The pharmacodynamic impact of apremilast, an oral phosphodiesterase 4 inhibitor, on circulating levels of inflammatory biomarkers in patients with psoriatic arthritis: substudy results from a phase III, randomized, placebo-controlled trial (PALACE 1)

PDE4 Inhibition and Inflammatory Bowel Disease: A Novel Therapeutic Avenue

BACKGROUND

In the last few decades, a better knowledge of the inflammatory pathways involved in the pathogenesis of Inflammatory Bowel Disease (IBD) has promoted biological therapy as an important tool to treat IBD patients. However, in spite of a wider spectrum of biological drugs, a significant proportion of patients is unaffected by or lose their response to these compounds, along with increased risks of infections and malignancies. For these reasons there is an urgent need to look for new pharmacological targets. The novel Phosphodiesterase 4 (PDE4) inhibitors have been recently introduced as new modulators of intracellular signals and gene transcription for the treatment of IBD.

AIM

To discuss and describe the state of the art of this new class of compounds in the IBD field, with particular attention to apremilast.

METHODS

Published articles selected from PubMed were comprehensively reviewed, with key words including apremilast, inflammatory disease, IBD, psoriasis, psoriatic arthritis, pathogenesis, therapies, and treatment.

RESULTS

PDE4 inhibitors generate elevated intracellular levels of cyclic Adenosine Monophosphate (cAMP), that consequently down-regulate the release of pro-inflammatory cytokines in the mucosa of IBD patients. The newly developed apremilast is one of these drugs and has already been approved for the treatment of dermatologic/rheumatologic inflammatory conditions; studies in psoriasis and psoriatic arthritis have in fact demonstrated its clinical activity. However, no clinical trials have yet been published on the use of apremilast in IBD.

CONCLUSION

In light of the similarity of pro-inflammatory signaling pathways across the gut, the skin, and joints, apremilast is likely supposed to show its efficacy also in IBD.

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.

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.

Targeted therapies: what they teach us about the pathogenesis of psoriasis and psoriatic arthritis

INTRODUCTION

Biologic therapy has revolutionized treatment pathways in psoriatic joint and skin disease. It has also provided a useful tool with which pathological pathways of this condition may be explored. Areas covered: This review presents data on the clinical and biological effects of targeted therapy in psoriatic arthritis and psoriasis. Therapeutic agents covered include inhibitors of TNFα, inhibitors of the IL-23/IL-17 axis and inhibitors of intracellular small molecules involved in the transduction of the inflammatory signal. Trial data on clinical and imaging efficacy is reviewed in parallel with studies on biological effects at tissue level. Pathological insights gained from the use of these treatments are explored. Expert commentary: A close relationship exists between specific pathological types and clinical manifestations of psoriatic disease, including responses to treatment. Studying these relationships is likely to improve understanding of disease and enable rational selection of specific treatments for patients with specific pathotypes.

New Oral Therapies for Psoriasis: A Comprehensive Review

Conventional oral therapies for psoriasis, including methotrexate, cyclosporine, and acitretin, have generally unfavorable safety profiles and are not ideal for long-standing use. Thus, new oral therapies are necessary for patients with more moderate disease, patients who prefer oral treatments to injectable biologies, and patients who failed conventional therapies. The authors review here the clinical and safety evidence of phosphodiesterase 4 inhibitor, apremilast, janus kinase inhibitors, including tofacitinib, and fumarie acid esters as additional options in oral psoriasis therapy.

A Phase III, Randomized, Controlled Trial of Apremilast in Patients with Psoriatic Arthritis: Results of the PALACE 2 Trial

OBJECTIVE

Apremilast, an oral phosphodiesterase 4 inhibitor, downregulates intracellular inflammatory mediator synthesis by elevating cyclic adenosine monophosphate levels. The PALACE 2 trial evaluated apremilast efficacy and safety in patients with active psoriatic arthritis (PsA) despite prior conventional disease-modifying antirheumatic drugs and/or biologic therapy.

METHODS

Eligible patients were randomized (1:1:1) to placebo, apremilast 20 mg BID, or apremilast 30 mg BID. At Week 16, patients with swollen and tender joint count improvement < 20% entered early escape, with placebo patients rerandomized (1:1) to apremilast 20 mg BID or 30 mg BID while apremilast patients continued on their initial apremilast dose. At Week 24, patients remaining on placebo were rerandomized to apremilast 20 mg BID or 30 mg BID. The primary endpoint was the proportion of patients achieving > 20% improvement in American College of Rheumatology response criteria (ACR20) at Week 16.

RESULTS

In the intent-to-treat population (N = 484), ACR20 at Week 16 was achieved by more patients receiving apremilast 20 mg BID [37.4% (p = 0.0002)] and 30 mg BID [32.1% (p = 0.0060)] versus placebo (18.9%). Clinically meaningful improvements in signs and symptoms of PsA, physical function, and psoriasis were observed with apremilast through Week 52. The most common adverse events were diarrhea, nausea, headache, and upper respiratory tract infection. Diarrhea and nausea generally occurred early and usually resolved spontaneously with continued treatment. Laboratory abnormalities were infrequent and transient.

CONCLUSION

Apremilast demonstrated clinical improvements in PsA for up to 52 weeks, including signs and symptoms, physical function, and psoriasis. No new safety signals were observed. ClinicalTrials.gov identifier: NCT01212757.

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.

Apremilast: A Review in Psoriasis and Psoriatic Arthritis

Apremilast (Otezla(®)) is an oral phosphodiesterase 4 inhibitor indicated for the twice-daily treatment of adults with psoriasis and psoriatic arthritis (PsA). Its use in these patient populations has been assessed in two phase III clinical trial programmes (ESTEEM and PALACE). At 16 weeks in the two ESTEEM trials, apremilast reduced the severity and extent of moderate to severe plaque psoriasis, including nail, scalp and palmoplantar manifestations, versus placebo in adults, with these benefits generally being sustained over 52 weeks of treatment. Similarly, in three PALACE trials (PALACE 1-3), apremilast improved the signs and symptoms of PsA relative to placebo at 16 weeks in adults with active disease despite treatment with conventional synthetic and/or biologic disease-modifying anti-rheumatic drugs. These PsA benefits were generally sustained for up to 104 weeks of treatment; skin involvement, enthesitis and dactylitis also improved with the drug. Apremilast was generally well tolerated, with the most common adverse events being diarrhoea and nausea in the first year of treatment (usually occurring in the first 2 weeks after the first dose and resolving within 4 weeks) and nasopharyngitis and upper respiratory tract infection with continued treatment. Although further longer-term and comparative efficacy and tolerability data would be beneficial, the current clinical data indicate that apremilast is an effective and well tolerated option for the management of psoriasis and PsA in adults.

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.

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.