Title of Invention

STABILIZED HETEROGENEOUS MATRIX SYSTEM CONTAINING ENZYMES

Abstract

The present invention is directed to a formulation of heterogeneous matrix system for thestabilazaion of enzyme durimng processimng, on stroage and for modified release of enzyme, specfificallu, this inveniton relates to a heterogeneous matrix system in the form of granules, tablet or powder comprising of (a) lipid and stabilizer maintained in the vicinity of enzme(s), and optionally (b) active and /or inactive ingredients processed by suitable technique.

Full Text

FORM 2 THE PATENT ACT 1970 (39 of 1970) & The Patents Rules, 2003 COMPLETE SPECIFICATION (See section 10 and rule 13) 1. TITLE OF THE INVENTION: "Stabilized heterogeneous matrix system containing enzymes" 2. APPLICANT (S) (a) NAME: ADVANCED BIOCHEMICALS LIMITED (b)NATIONALITY: Indian Company incorporated under the Indian Companies ACT, 1956 (c) ADDRESS: Above Navneet Motors, Gokul Nagar, P. O. Box 182, Thane(W) 400 601. Maharashtra, India 3. PREAMBLE TO THE DESCRIPTION The following specification describes the invention and the manner in which it is to be performed. Field of invention: This invention relates to a heterogeneous matrix system comprising at least one lipid and stabilizer maintained in the vicinity of enzyme(s) which provides stability to the enzyme formulation. The invention may be formulated into powder, granules or tablet form. Further the invention may optionally comprise active and/or inactive ingredients processed by suitable technique. Background and Prior art: The stability of bioactive molecules such as enzymes and proteins remains a critical issue in biotechnology and pharmaceutical dosage forms. Loss of catalytic activity of bioactive molecules due to high temperature, pH and other denaturing influences is one of the most important concerns for commercialization and industrial application of the enzymes. Both storage and operational stabilities affect the usefulness of enzyme-based products. Storage stability, or shelf life, refers to maintenance of catalytic abilities of the enzyme in the period between manufacture and eventual use. Operational stability describes the persistence of enzyme activity during a process. Immobilization of bioactive molecules can give notable stability and generally prevent loss of activity. Enzymes are usually processed by the spray drying or the freeze-drying technique. The commonly used method for preparing solid protein pharmaceuticals is lyophilization (freeze-drying). However, this process generates a variety of freezing and drying stresses, such as solute concentration, formation of ice crystals, pH changes, etc. All of these stresses can denature proteins to various degrees. It has been shown that many additives, such as sugars, certain amino acids, some amines, and glycerol, stabilize proteins against these stresses during freezing and drying processes. Still, in many cases the use of these additives is insufficient to stabilize proteins completely. Even after successful lyophilization, the long-term storage stability of proteins may still be very limited, especially at high storage temperatures. Most proteins are only marginally stable at neutral pH and room temperature and hence are readily denatured by increasing (occasionally decreasing) the temperature, pressure, and by pH changes. Additionally, freeze dried products are very prone to absorb moisture when subjected to further processing in different formulations. Spray-drying technique is preferred over the freeze drying as it has low cost and good scale-up potential. In order to produce stable, storable enzymes, drying is one possibility. Indeed, removal of water reduces the movement freedom of the protein molecules and thus inhibits conformational changes leading to activity loss. But, spray-drying technique does not completely remove water. Stabilizing an enzyme normally means suppressing the unfolding of the protein and retaining the catalytic activity. The most important methods for stabilizing enzymes are modification of the protein structure by direct site mutagenesis and binding the biomolecule to polymeric carriers. But these approaches are not so feasible for the industrial (scale-up) application for the development of solid dosage form. Different approaches have been utilized for the stabilization of the enzyme in the solid dosage form, which include use of stabilizers, use of additives that increase thermostability of the enzymes, novel dosage forms (e.g. nanosphere), different coating layers (Coated granules WO 9723606) etc., but among these very few have a scale up potential. Many thermoelastic additives are used for the stabilization of enzyme in the tablet form e.g. Carrageenan. These agents can be tableted very easily under low pressure and at the same time show significant elastic recovery, due to this they can be expected to store less stress in the tablet and to embed the enzyme softly. Bioactive materials such as enzymes are reported in the tablet form for textile applications (US20030171238). This patent describes the use of effervescent material in combination with the enzyme for the textile and pulp industry. The tablet weight described in this is l gm to 100 gm, which is not feasible for the therapeutically active enzymes. In this patent application, the stability of the enzyme during compression and on storage is not mentioned. Enzymes are preferably delivered in the solid dosage form. In the solid dosage form, tablets are the suitable dosage form for application of these materials because enzymes are formulated in the dry state. The limited stability of enzymes during long-term storage has been attributed to the deleterious effects of moisture and microbial contamination due to moisture present in the granules or tablet. Tablet can be prepared by the dry granulation, wet granulation or direct compression. Also, in the wet granulation the residual moisture in granules provides mobilization to the enzyme and this leads to loss of activity. To avoid the water for granulation many solvents have been tried for the granulation, but water-miscible solvents are, in many cases, more problematic than hydrophobic solvents as regards protein stability. This is because hydrophilic solvents, unlike their hydrophobic counterparts, can remove the essentially bound water from the surface of the enzyme molecule. These hydrophobic solvents can not be used as a vehicle for binder due the residual volatile impurities. In case of direct compression or dry granulation the pressure applied to make the tablet or slug is more as compared to pressure required for granules prepared by wet granulation. The pressure, heat and environmental moisture are the major factors that affect the stability of enzyme during processing as well as during storage. Tablet dosage form can be prepared by wet granulation, dry granulation, direct compression or combination of these. Tablet containing enzymes such as amylases, proteases, lipases, invertases, papain, pepsin, pancreatin etc. have been described long ago in the patent US 3515642. In this invention sorbitol has been used for the stabilization processed by freeze-drying and spray drying. Also this invention utilizes the aqueous and non-aqueous solvent for the processing. But use of solvents has its own disadvantages and effects on enzyme stability. WO9500121 discloses production of a directly compressible enzyme powder by mixing a liquid enzyme preparation with a suitable carrier, using the principle of wet granulation technique, which can then be compressed to get a tablet. The powder has moisture content at most 10%. This high level of moisture may provide mobilization to the enzyme, and thus stability of enzyme is doubtful. Also the carrier used for this purpose must be able to absorb liquid. WO 9723606 teaches that repeated scavenger layers and special coatings are necessary to produce stable enzyme granules. Practically this invention is time consuming; process is complex due to number of coating steps and expensive due to four different coating layers of the material. This invention deals with only delayed release of the enzyme. Due to compaction pressure the losses of activity up to 50% has been reported for the different enzymes (C L D Teng, Pharm Res., 5, 1988, 776-780). This operational stability has become a serious issue for the commercialization of the enzyme product. Many additives have been reported to increase the thermostability and in some cases even activity of the enzymes like salts, polyols (polyethylene glycol, glycerol), dextran, bovine serum albumine, polyethylenimine, polyelectrolytes, organic osmolytes (e.g. betaine), organic solvents (isooctane, cyclohexane, chloroform, benzene), sugars (e.g. lactiol, mannitol, sorbitol, xylitol, inositol, erythritol) (US 3515642). There are few reports where lipidic materials such as glyceryl monooleate have been used for protection of peptide molecules such as insulin and serratiopeptidase (Paradkar et al.). Enzyme loaded in lipid powder has been used in the preparation of dough in baking industry for achieving release at specific temperature (WO 0219828). The release of the enzyme is dependent on the temperature and the activity of the enzyme which is utilized in the system only. Lipidic pellets containing enzymes have been used in animal feed (WO 9212645). The limitation of this invention is that the enzyme(s) are stabilized only when they are coated with the coating agent at least 1%, preferably 15-35%. Controlled release for about five days was obtained by using implants of enzyme in glyceryl palmitostearate (T. Pongjanyakul et al, UP, 271 53-62, 2004). But no attempts have been made to achieve improved storage and operational stability of enzyme using heterogeneous lipid matrix, especially in the tablet form. Object of invention The primary objective of the present invention is to develop a heterogeneous matrix system for improved stability of enzyme. Another objective of the invention is to present the heterogeneous matrix in a suitable form depending on its use. Additionally, the objective of the invention is to maintain it in the vicinity of the lipid and stabilizer. A further objective of the invention is to develop a heterogeneous matrix containing enzymes, optionally in combination with other active ingredients in the presence of pharmaceutically acceptable excipients. Other objects, aspects and advantages of this invention will become apparent from reading the remaining specification and claims. Summary of invention: The present invention provides a heterogeneous matrix system for improved stability of enzyme in different forms like powder, granules, tablet or any other suitable solid dosage form. The heterogeneous matrix system in the form of granules, tablet or powder comprises (a) lipid and stabilizer maintained in the vicinity of enzyme(s), and optionally (b) active(s) and/or inactive ingredients processed by suitable technique. The enzymes may be of any source, any class. The heterogeneous matrix system maintains the enzyme preferably in the vicinity of the lipid and stabilizer. Additionally, heterogeneous matrix system of the present invention may modify the release of the said enzyme. Brief description of drawings: Figure 1: Heterogeneous matrix granules containing enzyme, stabilizer, lipid and optionally additives. Figure 2: Heterogeneous matrix tablet containing (i) enzyme, stabilizer, lipid and optionally additives and (ii) actives and/or inactives. Figure 3: Heterogeneous matrix tablet containing (i) active and/or inactive and (ii) enzyme, stabilizer, lipid and optionally additives. Figure 4: Comparative stability data Detailed description of invention: The present invention provides a stabilized heterogeneous matrix system of enzyme in a solid dosage form. This heterogeneous matrix system essentially comprises an intimate admixture of enzyme, stabilizer, and lipid and optionally additive(s).Heterogeneous matrix system can be presented in the form of granules, tablet or powder. Heterogeneous matrix system claimed in this invention stabilizes the enzyme during processing like compression and during storage. The heterogeneous matrix system can be presented in the tablet dosage form with the other ingredients as such or processed by suitable technique. Other ingredients may be active, inactive or mixture thereof as per requirement for tablet preparation. The heterogeneous matrix system can be prepared by a suitable method. These methods include the simple mixing, melt granulation, melt extrusion, melt pelletization, melt solidification, fluid bed granulation, spray granulation, melt high-speed mixer granulation, melt fluidized bed granulation and melt tumbling fluidized bed granulation. The preparation technique used avoids the different steps responsible for the loss of the enzyme activity mainly drying. The preferred method of the present embodiment is melt granulation. General process of melt granulation to obtain the lipidic phase of the heterogeneous system comprises following steps: a. The stabilizer and enzyme powder were mixed thoroughly in a suitable mixer for sufficient time to obtain a uniform mixture and sieved through a suitable sieve or the two were sifted simultaneously and then mixed in a mixer. b. The lipid powder or molten lipid was added to the powder mass of step A with continuous stirring in a jacketed planetary or other suitable mixer. The mass was mixed to obtain a homogenous mass. c. The contents of the mixer were cooled below melting point of the lipid with simultaneous mixing, if molten lipid was added. d. The product of step C was processed further to obtain the agglomerates of suitable size. The heterogeneous matrix system can be presented in the tablet form with addition of the other ingredients. The other ingredients may be active or inactive or combination of both, used as such or in the form of granules or a combination of both. The granules may be prepared by dry granulation, wet granulation, or any method opted for the granulation. The heterogeneous matrix system has modified the release of the dosage form. The heterogeneous matrix system comprises an enzyme or combination of enzymes from any source mainly animals, microbial, genetically engineered or modified by protein engineering or a combination thereof. The enzymes include but are not limited to oxidoreductases such as peroxidases and glucose oxidases, hydrolases such as carbohydrases e.g. amylases, hemicellulases, cellulases, inulinaes, lactases and galactosidaes; proteases such as serratiopeptidase, fibinase, chitinase, trypsin, chymotrypsin; lipases and phytaes, isomerases such as glucose isomerases (or component there of) or a mixture thereof. The enzyme is present in the concentration range of 0.001 to 99 % w/w. The stabilizer used in the heterogeneous matrix system functions as an additive, provides stabilization to the enzyme, density, improves physical properties, improves micromeritic properties and enhances release or a combination of these. One or more than one stabilizers can be added depending on the design of the formulation. Preferably the stabilizer should be in intimate contact with the enzyme. The stabilizers not limiting to these example are magnesium trisilicate, magnesium silicate, magnesium carbonate, magnesium chloride, magnesium phosphate, magnesium oxide, magnesium sulphate, calcium oxide, calcium chloride, calcium phosphate, calcium carbonate, calcium sulphate, and salts of calcium, magnesium and potasium, chelating agents such as EDTA, nitrilotriacetic acid, buffering agent such as phosphates, citric acid etc. The additive(s) used in the heterogeneous matrix system could be active, could act as additive, provide stabilization to the enzyme, provide density, improve physical properties, improve micromeritic properties, enhance release or a combination of these. The additive(s) maybe optionally included in the composition. The additives could be active, not limiting to these examples are as anesthetic agents, ace inhibiting agents, antithrombotic agents, anti-allergic agents, antibacterial agents, antibiotic agents, anticoagulant agents, anticancer agents, antidiabetic agents, antihypotensive agents, antimicotic agents, antimigraine agents, antiparkinson agents, antirheumatic agents, antithrombins, , beta blocking agents, bronchospamolytic agents, calcium antagonists, cardiovascular agents, cardiac glycosidic agents, carotenoids, cephalosporins, contraceptive agents, cytostatic agents, diuretic agents, enkephalins, fibrinolytic agents, growth hormones, insulins, interferons, lactation inhibiting agents, lipid-lowering agents, lymphokines, neurologic agents, prostacyclins, prostaglandins, psycho-pharmaceutical agents, reproductive control hormones, sedative agents, vaccines, vasodilating agents, vitamins, immunosuppressive and immunoactive agents, antiviral and antifungal agents, antineoplastic agents, analgesic and anti-inflammatory agents, anti-epileptics, anesthetics, hypnotics, antipsychotic agents, neuroleptic agents, antidepressants, anxiolytics, anticonvulsant agents, antagonists, neuron blocking agents, anticholinergic and cholinomimetic agents, antimuscarinic and muscarinic agents, antiadrenergic and antiarrhythmics, antihypertensive agents, hormones, and nutrients. A detailed description of these and other suitable drugs may be found in Remington"s Pharmaceutical Sciences, 18th edition, 1990, Mack Publishing Co. Philadelphia, Pa. which is hereby incorporated by reference. The additives could be inactive not limiting to these examples are as cellulose, substituted cellulose, calcium carbonate, dicalcium phosphate, starches, lactose, modified food starches, dextrose, calcium sulfate, magnesium carbonate, magnesium stearate, stearic acid, polysorbates, lecithin, silicium dioxide, food glaze, talc, croscarmeilose sodium, povidone, gelatin. Additional inactive excipients, carriers, diluents, lubricants and adjuvants which may be used with the active-ingredient composition of this invention are disclosed in the Handbook of Food Additives (CRC Press), which is incorporated by reference herein in relevant part. The lipid(s) used in the heterogeneous matrix system could also function as additive, binder, and could provide stabilization to the enzyme. Lipid could provide density, improve physical properties, improve micromeritic properties, enhance release or a combination of these as in case of stabilizer. Either one lipid or a combination of lipids can be added depending on the design of the formulation. Preferably, the lipid(s) should be in intimate contact with the enzyme. This could help to protect the enzyme from the moisture, may immobilize the enzyme, may protect enzyme from stress during and after compression. The lipid may be saturated or unsaturated fatty acids or mixtures thereof; mono, di or triglycerides or mixtures thereof; waxes, or derivative thereof with a melting point between 1°C to 150°C, preferably between 20 °C to 100°C. Further the lipid may be present in the concentration range of 0.001 to 99 % w/w. The lipids may be saturated or unsaturated lipids in the liquid, semi-solid or solid form, used as such or processed. They may be preferably high melting fat or wax with a melting point between 30 °C to 100°C. The heterogeneous matrix system optionally comprises an excipient which may include nucleation and crystallization rate modifiers, viscosity modifiers, glass transition state modifiers, colouring agents, flavouring agents, preservatives, antioxidants, diluents, fillers, adsorbants, anticaking agents, lubricants, glidants, disintegrants, release rate modifiers, binders, coating polymers, plasticizers, buffering agent, chelating agents and such others, alone or in combination. The invention is further illustrated with the following examples. Example: Example 1: Heterogeneous matrix granules Proteases enzyme 50% w/w Magnesium trisilicate 5 % w/w Glyceryl behenate 45 % w/w Proteases enzyme and magnesium trisilicate were mixed well in the mixer and the melted lipid was added to the mix with continuous stirring. The mixture was allowed to cool and passed through desired sieve to get the granules. Results: Enzyme activity of the granules on storage was found to be satisfactory and stable. Example 2: Heterogeneous matrix tablet Proteases enzyme 6 %w/w Magnesium trisilicate 0.5% w/w Lactose 35 % w/w Microcrystalline cellulose. 50 % w/w Binder 3 % w/w Glyceryl behenate 5 % w/w The first two components were mixed well in the mixer, and the lipid in the melted stage added to the mix under stirring. The mixture was allowed to cool and passed through desired sieve to get the granules. The lactose and MCC were mixed well in the mixer, and the granulation was processed with addition of binder solution. The wet mass was passed through sieve and dried. The granules were mixed and compressed with desired weight. Results: Enzyme activity of the tablet during compression and on storage found to be satisfactory and stable. Example 3: Heterogeneous matrix tablet -Enzyme 6 % w/w (mix of proteasase enzymes from different sources) Magnesium trisilicate 0.5% w/w Lactose 35 % w/w Microcrystalline cellulose. 50 % w/w Binder 3 % w/w Glyceryl behenate 5 % w/w The first two components were mixed well in the mixer, and the lipid in the melted stage added to the mix under stirring. The mixture was allowed to cool and passed through desired sieve to get the granules. The lactose and MCC were mixed well in the mixer, and the granulation was processed with addition of binder solution. The wet mass was passed through sieve and dried. The granules were mixed and compressed with desired weight. Results: Enzyme activity of the tablet during compression and on storage found to be satisfactory and stable. Example 4: Heterogeneous matrix tablet Enzyme mix 6 %w/w (protease,amylase,lipase,cellulase) Magnesium trisilicate 0.5% w/w Lactose 35 % w/w Microcrystalline cellulose. 50 % w/w Binder 3 %w/w Glyceryl behenate 5 % w/w The first two components were mixed well in the mixer, and the lipid in the melted stage added to the mix under stirring. The mixture was allowed to cool and passed through desired sieve to get the granules. The lactose and MCC were mixed well in the mixer, and the granulation was processed with addition of binder solution. The wet mass was passed through sieve and dried. The granules were mixed and compressed with desired weight. Results: Enzyme activity of the tablet during compression and on storage found to be satisfactory and stable. Example 5: Heterogeneous matrix tablet with drug Proteases enzyme 6 % w/w Magnesium trisilicate 0.5% w/w Lactose 35% w/w Microcrystalline cellulose. 27.5 % w/w Diclofenac Sodium 22% w/w Binder 3 % w/w Glyceryl behenate 5 %w/w Protease and Magenisium trisilicate were sifted through sieve, mixed well for 10 min. The mix was granulated with molted Lipid. Cooled material was passed through sieve. Diclofenac Na, lactose and MCC mixed well. The mix was granulated with additional binder material. The granules were dried and passed through desired mesh. Both the granules were mixed well and compressed with suitable punches. Stability Chart: Product No Description Storage Conditions Example 1,2,3,4 Granules, Tablets Temp: 25°C±2°c % Releative Humidity:60%±5% Date of analysis Description Activity % initial Complies 106 One month Complies 105 Two month Complies 105 Three month Complies 102 We Claim, 1. A stabilized heterogeneous matrix system containing enzyme or combination of enzymes in the form of powder, granules, tablet or solid dosage form comprising a lipid and stabilizer maintained in the vicinity of enzyme(s) for stabilizing enzymes or combination of enzymes and optionally containing active/inactive pharmaceutical ingredients. 2. The heterogeneous matrix system as claimed in claim 1, comprising a lipidic and non¬lipids phase in an internal or continuous phase. 3. The heterogeneous matrix system as claimed in claim 1, wherein the lipid may be natural, semi-synthetic or synthetic, in the liquid, semi-solid or solid form. 4. The heterogeneous matrix system as claimed in claim 1, wherein the lipid is selected from saturated or unsaturated fatty acids or mixtures thereof; mono, di or triglycerides or mixtures thereof; waxes and derivatives thereof. 5. The heterogeneous matrix system as claimed in claims 1 and 4, wherein said lipid has a melting point between 1°C to 150°C, preferably between 20 °C to 100°C. 6. The heterogeneous matrix system as claimed in claim 1 wherein the lipid is present in the concentration range of 0.001 to"99 % w/w. 7. The heterogeneous matrix system according to claim 1, said stabilizer selected from magnesium trisilicate, magnesium silicate, magnesium carbonate, magnesium chloride, magnesium phosphate, magnesium oxide, magnesium sulphate, calcium oxide, calcium chloride, calcium phosphate, calcium carbonate, calcium sulphate, and salts of calcium, magnesium and potasium, chelating agents such as EDTA, nitrilotriacetic acid, buffering agent such as phosphates and citric acid. 8. The heterogeneous matrix system as claimed in claim 1 and 7, wherein said stabilizer is used in the concentration range of 0.001 to 50 % w/w. 9. The heterogeneous matrix system as claimed in claim 1 wherein, said enzyme or combination of enzymes is from any source mainly animals, microbial or genetically engineered or modified by protein engineering or a combination thereof. 10. The heterogeneous matrix system as claimed in claim 1 and 9, wherein said enzyme is selected from oxidoreductases such as peroxidases and glucose oxidases, hydrolases such as carbohydrases, amylases, hemicellulases, cellulases, inulinaes, lactases and galactosidaes; proteases such as papain, bromelain, serratiopeptidase, fibinase, chitinase, trypsin, chymotrypsin; lipases and phytaes, isomerases such as glucose isomerases or combination thereof. 11. The heterogeneous matrix system as claimed in claims 1, 9, and 10, wherein said enzyme is present in the concentration range of 0.001 to 30 % w/w. 12. The heterogeneous matrix system according to claim 1 comprising optionally an excipient which may include nucleation and crystallization rate modifiers, viscosity modifiers, glass transition state modifiers, colouring agents, flavouring agents, preservatives, antioxidants, diluents, fillers, adsorbants, anticaking agents, lubricants, glidants, disintegrants, release rate modifiers, binders, coating polymers, plasticizers, buffering agent, chelating agents and such others, alone or in combination. 13. A process for preparation of heterogeneous matrix system comprising the steps of: a) mixing the enzymes and Magnesium trisilicate in a mixer; b) adding melted lipid to the mix under stirring; c) allowing the mixture to cool; d) passing through desired sieve to get the granules; e) mixing lactose and microcrystalline cellulose and optionally with drug in a mixer; f) preparing granules by addition of binder solution; g) passing the wet mass through sieve and drying the granules h) mixing the granules of step d) with step g) and compressing to get tablet. Dated this 3rd day of Nov, 2005 Agent for the Applicant Dr. P. Aruna Sree

Documents:

1189-mum-2004-abstract(19-9-2007).doc

1189-mum-2004-abstract(19-9-2007).pdf

1189-mum-2004-abstract.doc

1189-mum-2004-abstract.pdf

1189-mum-2004-cancelled pages(19-9-2007).pdf

1189-mum-2004-claims(granted)-(19-9-2007).doc

1189-mum-2004-claims(granted)-(19-9-2007).pdf

1189-mum-2004-claims.doc

1189-mum-2004-claims.pdf

1189-mum-2004-correspodence.pdf

1189-mum-2004-correspondence(27-7-2006).pdf

1189-mum-2004-correspondence(ipo)-(13-3-2007).pdf

1189-mum-2004-correspondence(ipo).pdf

1189-mum-2004-description(granted).doc

1189-mum-2004-description(granted).pdf

1189-mum-2004-drawing(19-9-2007).pdf

1189-mum-2004-drawing.pdf

1189-mum-2004-form 1(3-11-2004).pdf

1189-mum-2004-form 1(4-11-2004).pdf

1189-mum-2004-form 18(27-7-2006).pdf

1189-mum-2004-form 18.pdf

1189-mum-2004-form 1[4-nov-2004].pdf

1189-mum-2004-form 2(cancelled).pdf

1189-mum-2004-form 2(granted)-(19-9-2007).doc

1189-mum-2004-form 2(granted)-(19-9-2007).pdf

1189-mum-2004-form 2(granted).doc

1189-mum-2004-form 2(granted).pdf

1189-mum-2004-form 2(provisional).pdf

1189-mum-2004-form 2(title page).pdf

1189-mum-2004-form 26(12-05-2004).pdf

1189-mum-2004-form 26(4-11-2004).pdf

1189-mum-2004-form 26.pdf

1189-mum-2004-form 3(4-11-2004).pdf

1189-mum-2004-form 3.pdf

1189-mum-2004-form 5(3-11-2005).pdf

1189-mum-2004-form 5.pdf

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