α, whereas IL-10 levels were increased in peripheral blood of clinical responders after 12 wk of treatment with KD025. Collectively, these data demonstrate that an orally available selective ROCK2 inhibitor downregulates the Th17-driven autoimmune response and improved clinical symptoms in psoriatic patients via a defined molecular mechanism that involves concurrent modulation of cytokines without deleterious impact on the rest of the immune system.

Role and Function of A2A and A₃ Adenosine Receptors in Patients with Ankylosing Spondylitis, Psoriatic Arthritis and Rheumatoid Arthritis

Rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA) are chronic inflammatory rheumatic diseases that affect joints, causing debilitating pain and disability. Adenosine receptors (ARs) play a key role in the mechanism of inflammation, and the activation of A_2A and A₃AR subtypes is often associated with a reduction of the inflammatory status. The aim of this study was to investigate the involvement of ARs in patients suffering from early-RA (ERA), RA, AS and PsA. Messenger RNA (mRNA) analysis and saturation binding experiments indicated an upregulation of A_2A and A₃ARs in lymphocytes obtained from patients when compared with healthy subjects. A_2A and A₃AR agonists inhibited nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) activation and reduced inflammatory cytokines release, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6. Moreover, A_2A and A₃AR activation mediated a reduction of metalloproteinases (MMP)-1 and MMP-3. The effect of the agonists was abrogated by selective antagonists demonstrating the direct involvement of these receptor subtypes. Taken together, these data confirmed the involvement of ARs in chronic autoimmune rheumatic diseases highlighting the possibility to exploit A_2A and A₃ARs as therapeutic targets, with the aim to limit the inflammatory responses usually associated with RA, AS and PsA.

East Indian Sandalwood Oil (EISO) Alleviates Inflammatory and Proliferative Pathologies of Psoriasis

Psoriasis, a chronic inflammatory skin disease marked by hyper proliferation and aberrant differentiation of keratinocytes, affects 2–3% of the world’s population. Research into the pathogenesis of psoriasis has been hampered by the lack of models that accurately reflect the biology of the psoriatic phenotype. We have previously reported that East Indian Sandalwood oil (EISO) has significant anti-inflammatory properties in skin models and hypothesized that EISO might provide therapeutic benefit to psoriasis patients due to its anti-inflammatory and anti-proliferative properties. Here we present interim results from an on-going proof-of-concept Phase 2 clinical trial in which topically applied EISO is demonstrating to be well tolerated and helpful in alleviating mild to moderate psoriasis symptoms. This led us to evaluate the ability of EISO to affect the psoriatic phenotype using MatTek Corporation reconstituted organotypic psoriatic and normal human skin models. EISO had no impact on the phenotype of the normal skin tissue model, however, EISO treatment of the psoriasis tissue model reverted psoriatic pathology as demonstrated by histologic characterization and expression of keratinocyte proliferation markers, Ki67 and psoriasin. These phenotypic affects correlated with suppressed production of ENA-78, IL-6, IL-8, MCP-1, GM-CSF, and IL-1β. Demonstration of the ability of EISO to abrogate these psoriasis symptoms in well-characterized in vitro psoriatic tissue models, supports the hypothesis that the clinically observed symptom alleviation is due to suppression of intrinsic tissue inflammation reactions in afflicted lesions. This study presents a systematic approach to further study the underlying mechanisms that cause psoriasis, and presents data supporting the potential of EISO as a new ethnobotanical therapeutic concept to help direct and accelerate the development of more effective therapies.

[Pathogenesis of psoriasis]

Psoriasis is an inflammatory T cell-mediated autoimmune disease of skin and joints that affects 2-4 % of the adult population and 0.1-1 % of children. Genetic susceptibility, environmental triggering factors, and innate immune processes initiate psoriasis pathogenesis that results in an adaptive autoreactive response. The T cell response is orchestrated by CD 8(+) T cells in the epidermis and by CD 4(+) T cells in the dermis that predominantly produce interleukin-17 (IL‑17). Research of the past 15 years unraveled cellular and molecular mechanisms as well as cytokines like TNF-α or IL‑23 that contribute to psoriatic inflammation. This knowledge has been translated into clinical practice and a number of antipsoriatic small molecules and immunobiologics are now available. Here, we discuss the current principles of psoriasis pathogenesis in the context of modern therapies.

Review of the treatment of psoriatic arthritis with biological agents: choice of drug for initial therapy and switch therapy for non-responders

Psoriatic arthritis (PsA) is a heterogeneous chronic inflammatory disease with a broad clinical spectrum and variable course. It can involve musculoskeletal structures as well as skin, nails, eyes, and gut. The management of PsA has changed tremendously in the last decade, thanks to an earlier diagnosis, an advancement in pharmacological therapies, and a wider application of a multidisciplinary approach. The commercialization of tumor necrosis factor inhibitors (adalimumab, certolizumab pegol, etanercept, golimumab, and infliximab) as well as interleukin (IL)-12/23 (ustekinumab) and IL-17 (secukinumab) inhibitors is representative of a revolution in the treatment of PsA. No evidence-based strategies are currently available for guiding the rheumatologist to prescribe biological drugs. Several international and national recommendation sets are currently available with the aim to help rheumatologists in everyday clinical practice management of PsA patients treated with biological therapy. Since no specific biological agent has been demonstrated to be more effective than others, the drug choice should be made according to the available safety data, the presence of extra-articular manifestations, the patient’s preferences (e.g., administration route), and the drug price. However, future studies directly comparing different biological drugs and assessing the efficacy of treatment strategies specific for PsA are urgently needed.

Managing Scalp Psoriasis: An Evidence-Based Review

BACKGROUND

Scalp psoriasis is commonly the initial presentation of psoriasis, and almost 80 % of patients with psoriasis will eventually experience it.

OBJECTIVE

Although several systematic reviews and guidelines exist, an up-to-date evidence-based review including more recent progress on the use of biologics and new oral small molecules was timely.

METHODS

Of the 475 studies initially retrieved from PubMed and the 845 from Embase (up to May 2016), this review includes 27 clinical trials, four papers reporting pooled analyses of other clinical trials, ten open-label trials, one case series, and two case reports after excluding non-English literature.

RESULTS

To our knowledge, few randomized controlled trials (RCTs) are conducted specifically in scalp psoriasis. Topical corticosteroids provide good effects and are usually recommended as first-line treatment. Calcipotriol-betamethasone dipropionate is well tolerated and more effective than either of its individual components. Localized phototherapy is better than generalized phototherapy on hair-bearing areas. Methotrexate, cyclosporine, fumaric acid esters, and acitretin are well-recognized agents in the treatment of psoriasis, but we found no published RCTs evaluating these agents specifically in scalp psoriasis. Biologics and new small-molecule agents show excellent effects on scalp psoriasis, but the high cost of these treatments mean they may be limited to use in extensive scalp psoriasis.

CONCLUSIONS

More controlled studies are needed for an evidence-based approach to scalp psoriasis.

Apremilast in the treatment of psoriatic arthritis: a perspective review

Apremilast is an orally-active small molecule which inhibits phosphodiesterase-4 (PDE4). Clinical trials have demonstrated its efficacy and safety in psoriatic arthritis (PsA) and psoriasis. Established therapeutic options have variable effectiveness across the different domains of psoriatic disease. Whilst biologic therapies have proven to be of significant benefit to many patients, not all patients respond, and others are not eligible or do not tolerate biologic therapy. We review the mechanism of action, pharmacokinetics and clinical trial data with regards to both efficacy and safety for apremilast and consider where this new treatment may be positioned in the treatment of PsA.

The efficacy and safety of apremilast, etanercept and placebo in patients with moderate-to-severe plaque psoriasis: 52-week results from a phase IIIb, randomized, placebo-controlled trial (LIBERATE)

Background

Apremilast, an oral, small‐molecule phosphodiesterase 4 inhibitor, has demonstrated efficacy in patients with moderate‐to‐severe psoriasis.

Objective

Evaluate efficacy and safety of apremilast vs. placebo in biologic‐naive patients with moderate‐to‐severe plaque psoriasis and safety of switching from etanercept to apremilast in a phase IIIb, randomized, double‐blind, placebo‐controlled study (NCT01690299).

Methods

Two hundred and fifty patients were randomized to placebo (n = 84), apremilast 30 mg BID (n = 83) or etanercept 50 mg QW (n = 83) through Week 16; thereafter, all patients continued or switched to apremilast through Week 104. The primary efficacy endpoint was achievement of PASI‐75 at Week 16 with apremilast vs. placebo. Secondary endpoints included achievement of PASI‐75 at Week 16 with etanercept vs. placebo and improvements in other clinical endpoints vs. placebo at Week 16. Outcomes were assessed through Week 52. This study was not designed for apremilast vs. etanercept comparisons.

Results

At Week 16, PASI‐75 achievement was greater with apremilast (39.8%) vs. placebo (11.9%; P < 0.0001); 48.2% of patients achieved PASI‐75 with etanercept (P < 0.0001 vs. placebo). PASI‐75 response was maintained in 47.3% (apremilast/apremilast), 49.4% (etanercept/apremilast) and 47.9% (placebo/apremilast) of patients at Week 52. Most common adverse events (≥5%) with apremilast, including nausea, diarrhoea, upper respiratory tract infection, nasopharyngitis, tension headache and headache, were mild or moderate in severity; diarrhoea and nausea generally resolved in the first month. No new safety or tolerability issues were observed through Week 52 with apremilast.

Conclusion

Apremilast demonstrated significant efficacy vs. placebo at Week 16 in biologic‐naive patients with psoriasis, which was sustained over 52 weeks, and demonstrated safety consistent with the known safety profile of apremilast. Switching from etanercept to apremilast did not result in any new or clinically significant safety findings, and efficacy was maintained with apremilast through Week 52.

A new therapeutic for the treatment of moderate-to-severe plaque psoriasis: apremilast

Psoriasis is a common, chronic, inflammatory skin disease. Being a life-long condition, a prolonged and safe control of the disease is needed. Current anti-psoriatic treatments show some limits in terms of tolerability and route of administration. Recently, a new oral small molecule, apremilast, has been approved for the treatment of patients with moderate-to-severe plaque psoriasis. Apremilast is a phosphodiesterase 4 (PDE4) inhibitor that regulates the transduction of intracellular signals, including pro-inflammatory and anti-inflammatory pathways. Because of the favorable safety profile and the oral route of administration, apremilast may represent a promising therapeutic target for moderate-to-severe psoriasis. In this review, we report an updated overview about clinical trials testing apremilast in the treatment of psoriasis and seek to provide comprehensive information about this anti-psoriatic drug and a future perspective of the therapeutic algorithm for psoriasis.

Neurological and Neuropsychiatric Adverse Effects of Dermatologic Medications

Severe, recalcitrant dermatologic conditions often require systemic treatment. Although efficacious, these medications have been associated with wide-ranging adverse reactions. Some are reversible, predictable, and either dose-dependent or treatment length-dependent, while others are unpredictable, irreversible, and potentially fatal. This review examines the neuropsychiatric adverse effects associated with US FDA-approved medications for treatment of the following dermatologic pathologies that typically require systemic therapy: autoimmune dermatoses, acne, psoriasis, and melanoma. A search of the literature was performed, with adverse effects ranging from mild headaches and neuropathy to severe encephalopathies. The medications associated with the most serious reactions were those used to treat psoriasis, especially the older non-biologic medications such as cyclosporine A and methotrexate. Given the importance of these systemic dermatologic therapies in treating severe, recalcitrant conditions, and the wide variety of potentially serious neuropsychiatric adverse effects of these medications, neurologists, psychiatrists, dermatologists, oncologists, and primary care providers must be aware of the potential for these neuropsychiatric adverse reactions to allow for appropriate counseling, management, and medication withdrawal.

Apremilast, an oral phosphodiesterase 4 (PDE4) inhibitor: A novel treatment option for nurse practitioners treating patients with psoriatic disease

BACKGROUND AND PURPOSE

Apremilast is an oral nonbiologic medication approved for the treatment of adult patients with active psoriatic arthritis and for patients with moderate to severe plaque psoriasis. This article summarizes the efficacy and safety of apremilast and provides characterization of the novel medication with clinical perspectives to successfully incorporate this therapy into practice for appropriate patients.

DATA SOURCES

A review and synthesis of the results from the ESTEEM (Efficacy and Safety Trial Evaluating the Effects of Apremilast in Psoriasis) phase 3 clinical studies evaluating the efficacy, safety, and tolerability of apremilast for the treatment of moderate to severe plaque psoriasis was conducted.

CONCLUSIONS

Results from the ESTEEM clinical trial program demonstrate that apremilast significantly reduces the severity of moderate to severe plaque psoriasis, has an acceptable safety profile, and is generally well tolerated.

IMPLICATIONS FOR PRACTICE

The novel mechanism of action, convenience of oral administration, and acceptable side effect profile make this medication an attractive choice for clinicians treating patients with plaque psoriasis.

Psoriasis

Psoriasis is a chronic, immune-mediated disorder with cutaneous and systemic manifestations and substantial negative effects on patient quality of life. Psoriasis has a strong, albeit polygenic, genetic basis. Whereas approximately half of the accountable genetic effect of psoriasis maps to the major histocompatibility complex, >70 other loci have been identified, many of which implicate nuclear factor-κB, interferon signalling and the IL-23-IL-23 receptor axis. Psoriasis pathophysiology is characterized by abnormal keratinocyte proliferation and immune cell infiltration in the dermis and epidermis involving the innate and adaptive immune systems, with important roles for dendritic cells and T cells, among other cells. Frequent comorbidities are rheumatological and cardiovascular in nature, in particular, psoriatic arthritis. Current treatments for psoriasis include topical agents, photo-based therapies, traditional systemic drugs and biologic agents. Treatments can be used in combination or as monotherapy. Biologic therapies that target specific disease mediators have become a mainstay in the treatment of moderate-to-severe disease, whereas advances in the treatment of mild-to-moderate disease have been limited.

Worsening of Lymphopenia during Apremilast Treatment

Apremilast is an oral phosphodiesterase IV inhibitor recently registered for the treatment of psoriasis and psoriatic arthritis in Switzerland and other countries. Even though it offers only moderate efficacy compared to biologics, many patients prefer drugs given by the oral route. Apremilast is frequently used in private practice, as it showed no relevant safety signals in clinical trials and often, laboratory tests are omitted completely. Here we report a patient who developed acute lymphopenia and worsening of psoriasis during apremilast treatment, which resolved with discontinuation of apremilast. We suggest that at least in prospective registries, that regular monitoring of laboratory surrogate markers should be performed on a long-term basis to detect rare but potentially important safety signals.

Selective Phosphodiesterase Inhibitors for Psoriasis: Focus on Apremilast

Phosphodiesterase (PDE) 4 participates in regulating the inflammatory response by degrading cyclic adenosine 3′,5′-monophosphate (cAMP), a key second messenger. Inhibition of PDE4 increases the intracellular cAMP level, which in turn results in a reduction in inflammatory mediators and an increase in anti-inflammatory mediators. Immune-modulating effects of PDE4 inhibitors have been investigated in a number of inflammatory conditions, such as asthma, atopic dermatitis, chronic obstructive pulmonary disease, Behçet’s disease, psoriasis, and psoriatic arthritis. Apremilast, a selective PDE4 inhibitor, has been shown to block the production of pro-inflammatory cytokines (interferon-γ, tumor necrosis factor-α, interleukin [IL]-12, IL-17, and IL-23), which are the key players in the pathogenesis of psoriasis. Increased intracellular cAMP levels result in a range of anti-inflammatory effects on numerous cell lines. A decrease in pro-inflammatory activity has been shown to result in a reduced psoriasiform response in preclinical in vivo models of psoriasis, and reduction of biologic activity in a pilot study in humans. The efficacy and safety of apremilast in the treatment of psoriasis have been demonstrated in phase II and III clinical trials. Apremilast demonstrated efficacy in reducing the severity of moderate to severe plaque psoriasis. Treatment with apremilast was well tolerated, with generally mild gastrointestinal complaints, which occurred early in the course of the treatment and resolved over time, and there was no requirement for laboratory test monitoring. These results make apremilast an attractive therapeutic option for plaque psoriasis.

The effects of apremilast on the QTc interval in healthy male volunteers: a formal, thorough QT study

OBJECTIVE

This study was conducted to evaluate the effect of apremilast and its major metabolites on the placebocorrected change-from-baseline QTc interval of an electrocardiogram (ECG).

MATERIALS AND METHODS

Healthy male subjects received each of 4 treatments in a randomized, crossover manner. In the 2 active treatment periods, apremilast 30 mg (therapeutic exposure) or 50 mg (supratherapeutic exposure) was administered twice daily for 9 doses. A placebo control was used to ensure doubleblind treatment of apremilast, and an openlabel, single dose of moxifloxacin 400 mg was administered as a positive control. ECGs were measured using 24-hour digital Holter monitoring.

RESULTS

The two-sided 98% confidence intervals (CIs) for ΔΔQTcI of moxifloxacin completely exceeded 5 ms 2 - 4 hours postdose. For both apremilast dose studies, the least-squares mean ΔΔQTcI was < 1 ms at all time points, and the upper limit of two-sided 90% CIs was < 10 ms. There were no QT/QTc values > 480 ms or a change from baseline > 60 ms. Exploratory evaluation of pharmacokinetic/pharmacodynamic data showed no trend between the changes in QT/QTc interval and the concentration of apremilast or its major metabolites M12 and M14.

CONCLUSIONS

Apremilast did not prolong the QT interval and appears to be safe and well tolerated up to doses of 50 mg twice daily.

Pharmacodynamic assessment of apremilast for the treatment of moderate-to-severe plaque psoriasis

INTRODUCTION

Psoriasis is a chronic inflammatory skin disease affecting 2-3% of the population. Certain systemic drugs currently available for its treatment could be associated, in the long term, with organ toxicity and adverse events, thus, clinical monitoring throughout treatment is required. Moreover, tolerability issues, parenteral administration, and barriers to patient access, such as high cost and specialist management lead to treatment failure.

AREAS COVERED

Apremilast is an oral small molecule inhibitor of phosphodiesterase 4 (PDE4i). PDE is the major enzyme class responsible for the hydrolysis of cyclic adenosine monophosphate in immune cells (cAMP). With PDE4 inhibition, apremilast works intracellularly to modulate pro-inflammatory and anti-inflammatory mediator production critically involved in psoriasis. The aim of this paper is to focus the attention on apremilast pharmacodynamics effects, its efficacy and safety in treating moderate-to-severe plaque psoriasis.

EXPERT OPINION

Apremilast is an effective and well-tolerated option in treating moderate-to-severe plaque psoriasis. Its safety profile and the oral administration offer significant advantages in prescribing apremilast for the treatment of psoriasis, particularly in some subsets of patients.

Determination of apremilast in rat plasma by UPLC–MS/MS in ESI-negative mode to avoid adduct ions formation

Background: Quantification of target analyte by LC–MS/MS is sometimes hampering due to competitive adduct ions formation (sodium and/or ammonium) in positive ionization mode. A UPLC–MS/MS assay was developed for the determination of apremilast in rat plasma using ESI-negative mode to avoid adduct ions formation. Method & results: After extraction from plasma by ethyl acetate, analyte and IS were separated on Aquity BEH C18 column using acetonitrile-10 mM ammonium acetate (85:15) as mobile phase. The calibration curve was linear between 3.04 and 1000 ng/ml with correlation coefficients (r2) of ≥0.995 and lower limit of quantification of 3.04 ng/ml. All validation parameter results were within the acceptable range. The assay was successfully employed in oral PK study with Cmax of 584.29 ng/ml and AUC0–20 of 6530 ng.h/ml after apremilast (2 mg/kg) administration. Conclusion: This result suggests that ESI in negative mode would be an alternative approach for LC–MS/MS quantification of analytes, which produce competitive adducts in positive mode.

Molecular Mechanisms for cAMP-Mediated Immunoregulation in T cells - Role of Anchored Protein Kinase A Signaling Units

The cyclic AMP/protein kinase A (cAMP/PKA) pathway is one of the most common and versatile signal pathways in eukaryotic cells. A-kinase anchoring proteins (AKAPs) target PKA to specific substrates and distinct subcellular compartments providing spatial and temporal specificity for mediation of biological effects channeled through the cAMP/PKA pathway. In the immune system, cAMP is a potent negative regulator of T cell receptor-mediated activation of effector T cells (Teff) acting through a proximal PKA/Csk/Lck pathway anchored via a scaffold consisting of the AKAP Ezrin holding PKA, the linker protein EBP50, and the anchoring protein phosphoprotein associated with glycosphingolipid-enriched microdomains holding Csk. As PKA activates Csk and Csk inhibits Lck, this pathway in response to cAMP shuts down proximal T cell activation. This immunomodulating pathway in Teff mediates clinically important responses to regulatory T cell (Treg) suppression and inflammatory mediators, such as prostaglandins (PGs), adrenergic stimuli, adenosine, and a number of other ligands. A major inducer of T cell cAMP levels is PG E2 (PGE2) acting through EP2 and EP4 prostanoid receptors. PGE2 plays a crucial role in the normal physiological control of immune homeostasis as well as in inflammation and cancer immune evasion. Peripherally induced Tregs express cyclooxygenase-2, secrete PGE2, and elicit the immunosuppressive cAMP pathway in Teff as one tumor immune evasion mechanism. Moreover, a cAMP increase can also be induced by indirect mechanisms, such as intercellular transfer between T cells. Indeed, Treg, known to have elevated levels of intracellular cAMP, may mediate their suppressive function by transferring cAMP to Teff through gap junctions, which we speculate could also be regulated by PKA/AKAP complexes. In this review, we present an updated overview on the influence of cAMP-mediated immunoregulatory mechanisms acting through localized cAMP signaling and the therapeutical increasing prospects of AKAPs disruptors in T-cell immune function.

Apremilast, an oral phosphodiesterase 4 inhibitor, in patients with psoriatic arthritis and current skin involvement: a phase III, randomised, controlled trial (PALACE 3)

OBJECTIVE

To evaluate apremilast treatment in patients with active psoriatic arthritis, including current skin involvement, despite prior therapy with conventional disease-modifying antirheumatic drugs and/or biologic agents.

METHODS

Patients (N=505) were randomised (1:1:1) to placebo, apremilast 20 mg twice daily, or apremilast 30 mg twice daily. Rescue therapy with apremilast was designated at week 16 for placebo patients not achieving 20% improvement in swollen and tender joint counts. At week 24, the remaining placebo patients were then randomised to apremilast 20 mg twice daily or 30 mg twice daily. The efficacy and safety of apremilast were assessed over 52 weeks.

RESULTS

At week 16, significantly more patients receiving apremilast 20 mg twice daily (28%) and 30 mg twice daily (41%) achieved 20% improvement in American College of Rheumatology response criteria versus placebo (18%; p=0.0295 and p<0.0001, respectively), and mean decrease in the Health Assessment Questionnaire-Disability Index score was significantly greater with apremilast 30 mg twice daily (-0.20) versus placebo (-0.07; p=0.0073). In patients with baseline psoriasis body surface area involvement ≥3%, significantly more apremilast 30 mg twice daily patients achieved 50% reduction from baseline Psoriasis Area and Severity Index score (41%) versus placebo (24%; p=0.0098) at week 16. At week 52, observed improvements in these measures demonstrated sustained response with continued apremilast treatment. Most adverse events were mild to moderate in severity; the most common were diarrhoea, nausea, headache and upper respiratory tract infection.

CONCLUSIONS

Apremilast demonstrated clinically meaningful improvements in psoriatic arthritis and psoriasis at week 16; sustained improvements were seen with continued treatment through 52 weeks. Apremilast was generally well tolerated and demonstrated an acceptable safety profile.

TRIAL REGISTRATION NUMBER

NCT01212770.

Impact of Renal Impairment on the Pharmacokinetics of Apremilast and Metabolite M12

The pharmacokinetics of apremilast and its major metabolite M12 were evaluated in subjects with varying degrees of renal impairment. Men and women with renal impairment (estimated glomerular filtration rate, 60‒89 mL/min [mild, n = 8], 30‒59 mL/min [moderate, n = 8], or <30 mL/min [severe, n = 8]) or demographically healthy matched (control) subjects (n = 24) received a single oral dose of apremilast 30 mg. Plasma apremilast and metabolite M12 concentrations were determined, and pharmacokinetic parameters were calculated from samples obtained predose and up to 72 hours postdose. In subjects with mild to moderate renal impairment, apremilast pharmacokinetic profiles were similar to healthy matched subjects. In subjects with severe renal impairment, apremilast elimination was significantly slower, and exposures based on area under the plasma concentration‐versus‐time curve from time zero extrapolated to infinity and maximum observed plasma concentration were increased versus healthy matched subjects. Metabolite M12 pharmacokinetic profiles for subjects with mild renal impairment were similar to those of the healthy matched subjects; however, they were increased in both the moderate and severe renally impaired subjects. Dose reduction of apremilast is recommended in individuals with severe renal impairment, but not in those with mild to moderate renal impairment.

New therapies for psoriasis and psoriatic arthritis

PURPOSE OF REVIEW

Over the last several years, novel immunologic pathways pivotal in the development of the pathobiology of psoriasis and psoriatic arthritis (PsA) have been revealed. These discoveries catalyzed a search for new treatment targets resulting in many new therapies that are now available for patients with psoriatic disease.

RECENT FINDINGS

Helper T cells that secrete interleukin-17 (TH17) along with CD8+ cells, innate lymphocyte cells, and gamma delta T cells are important in the pathogenesis of psoriasis and PsA. Recently, agents that target interleukin-17, the interleukin-17 receptor, and interleukin-23 (antip19) have been approved or are in clinical trials. Apremilast, a new oral agent, was approved for the treatment of psoriasis and PsA.

SUMMARY

Secukinumab, an interleukin-17A antibody, has been approved for treatment of psoriasis and PsA in the United States. It is effective with a good safety profile. Ixekizumab, another anti-interleukin-17A antibody, is currently in clinical trials and brodalumab, an interleukin-17 receptor antagonist, was removed from clinical trials because of safety concerns despite demonstrated efficacy in psoriasis and PsA. Targeting interleukin-23 with antibodies to p19 is another approach with encouraging results in psoriasis. Apremilast, an oral agent, approved to treat psoriasis and PsA demonstrates moderate efficacy with an excellent safety record. The role of tofacitinib in psoriatic disease remains to be determined pending a safety review in psoriasis and completion of PsA trials.

Novel treatment options for juvenile idiopathic arthritis

The purpose of this review is to summarize the newer and possible future treatments for the arthritis and systemic features in children with juvenile idiopathic arthritis (JIA), including evidence supporting their efficacy and safety.

Difficult-To-Treat Juvenile Idiopathic Arthritis: Current and Future Options

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease in childhood and is usually treated with non-steroidal anti-inflammatory drugs or disease-modifying anti-rheumatic drugs (DMARDs) such as methotrexate or sulfasalazine. However, not all patients respond to these treatments, and toxicities may limit long-term use or diminish compliance. With advances in pharmacotherapy and the development of new therapeutic agents, there have been improvements in treatment of both systemic and non-systemic JIA, particularly with biologic agents such as anti-tumor necrosis factor (TNF)-α, anti-interleukin (IL)-1, and anti-IL6. Anti-cell therapies, such as co-stimulator blockers or anti-CD20, small molecules, and biosimilars represent new areas of interest, and, while many are not yet currently commercially available for use in children, preliminary studies appear to be promising. In the present article, the authors review therapeutic strategies for the different JIA subtypes, mainly according to guidelines and recommendations. Newer and possible future treatments for arthritis, already approved in adults but currently under study in children, are also discussed. Drugs currently in development plans for rheumatoid arthritis, which hopefully will also be useful for JIA patients in the future, are also mentioned in this paper.

Papaverine inhibits lipopolysaccharide-induced microglial activation by suppressing NF-κB signaling pathway

Objective

To investigate the effects of papaverine (PAP) on lipopolysaccharide (LPS)-induced microglial activation and its possible mechanisms.

Materials and methods

BV2 microglial cells were first pretreated with PAP (0, 0.4, 2, 10, and 50 μg/mL) and then received LPS stimulation. Transcription and production of proinflammatory factors (IL1β, TNFα, iNOS, and COX-2) were used to evaluate microglial activation. The transcriptional changes undergone by M1/M2a/M2b markers were used to evaluate phenotype transformation of BV2 cells. Immunofluorescent staining and Western blot were used to detect the location and expression of P65 and p-IKK in the presence or absence of PAP pretreatment.

Results

Pretreatment with PAP significantly inhibited the expression of IL1β and TNFα, and suppressed the transcription of M1/M2b markers Il1rn, Socs3, Nos2 and Ptgs2, but upregulated the transcription of M2a markers (Arg1 and Mrc1) in a dose-dependent manner. In addition, PAP pretreatment significantly decreased the expression of p-IKK and inhibited the nuclear translocation of P65 after LPS stimulation.

Conclusion

PAP not only suppressed the LPS-induced microglial activity by inhibiting transcription/production of proinflammatory factors, but also promoted the transformation of activated BV2 cells from cytotoxic phenotypes (M1/M2b) to a neuroprotective phenotype (M2a). These effects were probably mediated by NF-κB signaling pathway. Thus, it would be a promising candidate for the treatment of neurodegenerative diseases.

Emerging drugs for psoriatic arthritis

INTRODUCTION

The majority of Psoriatic Arthritis patients experience a good clinical response to anti-Tumor Necrosis Factor (TNF)-α therapies. However, treatment failure with anti-TNF-α can represent a relevant clinical problem.

AREAS COVERED

We review the efficacy and safety profile of biological therapies that have been reported from randomized, controlled trials in phase II and phase III available in Pubmed Database for agents targeting IL-12/23p40 antibody (ustekinumab) and IL-17 (secukinumab), inhibitor of phosphodiesterase 4, (apremilast), and of JAK/STAT pathways (tofacitinib) and CTLA4 co-stimulation (abatacept) in Psoriatic Arthritis.

EXPERT OPINION

In Psoriatic Arthritis, main emerging drugs are represented by the fully human monoclonal IL-12/23p40 antibody, ustekinumab, the agent targeting IL-17, secukinumab, and the inhibitor of phosphodiesterase 4, apremilast. Results on T cell co-stimulation inhibition by abatacept are insufficient both in psoriasis and in PsA. In vitro investigations on JAK/STAT pathways in PsA suggest that tofacitinib could represent a further valuable therapeutic option. Emerging biological treatments other than anti-TNF agents, ustekinumab, secukinumab and apremilast appear promising for Psoriatic Arthritis and recent studies have showed a good efficacy and an acceptable safety profile; however, further and long-term studies are advocated.

Apremilast: A Novel Drug for Treatment of Psoriasis and Psoriatic Arthritis

OBJECTIVE

To review the pharmacology, efficacy, and safety of apremilast and determine its role relative to other agents in the treatment of psoriasis and psoriatic arthritis.

DATA SOURCES

A PubMed search (1946 to December 2015) using the terms apremilast and CC-10004 was conducted to identify relevant articles.

STUDY SELECTION AND DATA EXTRACTION

In vitro or in vivo evaluations of apremilast published in the English language were eligible for inclusion. Controlled clinical trials that involved psoriasis or psoriatic arthritis were selected for review.

DATA SYNTHESIS

Four trials were identified on the treatment of psoriasis. In those that involved doses of 30 mg twice daily, a significantly greater percentage of patients receiving apremilast (28.8% to 40.9%) compared with placebo (5.3% to 5.8%) achieved at least 75% improvement from baseline in Psoriasis Area and Severity Index score at 16 weeks. Two trials were identified on the treatment of psoriatic arthritis. In the one that involved a dose of 30 mg twice daily, a significantly greater percentage of patients receiving apremilast (38.1%) compared with placebo (19.0%) achieved the American College of Rheumatology criteria for 20% improvement at 16 weeks. In all trials, the drug had an acceptable safety profile, with the most common adverse effects of diarrhea, nausea, and headache.

CONCLUSIONS

Apremilast has a novel mechanism of action and is safe and effective for the management of psoriasis and psoriatic arthritis. At this time, apremilast should be reserved for patients unable to take disease-modifying antirheumatic drugs.

Anti-TNF agents for paediatric psoriasis

BACKGROUND

Psoriasis is a chronic skin disease that may develop at any age. Estimates for the United States and Europe suggest that psoriasis accounts for 4% of skin diseases in children. In most cases, the condition is mild and can be treated with creams. However, a small percentage of children have moderate to severe disease that requires drugs, such as ciclosporin or methotrexate, and some will require injections with newer biological agents, such as anti-TNF (tumour necrosis factor) drugs. Anti-TNF drugs (among them etanercept, infliximab, and adalimumab) are designed to reduce inflammation in the body caused by tumour necrosis factor. Evidence for the safety and efficacy of these biological agents in paediatric psoriasis is lacking.

OBJECTIVES

To assess the efficacy and safety of anti-TNF agents for the treatment of paediatric psoriasis.

SEARCH METHODS

We searched the following databases up to July 2015: the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 6), MEDLINE (from 1946), Embase (from 1974), and LILACS (from 1982). We also searched 13 trials registers and checked the reference lists of included studies and key review articles for further references to relevant randomised controlled trials (RCTs). We handsearched conference proceedings and attempted to contact trial authors and relevant pharmaceutical manufacturers. We searched the US Food and Drug Administration's and European Medicines Agency's adverse effects databases.

SELECTION CRITERIA

All relevant RCTs that evaluated the efficacy and safety of anti-TNF agents for the treatment of chronic plaque psoriasis in individuals less than 18 years of age.

DATA COLLECTION AND ANALYSIS

Two review authors independently checked titles and abstracts and performed data extraction and 'Risk of bias' assessment of the included studies. One review author entered data into Review Manager (RevMan), and a second review author checked the data. We also attempted to obtain unclear data from the trial authors where possible.Our primary outcomes were investigator-assessed number of participants achieving a 75% improvement in Psoriasis Area and Severity Index-75 (PASI 75) compared to baseline, improvement in quality of life using an instrument such as Children's Dermatology Life Quality Index (CDLQI), and adverse effects. Our secondary outcomes included the proportion of participants achieving PASI 50 and the Physician's Global Assessment (PGA).

MAIN RESULTS

We included one study with 211 participants (median age 13 years), in which etanercept (dosage ranged from 0.8 to 50 mg per kilogram of body weight) was compared to placebo. Follow-up was over a 48-week period.At week 12, 57% versus 11% who received etanercept or placebo, respectively, achieved the PASI 75 (risk ratio 4.95, 95% confidence interval (CI) 2.83 to 8.65; high-quality evidence). Absolute risk reduction and the number needed to treat to obtain a benefit with etanercept was 45% (95% CI 33.95 to 56.40) and 2 (95% CI 1.77 to 2.95), respectively.The percentage improvement from baseline of the CDLQI scores at week 12 was better in the etanercept group than the placebo group (52.3% versus 17.5%, respectively (P = 0.0001)). Analysis between the groups showed an effect size that was clinically important (mean difference 2.30, 95% CI 0.85 to 3.75; high-quality evidence). However, means, medians, and minimal important difference results and results of the Pediatric Quality of Life Inventory, Stein Impact on Family Scale, and Harter Self-Perception Profile for Children scores must be interpreted with caution, as they were not prespecified outcomes.Three serious adverse events were reported, but they were resolved without sequelae. Deaths or other events such as malignant tumours, opportunistic infections, tuberculosis, or demyelination were not reported in the included study.Also, 13% of participants in the placebo group and 53% in the etanercept group had a PGA of clear or almost clear (risk ratio 3.96, 95% CI 2.36 to 6.66; high-quality evidence) at week 12.

AUTHORS' CONCLUSIONS

This review found only one RCT evaluating the use of this type of biological therapy. Although the risk of publication bias was high, as we included only one industry-sponsored RCT, the risk of allocation, selection, performance, attrition, and selective reporting biases for all outcomes (except for CDLQI) was low, and no short-term serious adverse events were found.We can conclude, based on this single included study, that etanercept seems to be efficacious and safe (at least in the short term) for the treatment of paediatric psoriasis. However, as the GRADE approach refers not to individual studies but to a body of evidence, we shall wait for the results of the ongoing studies in a future update of this review. In addition, future studies should evaluate quality-of-life endpoints established a priori and standardise primary outcome measures such as PASI 75, and should include the PGA as a secondary endpoint. Also, collating and reporting adverse events uniformly is required to better evaluate safety.

Update on psoriasis immunopathogenesis and targeted immunotherapy

Over recent years, significant progress has been made in characterisation of the underlying pathogenic mechanisms in psoriasis, a common cutaneous disease that is associated with major systemic co-morbidity and reduced life expectancy. Basic science discoveries have informed the design of novel therapeutic approaches, many of which are now under evaluation in late-stage clinical trials. Here we describe the complex interplay between immune cell types and cytokine networks that acts within self-perpetuating feedback loops to drive cutaneous inflammation in psoriasis. Genetic studies have been pivotal in the construction of the disease model and more recently have uncovered a distinct aetiology for rare, pustular variants of psoriasis. The translation of mechanistic insights into potential advancements in clinical care will also be described, including several treatments that target the interleukin-23 (IL-23)/T17 immune axis.

The sympathetic nervous response in inflammation

Over the past decades evidence has accumulated clearly demonstrating a pivotal role for the sympathetic nervous system (SNS) and its neurotransmitters in regulating inflammation. The first part of this review provides the reader with an overview showing that the interaction of the SNS with the immune system to control inflammation is strongly context-dependent (for example, depending on the activation state of the immune cell or neuro-transmitter concentration). In the second part we focus on autoimmune arthritis as a well investigated example for sympathetically controlled inflammation to show that the SNS and catecholamines play a differential role depending on the time point of ongoing disease. A model will be developed to explain the proinflammatory effects of the SNS in the early phase and the anti-inflammatory effects of catecholamines in the later phase of autoimmune arthritis. In the final part, a conceptual framework is discussed that shows that a major purpose of increased SNS activity is nourishment of a continuously activated immune system at a systemic level using energy-rich fuels (glucose, amino acids, lipids), while uncoupling from central nervous regulation occurs at sites of inflammation by repulsion of sympathetic fibers and local adrenoceptor regulation. This creates zones of ‘permitted local inflammation’. However, if this ‘inflammatory configuration’ persists and is strong, as in autoimmunity, the effects are detrimental because of the resultant chronic catabolic state, leading to cachexia, high blood pressure, insulin resistance, and increased cardiovascular mortality, and so on. Today, the challenge is to translate this conceptual knowledge into clinical benefit.

New treatment paradigms in psoriatic arthritis: an update on new therapeutics approved by the U.S. Food and Drug Administration

PURPOSE OF REVIEW

The purpose of this study is to give an overview of the new treatments approved by the U.S. Food and Drug Administration (FDA) for use in psoriatic arthritis (PsA).

RECENT FINDINGS

FDA has approved three new drugs for PsA: Certolizumab-pegol: a PEGylated Fc-free tumour necrosis factor inhibitor (TNFi); ustekinumab: an anti interleukin (IL)-12 and IL-23 mAb; and apremilast and oral phosphodiesterase 4 inhibitor. On well designed and extensive developing programmes, all three drugs proved to be effective for the treatment of most PsA manifestations, including peripheral arthritis, skin involvement, enthesitis, dactylitis, quality of life and radiographic progression in patients failing traditional disease modifying drugs (DMARDs) and TNFi. Safety profile of all three drugs seems to be reassuring until now, although long-term data are still not available. Although Certolizumab-pegol is likely to be placed among the other TNFi, ustekinumab and apremilast, due to lower efficacy on arthritis, are being more frequently used as second-line therapy after TNFi failure, especially among rheumatologists.

SUMMARY

There are new therapeutic options approved for the treatment of PsA. For the first time, well proved effective therapies with a different mechanism of action than the inhibition of TNF alpha are available for the treatment of this progressive disease.

Apremilast, an oral phosphodiesterase 4 (PDE4) inhibitor, in patients with moderate to severe plaque psoriasis: Results of a phase III, randomized, controlled trial (Efficacy and Safety Trial Evaluating the Effects of Apremilast in Psoriasis [ESTEEM] 1)

BACKGROUND

Apremilast works intracellularly to regulate inflammatory mediators.

OBJECTIVE

ESTEEM 1 evaluated efficacy/safety of apremilast at 30 mg twice a day for moderate to severe plaque psoriasis.

METHODS

This phase III, multicenter, double-blind, placebo-controlled study randomized adults (2:1) to apremilast or placebo. At week 16, the placebo group switched to apremilast through week 32, followed by a randomized treatment withdrawal phase to week 52. Binary end points were analyzed using χ(2) test; continuous end points used analysis of covariance.

RESULTS

In all, 844 patients were randomized (n = 282, placebo; n = 562, apremilast). At week 16, significantly more patients taking apremilast achieved 75% or greater reduction from baseline Psoriasis Area and Severity Index score (PASI-75) (33.1%) versus placebo (5.3%, P < .0001; primary end point). Most (61.0%) patients rerandomized to apremilast at week 32 achieved PASI-75 at week 52 versus 11.7% rerandomized to placebo. Of patients rerandomized to apremilast at week 32, mean percentage change from baseline PASI score was -88% to -81% (weeks 32-52). During the placebo-controlled period, 55.7% and 69.3% of patients randomized to placebo and apremilast, respectively, had 1 or more adverse events. Most adverse events were mild/moderate in severity. No new significant adverse events emerged with continued apremilast exposure versus the placebo-controlled period.

LIMITATIONS

Data were limited to 52 weeks and may not generalize to nonplaque psoriasis.

CONCLUSIONS

Apremilast was effective in moderate to severe plaque psoriasis.

Alopecia areata profiling shows TH1, TH2, and IL-23 cytokine activation without parallel TH17/TH22 skewing

BACKGROUND

Alopecia areata (AA) is a common T cell-mediated disorder with limited therapeutics. A molecular profile of cytokine pathways in AA tissues is lacking. Although studies have focused on TH1/IFN-γ responses, several observations support a shared genetic background between AA and atopy.

OBJECTIVE

We sought to define the AA scalp transcriptome and associated biomarkers with comparisons with atopic dermatitis (AD) and psoriasis.

METHODS

We performed microarray and RT-PCR profiling of 27 lesional and 17 nonlesional scalp samples from patients with AA for comparison with normal scalp samples (n = 6). AA gene expression was also compared with samples from patients with lesional or nonlesional AD and those with psoriasis. A fold change of greater than 1.5 and a false discovery rate of less than 0.05 were used for differentially expressed genes (DEGs).

RESULTS

We established the AA transcriptomes (lesional vs nonlesional: 734 DEGs [297 upregulated and 437 downregulated]; lesional vs normal: 4230 DEGs [1980 upregulated and 2250 downregulated]), including many upregulated immune and downregulated hair keratin genes. Equally impressive as upregulation in TH1/interferon markers (IFNG and CXCL10/CXCL9) were those noted in TH2 (IL13, CCL18, CCL26, thymic stromal lymphopoietin, and periostin), TH9/IL-9, IL-23 (p40 and p19), and IL-16 mediators (all P < .05). There were no increases in TH17/TH22 markers. Hair keratin (KRT) expressions (ie, KRT86 and KRT85) were significantly suppressed in lesional skin. Greater scalp involvement (>25%) was associated with greater immune and keratin dysregulation and larger abnormalities in nonlesional scalp samples (ie, CXCL10 and KRT85).

CONCLUSIONS

Our data associate the AA signature with TH2, TH1, IL-23, and IL-9/TH9 cytokine activation, suggesting consideration of anti-TH2, anti-TH1, and anti-IL-23 targeting strategies. Similar to psoriasis and AD, clinical trials with selective antagonists are required to dissect key pathogenic pathways.