Prospective, Randomized, Double Blind Comparative Study on the Use of Two Creams in Xerosis Atopic Probands
Condition: Atopic Dermatitis
MeSH terms: Dermatitis
Study type: Interventional

Summary: 
      Atopic dermatitis (AD), a chronic and relapsing inflammatory skin disease, is associated with
      elevated IgE levels and Th2 responses. It is currently believed that non-pathogenic bacteria
      modulate intestinal immune responses avoiding the development of allergic diseases. However,
      effects of oral probiotics on AD could not be reproduced in all studies and direct
      immuno-modulation of the skin associated immune response by non-pathogenic bacteria has not
      been investigated so far. We therefore performed a double blind placebo controlled clinical
      study on the effects of an ointment containing 5% extracts of the non-pathogenic bacteria
      Vitreoscilla filiformis on AD. Seventy-five AD patients (6-70 years of age) were randomized
      to receive either Vitreoscilla filiformis ointment 5% or vehicle ointment daily for 30 days.
      Efficacy evaluations, including the "Score of Atopic Dermatitis" (SCORAD), transepidermal
      water loss, assessement of microflora, and the patient assessment of itch and loss of sleep
      occurred at baseline, day 15, and day 29.
    

Detailed description: 
      Atopic dermatitis (AD) is a chronically relapsing inflammatory skin disease and often
      coexists with other atopic diseases, such as allergic rhinitis, conjunctivitis and asthma
      (Biedermann and Röcken 1999, Biedermann et al. 2001, 2004, 2006; Leung et al., 2000, 2003a,
      2003b). Even though the immune pathology of AD is not precisely understood, today the new
      concept of atopic dermatitis pathology is based on a large set of data. In most patients with
      AD, dry skin and dysfunction of the epidermal barrier is found. As an important prove of
      concept, the loss of function mutation of the epidermal protein filaggrin impairing skin
      barrier function was found and can be detected in about 15% of kaukasian AD patients (Palmer
      et al., 2006). As a consequence, patients with AD are predisposed to develop sensitizations
      dominated by a Th2 immune phenotype (Hudson, 2006).

      Independently of the filaggrin study, it was demonstrated earlier that a disrupted barrier
      function of the stratum corneum is present in atopics not only in involved skin, but also in
      uninvolved dry skin facilitating permeation of various environmental substances into the skin
      (Berardesca et al., 1990; Werner et al., 1985; Watanabe et al., 1991; Loden et al, 1992). As
      a biomarker, an increased level of transepidermal water loss (TEWL) can be demonstrated
      (Tagami et al., 1985; Ghadially et al., 1996). Various functional and morphological studies
      on atopic xerosis that clinically appeared without inflammation demonstrated that cellular
      inflammation is already present in atopic skin and a key and initial step in the development
      of atopic dermatitis (Watanabe et al., 1991; Uehara et al., 1984). In fact, barrier
      dysfunction, atopic immune dysregulation, and atopic dermatitis pathogenesis are not
      independent events, but closely linked (Biedermann 2006; Hudson 2006). Th2 lymphocytes
      dominate the atopic immune phenotype and are the underlying cell type responsible for the
      induction if IgE antibodies (Biedermann et al. 1999, 2004). Barrier dysfunction predisposes
      for the development of Th2 lymphocytes and Th2 cells are the first cell type invading atopic
      skin initiating inflammation and the inflammatory vicious circle of inflammation (Biedermann
      2002; 2004; Lametschwandtner et al. 2004; Günther et al. 2005). Next to Th2 lymphocytes, in
      atopic dermatitis skin lesions, infiltrates of eosinophils and cells of the mononuclear
      phagocyte lineage are found.

      The altered skin structure of people with atopic predisposition allows increased penetration
      of allergens and irritative substances (Roll et al., 2004; Hudson 2006). Many studies have
      shown that the extent of S. aureus colonization correlates with AD disease activity (Cho et
      al., 2001; Biedermann 2006). In more than 90% of AD patients, a massive skin colonization
      with S. aureus (up to 107cfu/cm2 of lesional skin) can be found (Matsui et al., 2000). A
      prerequisite for bacterial colonisation are the genuine barrier dysfunction, mechanical
      disruption of the barrier and trigger of inflammation (scratching), alkaline pH, decreased
      IgA secretion through sweat production, predominant Th2 cells inhibiting anti-infectious
      immune responses, and reduced antimicrobial peptides, all representing important
      pathophysiological features leading to the disruption of the primary skin defense system
      (Biedermann et al. 2001; Biedermann&Röcken 2001,; Biedermann et al. 2002; Biedermann 2006;
      Howell, 2005; Rieg 2005).

      Among several microbes colonising the skin, the bacterium Staphylococcus aureus (S. aureus)
      may play the most important role in the pathogenesis of dermatitis of atopic people
      (Biedermann 2006). This colonization is observed not only in the involved inflammatory skin
      but also in the non involved dry skin. The ratio Staphylococcus aureus / Staphylococcus
      epidermidis is inverse in comparison to healthy skin. Many studies have shown that the extent
      of S. aureus colonization correlates with AD disease intensity (Cho et al., 2001).

      Reduced expression of antimicrobial peptides was demonstrated for AD skin and favours
      colonization with S. aureus (Ong et al. N. Engl. J. Med. 2002; Howell et al.. Immunity.
      2006;24:341-8; Rieg et al. JI 2006). In addition, dry skin may by itself allow colonization
      with bacteria such as S. aureus. Decreased levels of sphingosine, which has antimicrobial
      properties and the fact that S. aureus itself stimulates the hydrolysis of ceramides by
      bacterial derived ceramidase in atopic skin add the dysfunction of the immune barrier in AD
      (Arikawa et al., 2002; Kita et al, 2002). The cell membrane of S. aureus contains adhesins
      for epidermal and dermal laminin and fibronectin allowing attachemment of S. aureus. to the
      skin and these docking positions for S. aureus are uncovered in lesional skin (Cho et al,
      2001). The precise mechanism by which S. aureus gains access to the dermis is unknown, but it
      is suggested that again IL-4, produced by T helper type 2 cells, induces fibronectin
      synthesis, which in combination with plasma exsudation of fibrinogen, allows S. aureus to
      bind to the skin. Moreover, S. aureus is able to encase itself in a kind of biofilm composed
      of a hydrated matrix of polysaccharides (glycocalix) and proteins, which supports cell
      adhesion (Akiyama et al., 2003). After colonization, S. aureus contributes to skin
      inflammation e.g. by secreting toxins and an array of so called pathogen associated molecular
      pattern (PAMP) that bind their pathogen recognition receptors such as Toll- like receptors
      and directly triggering inflammation (Biedermann 2006). Moreover, S. aureus PAMPs also
      influence T cell mediated skin inflammation by indirectly regulating skin homing of T cells
      and orchestrating chronic inflammation in AD skin (Biedermann 2006; Biedermann et al. 2006).

      Vitreoscilla filiformis (Vf) (ATCC15551) used in this study is a non-photosynthetic,
      non-fruiting gliding bacteria as defined according to the classification of Bergey's (1989).
      This filamentous bacterium belongs to the order of Beggiatoales. It is a micro-organism found
      in sodic sulphuretted thermal springs recognized for their local anti-pruriginous and
      anti-inflammatory properties.

      The micro-organism Vitreoscilla filiformis (Vf) was cultivated on a defined and sterile
      medium, expanded and isolated to constitute a biomass called "pure extract of thermal
      plankton". The term plankton describes the zooplankton (chemiotrope microorganisms) in
      contrast to the phytoplankton (phototrope microorganisms). At the end of culturing, the
      biomass is concentrated by stabilized centrifugation and autoclaved.

      The technical preparation is a sterile aqueous suspension of the plankton. In vitro studies
      show that this plankton supports the production of collagen by fibroblasts and reinforces the
      antioxidants systems; it prevents Langerhans cell alterations (reconstructed skin or
      organotypic skin culture) exposed to UVB. It exhibits non-specific immunomodulatory effects
      on cellular immunity and in particular on macrophages (Patent US, 6,190,671 B1; US, 6,242,229
      B1; WO-94/02158).

      Preclinical studies showed that this extract has anti-inflammatory activities (decreases ear
      oedema after acid arachidonic treatment and modulates contact hypersensitivity reaction with
      oxazolone). Moreover, this new compound promotes healing of epidermis and dermis (scaring
      following suction blister or following incision in preclinical studies; Patent US, 6,190,671
      B1). Therefore, this new compound promises to alleviate infections usually found on the skin
      after skin burning, protects skin against ultraviolet alterations and displayss moisturizing
      properties for the skin.

      Clinical trials showed that the bacterial extract Vitreoscilla filiformis is effective
      against acne and seborrhoeic dermatitis and promotes moisturization of the skin (studies in
      Seoul, Korea and in Nice, France and patent FR-2,283, 223) and has been shown to be
      beneficial for sensitive skin (clinical trial by Dr Desruelle F in Nice, France) Moreover, a
      randomized, double-blind, placebo-controlled trial with a formulated 5% extract of
      Vitreoscilla filiformis on symmetric active lesions of AD according to a split-body design
      was performed with Prof. J. F. Nicolas in Lyon, France.

      In this study, the treatment (applied twice daily) with the cream containing 5% Vitreoscilla
      filiformis extract was found to be safe and well tolerated. Moreover, this extract
      significantly alleviated AD in older children (from 7 years old) and adults compared with
      vehicle treatment (p=0.008; Wilcoxon signed ranks test). The therapeutic effects of the
      extract were observed within the second week of the application and steadily increased
      thereafter. This effect of the cream containing 5% Vitreoscilla filiformis extract appeared
      to have a rapid onset especially in regard to pruritus as demonstrated using the mEASI index.
      Paired testing confirmed a significant difference in the decrease of pruritus on the 5%
      Vitreoscilla filiformis extract treated side at day 28 (p=0,046, Wilcoxon exact signed ranks
      test). (Gueniche et al. 2006).

      Our task was to perform a double blind randomized prospective study comparing 5% Vitreoscilla
      filiformis extract (cream B) whith its vehicle (cream A) including measurements of biometric
      changes occurring during the use of the two creams.

      During the study biometrical and clinical measurements including the transepidermal water
      loss, the qualification and quantification of skin microflora and the clinical evaluation of
      the skin findings before, during and after the use of the creams was documented. Further the
      proband's experiences with the use of the creams were assessed. Biometric variables of the
      skin are determined before, during and after the use of cream A and cream B.

      The transepidermal water loss as biometrical value was estimated to assess the skin barrier
      function at all visits.

      We evaluated if topical application of cream A and cream B influenced the microflora of skin
      of atopic volunteers. Qualification and quantification of several bacteria (S. aureus, S.
      epidermis, P. acnes, Streptococci, E. coli) was performed before, during and at the end of
      the study period.

      In addition, the intensity of pruritus and the clinical aspect of the skin was assessed.

      At the end of the study each volunteer filled out a questionnaire asking about oiliness,
      distribution, consistency and adsorption of the creams.
    

Intervention name(s): vitreoscilla filiformis cream
Intervention type(s): Drug
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double
Primary purpose: Treatment
Keywords: Vitreoscilla filiformis extract; SCORAD; pruritus; microflora; TEWL