Ascomycins: promising agents for the treatment of inflammatory skin diseases

The Efficacy and Safety of Pimecrolimus in Patients With Facial Seborrheic Dermatitis: A Systematic Review of Randomized Controlled Trials

Facial seborrheic dermatitis (SD) is a chronic inflammatory skin condition that can affect the quality of life with frequent recurrences. There is no medication as yet to cure this disease completely. There are four general categories of agents that are used to treat SD: antifungal agents, keratolytics, corticosteroids, and lastly calcineurin inhibitors. Topical therapies are the mainstream line of treatment to be used for this skin condition.

The objective of this article is to critically review the published data in the literature on the use of topical pimecrolimus 1% topical cream as an option for treating facial SD. The final purpose of this review is to answer two questions: whether pimecrolimus topical cream is effective for the treatment of SD compared to the conventional current treatments and how safe is this treatment. 

The PubMed, Clinicaltrials.gov, MEDLINE + Embase, and Cochrane library databases were searched for original randomized clinical trials (RCTs) evaluating pimecrolimus 1% topical cream and comparing it with other topical treatments for SD. A systematic review and meta-analysis were then conducted on the selected studies by grading the evidence and qualitative comparison of results among and within studies. A total of five studies were included in the review; however, only four were eligible for inclusion in the meta-analysis, in which pimecrolimus was compared with other treatments for the management of facial SD.

Pimecrolimus was found to be an effective topical treatment for facial SD, as it showed considerable desirable control of the symptoms in patients with facial SD clinically, in addition to a lower recurrence or relapsing rates; however, it had more side effects compared to other topical treatments, but the side effects were mild and tolerable.

Trilayer microneedle array assisted transdermal and intradermal delivery of dexamethasone

Dexamethasone is a synthesised glucocorticoid that is widely used in the treatment of various inflammatory skin conditions. Novel trilayer dissolving microneedle arrays were manufactured to assist dexamethasone delivery via the skin. Both transdermal delivery and intradermal delivery of dexamethasone can be achieved this way. Additionally, we proposed a novel strategy of co-formulating dexamethasone and its pro-drug dexamethasone sodium phosphate into the same dissolving microneedle array, with a view to achieving a fast onset of action and also sustained treatment. Here, a 3D-printing technique was employed, for the first time, to fabricate a baseplate for these microneedle arrays. The 3D-printed baseplates provided strong support to aid the insertion of the drug-encapsulated tips. A simple and rapid HPLC method was developed, and validated, to separate and quantify dexamethasone and dexamethasone sodium phosphate in the same sample. Ex-vivo studies found that these trilayer dissolving microneedle arrays could achieve a delivery efficiency of over 40% in intradermal delivery and over 50% in transdermal delivery. Trilayer microneedle-assisted delivery of this glucocorticoid provided a promising alternative to oral and parenteral routes of dexamethasone administration.

Pharmacological management of atopic dermatitis in the elderly

INTRODUCTION

The prevalence of atopic dermatitis (AD) in geriatric populations of industrialized countries is currently estimated at 3-4% and continues to increase. AD is associated with significant morbidity, increased susceptibility to infection, and symptoms of pruritus and pain. Treatments may negatively affect elderly patients; thus, plans should be optimized for this population.

AREAS COVERED

This review summarizes treatment options for AD in the elderly. A systematic review of the literature was conducted using the key terms atopic dermatitis, elderly, geriatric, systemic therapy, therapy, and topical therapy in PubMed. Searches yielded articles on skincare management and topical and systemic pharmacotherapies.

EXPERT OPINION

Proper use of moisturizer is crucial in all patients with AD. Topical corticosteroids are commonly prescribed; however, they carry an increased risk of adverse events such as skin atrophy. Systemic corticosteroids should be avoided in elderly patients due to questionable efficacy and increased adverse events. Topical calcineurin inhibitors and crisaborole are similarly efficacious with an excellent safety profile. Cyclosporine, azathioprine, methotrexate, and mycophenolate mofetil are systemic agents available for the treatment of refractory AD; however, insufficient data exist to indicate the superiority of any one agent. Dupilumab is a safe and efficacious injectable therapy in elderly patients.

Importance of microbial natural products and the need to revitalize their discovery

Microbes are the leading producers of useful natural products. Natural products from microbes and plants make excellent drugs. Significant portions of the microbial genomes are devoted to production of these useful secondary metabolites. A single microbe can make a number of secondary metabolites, as high as 50 compounds. The most useful products include antibiotics, anticancer agents, immunosuppressants, but products for many other applications, e.g., antivirals, anthelmintics, enzyme inhibitors, nutraceuticals, polymers, surfactants, bioherbicides, and vaccines have been commercialized. Unfortunately, due to the decrease in natural product discovery efforts, drug discovery has decreased in the past 20 years. The reasons include excessive costs for clinical trials, too short a window before the products become generics, difficulty in discovery of antibiotics against resistant organisms, and short treatment times by patients for products such as antibiotics. Despite these difficulties, technology to discover new drugs has advanced, e.g., combinatorial chemistry of natural product scaffolds, discoveries in biodiversity, genome mining, and systems biology. Of great help would be government extension of the time before products become generic.

Topical pimecrolimus: A new horizon for vitiligo treatment?

OBJECTIVES

The purpose of this study was to assess the efficacy of pimecrolimus cream 1% in vitiligo and to evaluate the effects of age of the patients, age of onset and duration of disease on response rate.

MATERIALS AND METHODS

Twenty-three patients with vitiligo were enrolled in our study; 19 patients (seven male, 12 female) completed the 6-month study period. Patients were treated with topical pimecrolimus 1% cream once daily. The response was evaluated as excellent (76-100%), moderate (51-75%), mild (26-50%), minimal (1-25%), or no response.

RESULTS

The mean age of the 19 patients was 29.3+/-16.6 (range 7-62 years) and the mean duration of vitiligo was 68.4+/-81.3 months. Three patients demonstrated an excellent response to the therapy. Four patients had moderate, six patients had mild and five patients had minimal responses; one patient had no response to the treatment. Side effects were noted as a burning and stinging sensation in only three patients. The correlations between response rate and duration of the disease (r = 0.02, p = 0.95), onset age (r = -0.17, p = 0.48), and age of the patients (r = -0.16, p = 0.53) were not significant.

CONCLUSIONS

Pimecrolimus has a mild therapeutic effect on vitiligo without significant side effects and can be an alternative therapy agent.

Role of topical calcineurin inhibitors in the treatment of seborrheic dermatitis: a review of pathophysiology, safety, and efficacy

Seborrheic dermatitis (SD) is characterized by erythematous pruritic patches and plaques with greasy scale that occur in sebaceous areas. It is common, affecting up to 3% of the population. Past treatments have relied on a wide variety of anti-inflammatory and antifungal agents, but corticosteroids have limited use because of long-term adverse effects. Topical calcineurin inhibitors provide a safe alternative for the treatment of SD, as these drugs block the inflammatory cascade involved in the disease process and pose no risk of skin atrophy. Studies of topical pimecrolimus and tacrolimus in the treatment of SD have found that improvement occurred within 2 weeks, and if SD recurred after stopping treatment, it was significantly less severe. There have been no studies of the comparative efficacy of pimecrolimus versus tacrolimus for the treatment of SD. Common adverse effects of mild burning and irritation have been associated with the use of both of these agents. Safety profile studies are limited to studies of atopic dermatitis, which show no increase in infection rate, photocarcinogenicity, or signs of immunosuppression in patients using topical calcineurin inhibitors for long-term treatment. This article reviews the clinical trials of pimecrolimus and tacrolimus in the treatment of SD, focusing on efficacy and safety.

Treatment with pimecrolimus cream 1% clears irritant dermatitis of the periocular region, face and neck

BACKGROUND

Irritant dermatitis of the face and neck is particularly prevalent in women > or = 30 years old, who typically present with periocular cutaneous symptoms. Current therapies are limited, indicating a need for rapid, effective alternatives. Pimecrolimus cream 1%, a nonsteroid, cell-selective inhibitor of inflammatory-cytokine release, is effective in the treatment of inflammatory skin diseases, such as chronic irritant dermatitis of the hands, and thus offers a potential therapeutic option for this indication. This study reports on the safety and efficacy of pimecrolimus treatment in patients with irritant periocular dermatitis, extending to the face and neck in some patients.

METHODS

Twenty-seven patients with periocular irritant dermatitis (extending onto the face and neck in eight) were treated twice daily with pimecrolimus cream 1% for 7 d, followed by once-daily application for a further 7 d. Erythema, swelling, and pruritus were assessed at baseline, weeks 1-4 using a 4-point clinical score (0, absent; 1, mild; 2, moderate; and 3, severe).

RESULTS

All patients showed marked improvement within 2-3 d of treatment with disease clearance in 23 of 27 patients within 14 d. In the remaining four patients, mild relapse occurred at weeks 3-4, but improvement was observed following a further 10-d treatment. Side-effects were mild and transient.

CONCLUSION

Pimecrolimus cream 1% provides a new potential option for treatment of irritant dermatitis of the periocular region, head and neck. Further double-blind, controlled studies are required to confirm the efficacy and safety of pimecrolimus cream 1% for this indication.

Calcineurin inhibitors for the treatment of atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a chronic disease characterized by periods of remission and relapse. Therapeutic objectives for AD should be to quickly reduce disease symptoms by targeting pathophysiological pathways, and to provide long-term management by reducing recurrences.

OBJECTIVE

Calcineurin inhibitors currently appear to be one of the most promising alternative systemic and topical compounds to treat AD. This review focuses on new developments of topical calcineurin inhibitors, therapeutic regimens including long-term management, and prophylaxis of AD.

METHODS

The published clinical studies that present data on treatment of AD with calcineurin inhibitors were assessed.

RESULTS/CONCLUSION

Topical calcineurin inhibitors such as tacrolimus and pimecrolimus provide an effective treatment for AD. They are useful for long-term management and prophylaxis of AD. Safety concerns with regard to increased risk for lymphomas or skin cancer could not be confirmed but will remain under careful observation.

Steroid-sparing effect of pimecrolimus cream 1% in children with severe atopic dermatitis

OBJECTIVE

To investigate if pimecrolimus cream 1% reduces the need for steroids in the long-term management of severe pediatric atopic dermatitis (AD).

METHODS

A total of 184 pediatric patients (aged 2-17 years) with a history of severe AD according to Rajka and Langeland were enrolled. Patients were randomized to treatment with pimecrolimus cream or vehicle cream for a 24-week period. Prednicarbate 0.25% was applied as rescue medication.

RESULTS

Patients on pimecrolimus required steroids on a mean of 29% of study days, compared with 35% of patients on vehicle (p = 0.1841). On the head and neck only, the respective figures were 10 versus 19% (p = 0.0009). In patients enrolled with acute severe disease (Investigator's Global Assessment > or = 4), steroids were used on 28% of the days in the pimecrolimus group compared to 45% in the control group (p = 0.0024). On the head and neck, steroids were used on 10% of study days with pimecrolimus versus 30% with vehicle (p < 0.0001).

CONCLUSION

The results indicate that the need for topical steroids on the head and neck is reduced with pimecrolimus cream 1% in the management of severe pediatric AD according to the definition of Rajka and Langeland.

Blood concentrations of pimecrolimus in adult patients with atopic dermatitis following intermittent administration of pimecrolimus cream 1% (Elidel) for up to 1 year

OBJECTIVES

To determine blood concentrations of pimecrolimus after long-term intermittent administration of pimecrolimus cream 1% in adult patients with extensive atopic dermatitis (AD).

METHODS

This was an open-label, multiple topical dose study in adults with moderate to severe AD and a total body surface area (TBSA) involvement of at least 20%. Pimecrolimus cream 1% was administered twice daily according to treatment need for up to 12 months to all lesions, including the neck and face. Blood samples were collected at regular time points and pimecrolimus concentrations were measured using a radioimmunoassay with a limit of quantitation (LoQ) of 0.5 ng/ml.

RESULTS

Forty patients (19 females), aged from 19 to 59 years, with moderate to severe AD entered the study. Twenty patients completed 6 months and 13 completed 1 year in the study. The individual blood concentrations of pimecrolimus were consistently low and there was no sign of drug accumulation. In 900 of the 918 samples examined (98%), pimecrolimus concentrations remained below the LoQ. The maximum concentration observed throughout the entire study was 0.8 ng/ml.

CONCLUSION

Long-term intermittent treatment of adult patients with extensive AD with pimecrolimus cream 1% is associated with minimal systemic exposure and no evidence of drug accumulation.

Penetration of ASM 981 in canine skin: a comparative study

ASM 981 has been developed for topical treatment of inflammatory skin diseases. It specifically inhibits the production and release of pro-inflammatory cytokines. We measured the skin penetration of ASM 981 in canine skin and compared penetration in living and frozen skin. To make penetration of ASM 981 visible in dog skin, tritium labelled ASM 981 was applied to a living dog and to defrosted skin of the same dog. Using qualitative autoradiography the radioactive molecules were detected in the lumen of the hair follicles until the infundibulum, around the superficial parts of the hair follicles and into a depth of the dermis of 200 to 500 microm. Activity could not be found in deeper parts of the hair follicles, the dermis or in the sebaceous glands. Penetration of ASM 981 is low in canine skin and is only equally spread in the upper third of the dermis 24 hours after application. Penetration in frozen skin takes even longer than in living canine skin but shows the same distribution.

Low systemic absorption and good tolerability of pimecrolimus, administered as 1% cream (Elidel) in infants with atopic dermatitis--a multicenter, 3-week, open-label study

Pimecrolimus cream 1%, a nonsteroid inhibitor of inflammatory cytokines, offers an alternative to corticosteroids in the treatment of atopic dermatitis. Here we evaluate pimecrolimus blood concentrations and tolerability to pimecrolimus cream 1% in 22 infants below 2 years of age with atopic dermatitis (10-92% body surface area affected at baseline). Efficacy was assessed as a secondary objective. Pimecrolimus cream 1% was applied twice daily for 3 weeks. Blood concentrations were low, typically (96% of total 100 concentrations measured) below 2 ng/mL, the majority (71%) remaining below 0.5 ng/mL. The highest concentration observed was 2.26 ng/mL. At steady state, there was no indication of accumulation. Pimecrolimus was well tolerated locally and systemically, with no serious adverse events recorded. Most adverse events recorded (35 in 17/22 patients) were typical of the young pediatric population studied, of mild to moderate severity, and not considered to be study-medication related, with the exception of four local adverse effects limited to the site of cream application. No clinically relevant change was observed in physical examination, vital signs, or laboratory safety parameters. A rapid onset of therapeutic effect was observed within the first four days of treatment. Pimecrolimus cream 1% is well tolerated in infants 3 to 23 months of age treated for 3 weeks, and results in minimal systemic exposure.

Safety and efficacy of topical calcineurin inhibitors in the treatment of childhood atopic dermatitis

Approximately 10-20% of infants in industrialized countries experience atopic dermatitis. In recent decades topical corticosteroids have been the first-choice therapy for treatment of flares. However, this form of therapy may induce skin atrophy, especially after application to facial lesions or with long-term use. Thus, development of new anti-inflammatory topical agents for the treatment of childhood atopic dermatitis was needed. The topical calcineurin inhibitors tacrolimus and pimecrolimus have an effect on various cells of the cutaneous immune system, specifically on T cells, by inhibiting the phosphatase calcineurin and preventing the transcription of proinflammatory cytokines. In several clinical studies of children and adults with atopic dermatitis, topical calcineurin inhibitors were found to be effective both on the face and the trunk and extremities, in both short- and long-term treatment regimens. Tachyphylaxis or rebound were not observed. In most patients an improvement of their eczema occurred during the first week of treatment, as measured by subjective and objective clinical signs of atopic dermatitis. Treatment significantly reduced the incidence of flares and the need for corticosteroids in children and adults. Treatment success, commonly defined as 'excellent improvement' or 'clearing of all lesions', was observed in more than one-third of all children treated with 0.03% or 0.1% tacrolimus or 1% pimecrolimus. Topical application of pimecrolimus and tacrolimus does not lead to significant blood concentrations of these agents in the majority of children with atopic dermatitis, and any increase in blood concentrations decreases after a few days of therapy. No changes in laboratory parameters were observed in short- and long-term studies in patients with atopic dermatitis. The most common adverse effect following the application of topical calcineurin inhibitors is mild to moderate symptoms of irritation such as burning, erythema and pruritus, which occurred in up to 20% of all children treated with tacrolimus and 10% of children treated with pimecrolimus, and usually faded after a few days. In contrast to topical corticosteroids, calcineurin inhibitors do not induce skin atrophy, even after long-term use. Topical calcineurin inhibitors have been proven to be effective and have a good safety profile during short-term and long-term use for up to 1 year with pimecrolimus and up to 4 years with tacrolimus. Given the lack of extensive experience with use of topical calcineurin inhibitors over longer periods, regular use of these agents, particularly in children, should be undertaken only after careful consideration of individual cases. Sun protection should also be advised.

Inflammatory cell numbers and cytokine expression in atopic dermatitis after topical pimecrolimus treatment

BACKGROUND

In several clinical trials the topical application of pimecrolimus was shown to be effective in the treatment of atopic dermatitis (AD). By targeting calcineurin-dependent signaling pathways, pimecrolimus controls cytokine gene expression. The purpose of this study was to investigate the effect of pimecrolimus on the inflammatory infiltrate and cytokine expression pattern in AD upon topical therapy.

METHODS

From 10 patients with acute AD, skin biopsies as well as immunophenotype and cytokine production of peripheral blood mononuclear cells (PBMC) were examined before and 3 weeks after therapy.

RESULTS

The clinical improvement was associated with a marked regression of histopathological features. In particular, the density of the inflammatory infiltrate mostly containing lymphocytes and eosinophils declined. By double immunofluorescent staining, a reduced expression of the T helper (Th) 2 cytokines interleukin (IL)-5, IL-10, and IL-13 in both CD4+ and CD8+ T cells was demonstrated after therapy. Pimecrolimus therapy was also associated with a reduced expression of the Th1 cytokine interferon (IFN)-gamma. Interestingly, the numbers of epidermal CD1a+ dendritic cells increased following treatment. In the peripheral blood, a decrease of lymphocytes and eosinophils was noticed, but the distribution of lymphocyte subpopulations and their capacity of cytokine production did not change.

CONCLUSIONS

Topical pimecrolimus exhibits anti-inflammatory effects in AD by reducing the inflammatory cell infiltrate and cytokine expression in the dermis.

[New treatments of atopic dermatitis]

Topical steroids are still used suboptimally, but remain the mainstay of atopic dermatitis treatment. Topical steroid phobia is rampant in many countries, a real advantage for the entry on the market of topical immunomodulators (TIMs), which inhibit both antigen specific and non-specific T cell activation in the skin, by blockade of gene transcription of proinflammatory cytokines such as IL2 and TNF alpha. Topical tacrolimus and pimecrolimus have the most advanced clinical development. Tacrolimus, already used orally in transplantation medicine, is already available in France since 2003 as a 0.03% ointment for children (Protopic, Fujisawa). Its introduction on the market has substantially changed prescription habits in atopic dermatitis. Recalcitrant adolescent and adult head and neck lesions are the major target, but the drug is is also widely used in children, with a good safety profile. The risk of herpes virus superinfections did not increase significantly in clinical trials but needs further monitoring. Long-term prescription will need a closer look at a still much debated increased skin cancer risk. The marked efficacy on thin skin sites and absence of atrophogenic properties of the drug balance its side effects at the first applications on inflamed skin (pruritus, burning sensation). Clinical studies using pimecrolimus (Elidel, Novartis), marketed as a 1% cream, show a satisfactorily efficacy profile in adults and children including infants. The drug is better tolerated and is already widely introduced on the international market since 2002 with a pediatric positioning, but is nor available yet in 2004 in France. Besides phototherapy, systemic immunosuppressants remain useful drugs in severe disease especially in older children and adolescents, cyclosporin remaining the leading drug. Preventive immunomodulation modifying the intestinal microflora is very promising approach which deserves a large-scale assessment.

Pimecrolimus for the treatment of inflammatory skin disease

Pimecrolimus (SDZ ASM 981, Elidel ) is an ascomycin macrolactam derivative and a cell-selective inhibitor of inflammatory cytokines specifically developed to treat inflammatory skin diseases. Pimecrolimus combines high anti-inflammatory activity in the skin with a low potential to impair systemic immune reactions. Multi-centre studies have proved the efficacy and safety of pimecrolimus cream in patients with atopic dermatitis (AD) and confirmed that it is suitable for short-term treatment and long-term management of AD in adults, children and infants as young as 3 months. Topical application in humans is not associated with the atrophogenic side effects observed with corticosteroids. Pimecrolimus blood levels remained consistently low after repeated topical application and no clinically relevant drug-related systemic adverse events have been reported among the 8000 patients treated in clinical trials so far. Short-term, Phase I/II and Phase II trials of pimecrolimus administered orally in psoriasis and AD have shown that this drug is highly effective in a dose-dependent manner in patients with these diseases and has high safety profile. This finding is confirmed by pharmacogenomic blood analysis. Available data thus indicates that pimecrolimus, in both the cream and oral formulations, may represent a new option for the treatment of inflammatory skin diseases.

New Treatment Modalities for Vitiligo

The development of effective treatment modalities for vitiligo is dependent on an understanding of the events leading to depigmentation. However, the exact pathogenesis of vitiligo is still mostly unknown. Abnormalities in both humoral and cell-mediated immunity have been documented in vitiligo patients and they present a basis for using immunomodulating agents, such as corticosteroids and macrolide immunomodulators, in the treatment of vitiligo. Macrolide immunomodulators, such as tacrolimus and pimecrolimus, which can be used topically, are known as topical immunomodulators (TIMs). TIMs inhibit the action of calcineurin, and consequently inhibit T-cell activation and the production of various cytokines; this is considered the working mechanism of action of TIMs in vitiligo. Several small studies and case reports on the use of TIMs in vitiligo have been published so far. Tacrolimus achieves better results on the face and neck than on other body areas. Particular advantages of TIMs are safety in treating these areas because of lack of skin atrophy and good tolerability. The incidence of application site adverse events in vitiligo seems to be lower than in the treatment of atopic dermatitis. On the face and neck, TIMs may become a useful tool in the treatment of adults and children with vitiligo despite possibly lower efficacy than topical corticosteroids. Further, larger, controlled clinical studies are warranted to determine the definite role of TIMs as monotherapy or in combination with other modalities in the treatment of vitiligo.

Current concepts and review of pimecrolimus in the treatment of psoriasis

The ascomycine macrolactam derivative pimecrolimus has a gene profile of broad anti-inflammatory activity without evidence of toxicity. It exhibits excellent clinical tolerability after 4 weeks and 12 weeks, respectively, of oral treatment, and it is highly effective in a concentration-dependent manner in patients with moderate to severe plaque psoriasis. Although not yet approved, oral pimecrolimus promises to be a novel, highly effective, and well-tolerated drug in the systemic treatment of psoriasis and other T-cell-mediated skin diseases.

Anti-inflammatory effect of topical nanocrystalline silver cream on allergic contact dermatitis in a guinea pig model

The anti-inflammatory activity of topical nanocrystalline silver cream was assessed and compared with the effects of topical steroids and currently available immunosuppressants using a guinea pig model of allergic contact dermatitis. Dermatitis was induced with dinitrochlorobenzene and treated with different concentrations of nanocrystalline silver, medium and high potency steroids, tacrolimus and pimecrolimus, or appropriate vehicles once daily for 5 days. Erythema was evaluated daily (on a score of 0 to 4, from absent to very severe) and histopathology of the skin biopsies was evaluated after 5 days of treatment. Prior to treatment, the average scores of erythema in all the groups were in the range of 3(+) to 4(+). In the no treatment and vehicles groups these scores remained at about this level for the subsequent 5 days of the study. Nanocrystalline silver reduced erythema within 1 day of treatment in a concentration-dependent manner with significant reduction at silver concentrations of 0.5% and 1% (P < 0.05) and this reduction progressed throughout the study period. Steroids and immunosuppressants produced similar decreases in erythema, with no significant differences compared to 0.5% and 1% nanocrystalline silver. In skin biopsies scored for degree of inflammatory response, effects of treatments mirrored erythema results. This study suggests that nanocrystalline silver cream may have therapeutic potential for topical treatment of inflammatory skin diseases.

Systemic exposure, tolerability, and efficacy of pimecrolimus cream 1% in atopic dermatitis patients

AIMS

To measure pimecrolimus blood concentrations and to evaluate tolerability and efficacy in children and infants treated topically for atopic dermatitis with pimecrolimus cream 1% for three weeks.

METHODS

Three open label, non-controlled, multiple topical dose studies were conducted in children aged 8-14 years (study A, ten patients), and in infants aged 8-30 months (study B, eight patients) and 4-11 months (study C, eight patients). Pimecrolimus blood concentrations were determined on days 4 and 22 of treatment, and at end of study. Efficacy was assessed using the Eczema Area and Severity Index (EASI).

RESULTS

Pimecrolimus blood concentrations were consistently low, typically (81%) below 1 ng/ml, with more than half of the measurements below the assay limit of quantitation (0.5 ng/ml) in studies A and B. The highest blood concentration measured throughout the three studies was 2.6 ng/ml. The cream was well tolerated, locally and systemically. The most common adverse event suspected to be related to study medication was a transient mild to moderate stinging sensation at the application site in 5/26 patients. There was no indication of any systemic adverse effect. The patients responded well to therapy with a rapid onset of action, usually within four days. Median reductions of EASI from baseline at day 22 were 55% (study A), 63% (study B), and 83% (study C).

CONCLUSION

Three weeks treatment of children and infants with extensive atopic dermatitis, using pimecrolimus cream 1% twice daily, is well tolerated and results in minimal systemic exposure, at which no systemic effect is expected.

Pimecrolimus: a review

Pimecrolimus (SDZ ASM 981), an ascomycin derivative, is one of the new classes of immunomodulating macrolactams and was specifically developed for the treatment of inflammatory skin diseases. The interest in pimecrolimus has been substantial because of its significant anti-inflammatory activity and immunomodulatory capabilities and its low systemic immunosuppressive potential. The mechanism of action of pimecrolimus is the blockage of T cell activation. Pimecrolimus (like all ascomycins) is an immunophilin ligand, which binds specifically to the cytosolic receptor, immunophilin macrophilin-12. This pimecrolimus-macrophilin complex effectively inhibits the protein phosphatase calcineurin, by preventing calcineurin from dephosphorylating the nuclear factor of activated T cells (NF-AT), a transcription factor. This results in the blockage of signal transduction pathways in T cells and the inhibition of the synthesis of inflammatory cytokines, specifically Th1- and Th2-type cytokines. Pimecrolimus has also been shown to prevent the release of cytokines and pro-inflammatory mediators from mast cells. Several studies have evaluated the effectiveness of pimecrolimus as a treatment for skin diseases. In animal models of allergic contact dermatitis, topical pimecrolimus was found to be effective. In human studies of allergic contact dermatitis pimecrolimus demonstrated significantly more efficacy than the control treatment. As well, the effectiveness of pimecrolimus 0.6% cream was comparable to 0.1% betamethasone-17-valerate; however, pimecrolimus was not associated with any of the side effects characteristic of a topical steroid. Topical application of pimecrolimus is not associated with skin atrophy. Pimecrolimus is effective and safe in both children and adults with atopic dermatitis. When pimecrolimus 1% cream has been applied to adult atopics, improvement has been observed as early as the first week, with a 72% reduction in severity after 3 weeks. Pharmacokinetic studies have shown very low blood levels of pimecrolimus following topical application, with no accumulation after repeated applications. Following application of pimecrolimus cream occasional transient irritation may be experienced at the application site. Similar results have also been found in children aged 3 months and older following application of pimecrolimus 1% cream. Topical pimecrolimus in psoriasis appears to exhibit a dose-dependent therapeutic effect under semi-occlusive conditions. Pimecrolimus has an enormous potential as a new treatment of inflammatory skin diseases. It has been shown to be effective in atopic and allergic contact dermatitis, with a favorable adverse-effects profile, which includes little effect on the systemic immune response.

Alopecia areata: treatment of today and tomorrow

It is the aim of this article to review and appraise available data on treatments for alopecia areata (AA) according to the demands of evidence based medicine. Studies evaluating the efficacy of a treatment for AA should include appropriate controls, use cosmetically acceptable hair regrowth as a parameter for treatment success, include patients with AA totalis, universalis or extensive patchy AA, and exclude patients suffering from AA for less than 3 months. Moreover, the treatment must be safe over a prolonged period of time. Among the various therapeutic approaches presently available for AA, only treatment with contact sensitizers such as diphenylcyclopropenone or squaric acid dibutylester has been shown to be effective in studies that fulfill these criteria. Improved future treatments may be immunosuppressive or immunomodulatory targeting of the autoimmune pathogenesis of AA, or they may otherwise protect hair follicles from the injurious effects of inflammation. Such possible future therapeutic approaches include the incorporation of immunomodulatory agents into liposomes as an improved vehicle; inhibition of apoptosis mediated by the Fas-FasL system; inhibition of the lymphocyte homing receptor CD44v10; induction of tolerance.

Pharmacokinetics of Pimecrolimus, a Novel Nonsteroid Anti-Inflammatory Drug, After Single and Multiple Oral Administration

OBJECTIVE

To investigate the pharmacokinetics and tolerability of the new nonsteroid anti-inflammatory pimecrolimus (SDZ ASM 981, Elidel) after oral administration.

DESIGN

A single-dose, randomised, double-blind, placebo-controlled, dose-rising, parallel-group study in healthy male volunteers, and a multiple-dose, randomised, double-blind, placebo-controlled, dose-rising study in patients with psoriasis.

SETTING

One centre in France (single-dose study) and one centre in Austria (multiple-dose study).

METHODS

The first study investigated the pharmacokinetics and tolerability of ascending single oral doses of pimecrolimus (5-60mg). The 60mg dose was repeated in the same subjects after a fat-rich breakfast. The second study investigated the pharmacokinetics, tolerability, safety and efficacy of rising oral doses administered once daily (5-20mg) or twice daily (20 and 30mg) for 28 days. Only the pharmacokinetic, safety and tolerability data of this study are presented.

OUTCOME MEASURES AND RESULTS

Oral administration of pimecrolimus was well tolerated up to the highest dose (60mg). Pimecrolimus was rapidly absorbed (time to maximum blood concentration 0.7-2 hours). A high-fat meal before drug administration delayed the time to peak concentration. Blood concentrations appear to have a long-terminal half-life (30-40 hours after a single dose in fasted subjects, 50-100 hours after the final dose on day 28 in psoriasis patients). After multiple doses, steady state was attained after 6-13 days. Maximum blood concentrations (C(max)) and exposure (area under the concentration-time curve; AUC) were broadly dose proportional. At the highest dose administered in the multiple-dose study (30mg twice daily), a C(max ) of 54.7 microg/L was measured and an AUC(24) of 589.8 microg.h/L was calculated at steady state (day 13).

CONCLUSION

The results support further evaluation of the therapeutic potential of oral pimecrolimus for the treatment of inflammatory diseases.

Pimecrolimus inhibits up-regulation of OX40 and synthesis of inflammatory cytokines upon secondary T cell activation by allogeneic dendritic cells

Pimecrolimus is a new non-steroidal inhibitor of T cell and mast cell activation. In the present study, we compared the potency of pimecrolimus and cyclosporin A (CyA) to inhibit cytokine synthesis of alloantigen-primed T cells and the expression of CD134 (OX40), an inducible co-receptor molecule thought to be critical for the survival and expansion of inflammation-mediating T cells. To mimic the physiological situation of recurrent antigenic stimulation, we have used dendritic cells (DC) as stimulators of purified CD4+ T cells in the primary and secondary allogeneic mixed lymphocyte culture (allo-MLC). Pimecrolimus inhibited surface expression of OX40 and prevented the up-regulation of CD25 and CD54 with a 10-fold higher potency compared to CyA. Similarly, 50% inhibition of allo-DC-mediated T cell proliferation by pimecrolimus was obtained at 0.55 nm, compared to about 12 nm for CyA. Furthermore, pimecrolimus blocked the increase of OX40 on primed T cells restimulated on day 10 in secondary allo-MLC. Allo-DC-primed T cells showed a restricted cytokine profile characterized by the production of TNF-alpha, IFN-gamma and IL-2 but low to undetectable levels of IL-4 and IL-10. The synthesis of TNF-alpha and IFN-gamma and the up-regulation of OX40 on T cells after secondary allogeneic stimulation were almost entirely blocked by 10 nm pimecrolimus. Taken together, pimecrolimus inhibits T cell proliferation and Th1 cytokine synthesis and also prevents the up-regulation of the OX40 co-receptor on primed T cells indicating its potential in the therapy of chronic inflammation and autoimmunity.

Pimecrolimus identifies a common genomic anti-inflammatory profile, is clinically highly effective in psoriasis and is well tolerated

The ascomycin macrolactam pimecrolimus is a novel inflammatory cytokine release inhibitor that so far has not been administered systemically to humans. In this phase I/II randomized double-blind, placebo-controlled, multiple rising dose proof of concept study psoriasis patients were treated with oral pimecrolimus or placebo. Gene profiling identified a common genomic profile with a downregulation of genes associated with inflammation but no changes in gene expression linked to drug-related side-effects. A steady state of pimecrolimus was reached after 5-10 d, Cmax, and area under the curve (0-24) was 54.5 ng per ml and 589.9 ng h per ml, respectively, at steady state at the highest dose. There was clear clinical efficacy in patients receiving 20 mg pimecrolimus twice daily and 30 mg twice daily with a reduction of Psoriasis Area and Severity Index by 60% and 75%, respectively. Histopatho logically and immunopathologically there was a reversion of the psoriatic phenotype towards normal. There were no notable clinical, laboratory, kidney function, or immunologic side-effects. We conclude that pimecrolimus taken orally is highly effective in a concentration-dependent manner in patients with psoriasis and on a short-term basis it is well tolerated and this is confirmed by its pharmacogenomic profile. The latter also indicates that pimecrolimus should be equally effective in other inflammatory skin diseases.

Topical pimecrolimus: a review of its clinical potential in the management of atopic dermatitis

Pimecrolimus (SDZ ASM 981), an ascomycin derivative, is a nonsteroid, has anti-inflammatory activity, and has demonstrated efficacy in reducing symptoms of atopic dermatitis in adult and paediatric patients when applied topically. Compared with vehicle, topical pimecrolimus 1.0% cream was significantly more effective at reducing symptoms of atopic dermatitis, as measured by the Eczema Area and Severity Index (EASI), in infants aged 3 to 23 months, children aged 2 to 17 years and adults. The median reductions from baseline in the total EASI score in adults after treatment with pimecrolimus 1.0% or corresponding vehicle twice daily for 3 weeks were 47 and 0%, respectively. In infants and children, treatment with pimecrolimus 1.0% twice daily for 6 weeks resulted in significant decreases in mean EASI scores compared with vehicle. The severity of pruritus was significantly reduced in patients of all age groups after topical treatment with pimecrolimus 1.0% cream. Compared with vehicle, the incidence of eczematous flares was also reduced by intermittent long-term use of topical pimecrolimus 1.0% in adults, children and infants. Sixty percent of children treated with pimecrolimus for 1 year completed the first 6 months of treatment without experiencing a flare, compared with 35% of patients who received vehicle. Furthermore, the use of topical corticosteroids for the treatment of uncontrolled flares in adults, children and infants was lower in the pimecrolimus groups than in the vehicle groups. Topical pimecrolimus 1.0% cream is well tolerated in atopic dermatitis patients of all age groups. There were no clinically relevant systemic adverse events reported from any of the studies in patients with atopic dermatitis. The most frequently reported adverse events pertained to application site reactions, such as burning and a feeling of warmth. In conclusion, topical pimecrolimus 1.0% cream has shown efficacy in the treatment of mild to moderate atopic dermatitis in infants, children and adults. Although tolerability data concerning infants and children have not yet been published in full, the drug appears to be well tolerated in all age groups, and there have been no reports of clinically relevant systemic adverse events. Furthermore, pimecrolimus 1.0% cream has shown no potential for skin atrophy, a problem commonly associated with treatment with topical corticosteroids. Pimecrolimus 1.0% cream provides a promising and well tolerated treatment option in the management of infants, children and adults with mild to moderate atopic dermatitis.

Pimecrolimus (Elidel, SDZ ASM 981)--preclinical pharmacologic profile and skin selectivity

The ascomycin macrolactam derivative pimecrolimus (Elidel, SDZ ASM 981; Novartis Pharma AG, Basel Switzerland) is a cell-selective inhibitor of inflammatory cytokines specifically developed for the treatment of inflammatory skin diseases, such as atopic dermatitis, allergic contact dermatitis, irritant contact dermatitis, and plaque-type psoriasis. It inhibits the production of inflammatory cytokines in T cells and mast cells and prevents the release of preformed inflammatory mediators from mast cells. Topically administered pimecrolimus is as effective as the high-potency corticosteroid clobetasol-17-propionate in a pig model of allergic contact dermatitis (ACD). Unlike clobetasol, however, it does not cause skin atrophy. Given orally, pimecrolimus is as potent or superior to tacrolimus (FK 506) in treating ACD in mice and rats. Pimecrolimus also effectively reduces skin inflammation and pruritus in hypomagnesemic hairless rats, a model that mimics acute signs of atopic dermatitis. Pimecrolimus shows only a low potential to impair systemic immune responses when compared with tacrolimus as shown in rats in (1) the localized graft-versus-host reaction, (2) the antibody formation to sheep red blood cells, and (3) kidney transplantation. Pimecrolimus permeates through pig skin in vitro at a 10-times lower rate than tacrolimus, indicating a lower potential for percutaneous absorption in vivo. The data suggest that pimecrolimus combines high anti-inflammatory activity in the skin with a low potential to impair systemic immune reactions.

Pimecrolimus cream 1%: a new development in nonsteroid topical treatment of inflammatory skin diseases

Atopic dermatitis (AD) is one of a family of inflammatory skin diseases (psoriasis, irritant contact dermatitis, and allergic contact dermatitis). Dermal inflammation and production of proinflammatory cytokines by activated T cells is a prominent and defining characteristic in all of these conditions. Corticosteroids, though effective and potent immunosuppressants, are associated with a number of systemic and local adverse effects. The ascomycin derivative pimecrolimus (formerly ASM 981) is a nonsteroid with topical anti-inflammatory activity. Pimecrolimus cream 1% is minimally absorbed into the circulation; thus, it has a low bioavailability-reducing the risk for systemic adverse effects. The efficacy and safety of pimecrolimus cream 1% has been well shown in diverse patient populations with inflammatory skin diseases in several well-controlled trials. Significant and rapid amelioration of the signs and symptoms of AD was established in 3 studies lasting 6 weeks each, evaluating 589 pediatric patients. In a 1-year study, pimecrolimus was applied at the first signs and symptoms of eczema to prevent the progression of AD to flares. Flares were prevented in over 50% of patients who used pimecrolimus cream 1%, reducing or completely eliminating the need for topical corticosteroids during a 1-year treatment period. Results in pimecrolimus studies in chronic irritant hand dermatitis and chronic hand dermatitis of mixed causes indicate potential for use in these important diseases, and further study in these indications is warranted.

The ascomycin macrolactam pimecrolimus (Elidel, SDZ ASM 981) is a potent inhibitor of mediator release from human dermal mast cells and peripheral blood basophils

BACKGROUND

The ascomycin macrolactam pimecrolimus (Elidel, SDZ ASM 981) has recently been developed as a novel and cell-selective inhibitor of inflammatory cytokine secretion; it has fewer adverse effects than currently available drugs.

OBJECTIVE

In this study, we investigated the capacity of pimecrolimus to directly inhibit in vitro mediator release from human skin mast cells and basophils.

METHODS

Purified cutaneous mast cells or basophil-containing peripheral blood leukocytes were obtained from healthy human donors and preincubated with pimecrolimus (0.1 nmol/L to 1 micromol/L) in the absence or presence of its specific antagonist (rapamycin), cyclosporin A (100 nmol/L to 1 micromol/L), or dexamethasone (1 micromol/L) and then stimulated with anti-IgE or with calcium ionophore A23187 plus phorbol myristate acetate. Cell supernatants were kept for analysis of histamine, tryptase, LTC4, and TNF-alpha.

RESULTS

Pimecrolimus caused a strong and dose-dependent inhibition of anti-IgE--induced release of histamine from mast cells and basophils (maximally 73% and 82%, respectively, at 500 nmol/L pimecrolimus) and of mast cell tryptase (maximally 75%) and a less pronounced inhibition of LTC4 (maximally 32%) and of calcium ionophore plus phorbol myristate acetate--induced mast cell TNF-alpha release (90% maximum at 100 nmol/L pimecrolimus). In contrast, inhibition achieved during mast cell histamine release was maximally 60% with cyclosporin A and only 28% with dexamethasone.

CONCLUSION

These data demonstrate a marked inhibitory capacity of pimecrolimus on mediator release from human mast cells and basophils with a potency exceeding that of cyclosporin A and dexamethasone. Pimecrolimus might thus be expected to be effective in the treatment of mast cell-- and basophil-dependent diseases.

Immunotherapy in atopic dermatitis

Atopic dermatitis (AD) is a common inflammatory disease involving the skin and often other organs and systems, mainly respiratory. A definitive general consensus on the AD pathogenesis has not yet been established, however several lines of evidence suggest that T-cells play a crucial role in priming AD early-stage lesions. Main topics involved in the disease pathogenesis have been reviewed, which considered the concept of local and systemic haemopoietic events as important contributors to allergic inflammation, a concept now achieving great acceptance. The recently recognised atopic nature of the skin inflammation in AD has raised increasing interest for treatment with allergen-specific immunotherapy. However, we only found eight studies using specific immunotherapy (SIT) in AD, two double-blind, placebo-controlled (DBPC) and six observational. One controlled and five observational reported favourable outcomes. The one unique study providing negative results was flawed by the ineffective oral route of extract administration. Despite being encouraging, the reported results do not allow definitive conclusions based on meta-analytic techniques because the amount and quality of information in the literature is not sufficient. The highly promising sub-lingual immunotherapy (SLIT) is discussed with its potential capability of controlling not only the skin lesion severity but also its capability of preventing the development of atopic dermatitis into asthma.