AU779692B2 - Pharmaceutical preparation containing nanosol - Google Patents

Pharmaceutical preparation containing nanosol Download PDF

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Publication number
AU779692B2
AU779692B2 AU75094/00A AU7509400A AU779692B2 AU 779692 B2 AU779692 B2 AU 779692B2 AU 75094/00 A AU75094/00 A AU 75094/00A AU 7509400 A AU7509400 A AU 7509400A AU 779692 B2 AU779692 B2 AU 779692B2
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AU
Australia
Prior art keywords
active substance
chitosan derivative
production
pharmaceutical preparation
charged
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
AU75094/00A
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AU7509400A (en
Inventor
Bodo Asmussen
Hans-Rainer Hoffmann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
LTS Lohmann Therapie Systeme AG
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LTS Lohmann Therapie Systeme AG
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Publication date
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Publication of AU7509400A publication Critical patent/AU7509400A/en
Application granted granted Critical
Publication of AU779692B2 publication Critical patent/AU779692B2/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00Medicinal preparations characterised by special physical form
    • A61K9/48Preparations in capsules, e.g. of gelatin, of chocolate
    • A61K9/50Microcapsules having a gas, liquid or semi-solid filling; Solid microparticles or pellets surrounded by a distinct coating layer, e.g. coated microspheres, coated drug crystals
    • A61K9/51Nanocapsules; Nanoparticles
    • A61K9/5107Excipients; Inactive ingredients
    • A61K9/513Organic macromolecular compounds; Dendrimers
    • A61K9/5161Polysaccharides, e.g. alginate, chitosan, cellulose derivatives; Cyclodextrin
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61JCONTAINERS SPECIALLY ADAPTED FOR MEDICAL OR PHARMACEUTICAL PURPOSES; DEVICES OR METHODS SPECIALLY ADAPTED FOR BRINGING PHARMACEUTICAL PRODUCTS INTO PARTICULAR PHYSICAL OR ADMINISTERING FORMS; DEVICES FOR ADMINISTERING FOOD OR MEDICINES ORALLY; BABY COMFORTERS; DEVICES FOR RECEIVING SPITTLE
    • A61J3/00Devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61PSPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P43/00Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/0004Preparation of sols
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/0004Preparation of sols
    • B01J13/0039Post treatment
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B82NANOTECHNOLOGY
    • B82YSPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y5/00Nanobiotechnology or nanomedicine, e.g. protein engineering or drug delivery

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  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Organic Chemistry (AREA)
  • Medicinal Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Epidemiology (AREA)
  • Dispersion Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Biomedical Technology (AREA)
  • Nanotechnology (AREA)
  • Optics & Photonics (AREA)
  • Physics & Mathematics (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Medicinal Preparation (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)

Description

Pharmaceutical Preparation Pharmaceutical preparations wherein an active substance is present bound to a carrier are known in the state of the art in great abundance. In the widest sense, the bond to the carrier can be understood to be purely mechanical; in a narrow sense, however, one makes use of the capacity of carrier substances to enter into special chemical or physicochemical interactions with the active substance or substances.
One category of such interactions are ionic attractive forces, which of course can only be made use of if active agent and carrier are at least partially present in a charged state. In pharmaceutical preparations, ionic bonds between active substances and carriers are used, inter alia, to preserve sparingly soluble active substances which have a low tendency of dissociation in water in their charged and molecular-disperse state, thereby obtaining a high dissolution rate. Apart from this, active agents are bonded to oppositely charged carrier polymers to enable a high active substance load of the preparation; this formulation technique is frequently used, for instance, in liposome preparations. A further variant which has been described are preparations wherein by way of the ionic bond to a charged polymer it is intended to achieve a controlled release of active substance. An example for this is the cough mixture marketed in Germany under the mark Codipront® which contains as active substance carrier complex an active substance base, Codeine poly(styrene, divinyl benzene)sulfonate, bonded to an acidic ion exchanger.
A special form of active agents bound to oppositely charged carriers are the so-called nanosols with gelatine or collagen hydrolysates as carriers, which are described by the firm of Alfatec-Pharma GmbH in various patents and published applications, e.g. in the documents DE 41 40 195, DE 41 40 178 and DE 41 40 179. Here, one makes use of the fact that it is easily possible to achieve the desired, isoionic state with charge equalization between carrier and active substance if gelatine or gelatine derivatives are used, thanks to the zwitterionic nature of the same, by means of a corresponding pH adjustment in the preparation. It is described that these nanosols can be used to advantage for the production of medicinal preparations both with rapid and with controlled active substance release.
However, these preparations have the disadvantage that the population has been uncertain for several years as to the possible risks of BSE infection and has increasingly been avoiding products containing gelatine, for example. Therefore, there is a need for preparations without gelatine or collagen derivatives which have the same advantages as, for example, the gelatinebased nanosols described.
S• The present invention provides a pharmaceutical preparation without gelatine or the like, for charged active substances, in which the active substance is present bonded to an oppositely charged carrier.
SThe present invention provides a process for the production of a solid pharmaceutical preparation comprising at least one at least partially charged active substance, which active substance is present in the form of a nanosol which is a sol containing particles with an average particle size of at maximum 1000 nrim, and in which the active substance is bonded to an oppositely charged chitosan derivative as a carrier, said process being characterized in that an aqueous sol is prepared from a negatively charged or zwitterionic, acidic chitosan derivative and an active substance having positive charge, by adding the active substance prior to or after dissolving the chitosan derivative or by uniting a solution of the chitosan derivative and an independently prepared solution for the active substance; 2a the chitosan derivative being selected according to the type and relative number of its charged groups and in coordination with the type and relative number of the positively charged groups of the active substance such that at a certain pH value an isoionic state or charge equalization between active substance and carrier is achieved in the preparation; the pH value of the aqueous sol is adjusted such that an isoionic state results, possibly with colloidal or nano-scale active substance particles precipitating; and, optionally, the thus-adjusted aqueous sol is dried.
It was surprisingly found that using chitosans as carriers it is possible to produce so-called nanosols wherein the active substance is present stabilized in a state almost isoionic with the carrier, and that these nanosols are highly suitable for the production of medicinal products.
eeo The preparation of the present invention contains according to Claim 1 at least one pharmaceutical active substance, which is at least partially present in a charged state, i.e. the active substance is capable of forming an ionic state and at least part of the active substance molecules are present in that ionic state.
For a definition of a nanosol, reference is made to DE 41 40 195.
Considered as chitosan derivatives in the spirit of the invention are all modified and unmodified deacetylation products of chitin which still possess a polyglucosamine base structure. The charge opposite to that of the active substance, which is demanded according to the present invention, refers to the net-charge of the carrier used.
Thus there may also be charges in the chitosan derivative that are like that of the active substance as long as they are overcompensated by the opposite charges.
In fact, in one of the preferred embodiments there is an active substance with a positive charge that is bonded in the nanosol to a chitosan derivative with negative total charge. Such a chitosan derivative may, for example, be a zwitterionic, partially sulfated chitosan.
In a further, also preferred, embodiment, the active substance is present in a negatively charged state and is bound in the nanosol to a positively charged chitosan derivative, i.e. in the most simple case to an unmodified chitosan. Here, too, an active substance may well be present in a partially undissociated form and may even possess some charges that are like that of the chitosan derivative as long as its net-charge is opposite, i.e. in this case negative.
Preferably, the active substance is present in the nanosol in a colloidal or nanoparticulate distribution, i.e. with an average particle size of at maximum about 500-1000 nm, as far as it is possible to detect a phase boundary between active substance and carrier phase at all. In particular, poorly soluble active agents can be incorporated in this way in pharmaceutical preparations from which they can be quickly released.
The preparations according to the present invention will as a rule contain further auxiliary agents which are commonly used in the pharmaceutics technology and are known to those skilled in the art. These active auxiliary agents may, for example, be further polymeric or non-polymeric carrier substances, but also stabilisers, surfactants, disintegration promoters, antioxidants, dyes, pigments, flavours, sweeteners or other taste-improving agents, binders, lubricants etc. In a preferred embodiment, the preparation contains a further polymeric carrier substance. This can be required, for example, in order to increase the loadability of the nanosol with active substance or in order to modify the release properties of the preparation. Appropriate formulation techniques are likewise known to those skilled in the art.
In accordance with the invention, the herein disclosed pharmaceutical preparations are used for making medicinal products or diagnostic agents. A preferred use of the preparation consists in the production of medicinal agents which are administered as capsules, tablets, powders or granulates, or, like instant preparations, are first dissolved or redispersed in water or another suitable liquid prior to being administered.
In a further preferred embodiment, the preparations are used for preparing medicinal products having controlled active substance release. To this end, they must generally be further modified, i.e. mixed with further auxiliary substances or enclosed by these. For instance, capsules or tablets containing a preparation according to the present invention can be coated with a polymeric film which controls the release of the active agent or agents. These and further techniques for producing medicinal products with modified or controlled release of active substance are known to those skilled in the art.
A preparation according to the present invention is basically produced in a multi-step process which can be varied if necessary or complemented by further steps.
Initially, a chitosan derivative is selected as carrier, taking into account the relative number and type of the charged groups of the active agent, which on account of the type and relative number of its charged groups is matched with the active substance in such a way that at a certain pH value an isoionic state or charge equalization can be achieved between active substance and carrier. This is generally the case if the net-charges of active substance and chitosan derivative are opposite and the calculated isoionic point is in a pH range that is physiologically acceptable and is not detrimental to the stability of the active substance.
In a further step, a colloidal aqueous solution is prepared from the chitosan derivative and the active substance, which on account of its polymer content and the viscosity resulting therefrom is a sol. It is of no importance here whether the active substance is added following or prior to dissolving the chitosan derivative, or whether a solution of the chitosan derivative and an independently prepared solution of the active substance are united.
In a further step, the pH of the aqueous sol is adjusted such that an isoionic state results. In the course of this pH shift a precipitation of the active substance may occur.
It has turned out here that the particles do generally not exceed the colloidal or nanoparticulate size range.
The sol which has been thus prepared and adjusted to an isoionic state can be dried in a further process step. For this purpose, conventional drying methods, but preferably drying methods applying no or only little heat such as freeze drying, may be used.

Claims (12)

1. Process for the production of a solid pharmaceutical preparation comprising at least one at least partially charged active substance, which active substance is present in the form of a nanosol, which is a sol containing particles with an average particular size of at maximum 1000 nm, and in which the active substance is bonded to an oppositely charged chitosan derivative as a carrier, said process being characterized in that an aqueous sol is prepared from a negatively charged or zwitterionic, acidic chitosan derivative and an active substance having positive charge, by adding the active substance prior to or after dissolving the chitosan derivative or by uniting a solution of the chitosan derivative and an independently prepared solution of the active substance, •the chitosan derivative being selected according to the type and relative number of its charged groups and in coordination with the type and relative number of the °positively charged groups of the active substance such that at a certain pH value an isoionic state or charge equalization between active substance and carrier is achieved in the preparation; the pH value of the aqueous sol is adjusted such that an isoionic state results, possibly with colloidal or nano-scale active substance particles precipitating; and, optionally, S. the thus-adjusted aqueous sol is dried.
2. Process according to claim 1, characterized in that a poorly soluble active substance is used.
3. Process according to any one of the preceding claims, characterized in that apart from the chitosan derivative, a further polymeric carrier substance is used.
4. Solid pharmaceutical preparation comprising at least one at least partially charged active substance, characterized in that the active substance is present in the form of 8 nanosol particles having a colloidal or nanoparticulate size distribution with an average particle size of at maximum 1000 nm, said active substance having a positive charge and being bonded to a negatively charged or zwitterionic, acidic chitosan derivative.
Solid pharmaceutical preparation according to claim 4, characterized in that the active substance is poorly soluble.
6. Solid pharmaceutical preparation according to claim 4 or 5, characterized in that it contains a further polymeric carrier apart from the chitosan derivative.
7. Use of a pharmaceutical preparation prepared according to a process according to any S.one of claims 1 to 3, or of a preparation according to any one of claims 4 to 6, for the production of a medicinal product. i
8. Use according to claim 7 for the production of a medicinal product for peroral application.
9. Use according to claim 7 or 8 for the production of a medicinal product which is administered as a powder, granulate, tablet or capsule.
Use according to any one of claims 7 to 9 for the production of a medicinal product which, for the purpose of administration, is dissolved or redispersed in a liquid.
11. Use according to any one of claims 7 to 10 for the production of a medicinal product having controlled active substance release.
12. Use of a pharmaceutical preparation prepared according to a process according to any one of claims 1 to 3 for the production of a diagnostic agent Dated this 8 h day of December 2004 LTS LOHMANN THERAPIE-SYSTEME AG HODGKINSON McINNES PAPPAS Patent Attorneys for the Applicant
AU75094/00A 1999-08-27 2000-08-14 Pharmaceutical preparation containing nanosol Ceased AU779692B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE19940794A DE19940794A1 (en) 1999-08-27 1999-08-27 Pharmaceutical preparation
DE19940794 1999-08-27
PCT/EP2000/007904 WO2001015669A1 (en) 1999-08-27 2000-08-14 Pharmaceutical preparation containing nanosol

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AU7509400A AU7509400A (en) 2001-03-26
AU779692B2 true AU779692B2 (en) 2005-02-03

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AU75094/00A Ceased AU779692B2 (en) 1999-08-27 2000-08-14 Pharmaceutical preparation containing nanosol

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EP (1) EP1206253B1 (en)
JP (1) JP2003508423A (en)
KR (1) KR100624499B1 (en)
CN (1) CN1181815C (en)
AR (1) AR025392A1 (en)
AT (1) ATE279180T1 (en)
AU (1) AU779692B2 (en)
BR (1) BR0013563A (en)
CA (1) CA2382359C (en)
CZ (1) CZ301704B6 (en)
DE (2) DE19940794A1 (en)
DK (1) DK1206253T3 (en)
ES (1) ES2231265T3 (en)
HK (1) HK1047037B (en)
HU (1) HU227609B1 (en)
IL (2) IL148220A0 (en)
MX (1) MXPA02002048A (en)
NZ (1) NZ517541A (en)
PL (1) PL203860B1 (en)
PT (1) PT1206253E (en)
RU (1) RU2256440C2 (en)
TR (1) TR200200520T2 (en)
TW (1) TWI267384B (en)
WO (1) WO2001015669A1 (en)
ZA (1) ZA200201135B (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100638041B1 (en) * 2003-12-24 2006-10-23 주식회사 삼양사 A nanoparticle composition of a water-soluble drug for oral administration and a preparation method thereof
KR100767336B1 (en) * 2006-04-19 2007-10-18 서평원 Chitin/chitosan based functional organic-inorganic composite material and method for producing the same and use thereof
US9161901B2 (en) 2008-02-21 2015-10-20 University Of South Florida Nanoparticle targeted drug delivery to the lungs using extra-testicular Sertoli cells
UA90013C2 (en) 2008-03-19 2010-03-25 Давид Анатолійович Нога Pharmaceutical composition containing insulin and process for the preparation thereof
PL220269B1 (en) 2008-04-21 2015-09-30 Przedsiębiorstwo Produkcji Farmaceutycznej Hasco Lek Spółka Akcyjna Composite carrier of powdered medicines, method of production the medicine carrier and equipment for production of particles of composite carrier
DE102009024542A1 (en) * 2009-06-10 2010-12-16 Arivine Pharma Ag Compositions based on chitosan oligosaccharides

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5474989A (en) * 1988-11-11 1995-12-12 Kurita Water Industries, Ltd. Drug composition
DE4140195C2 (en) * 1991-12-05 1994-10-27 Alfatec Pharma Gmbh Pharmaceutical nanosol and process for its manufacture
US6184037B1 (en) * 1996-05-17 2001-02-06 Genemedicine, Inc. Chitosan related compositions and methods for delivery of nucleic acids and oligonucleotides into a cell
CA2228251A1 (en) * 1996-06-11 1997-12-18 Zonagen, Inc. Chitosan drug delivery system
ES2114502B1 (en) * 1996-07-29 1999-07-01 Univ Santiago Compostela APPLICATION OF NANOPARTICLES BASED ON HYDROPHILIC POLYMERS AS PHARMACEUTICAL FORMS.
DE19845246A1 (en) * 1997-12-18 1999-06-24 Henkel Kgaa Vitamin E compositions
WO1999036090A1 (en) * 1998-01-16 1999-07-22 The Johns Hopkins University Oral delivery of nucleic acid vaccines by particulate complexes

Also Published As

Publication number Publication date
CA2382359A1 (en) 2001-03-08
JP2003508423A (en) 2003-03-04
PT1206253E (en) 2005-02-28
EP1206253A1 (en) 2002-05-22
HUP0300345A3 (en) 2009-01-28
NZ517541A (en) 2002-08-28
TR200200520T2 (en) 2002-06-21
ES2231265T3 (en) 2005-05-16
AU7509400A (en) 2001-03-26
PL354572A1 (en) 2004-01-26
CN1181815C (en) 2004-12-29
WO2001015669A1 (en) 2001-03-08
DE19940794A1 (en) 2001-03-01
RU2256440C2 (en) 2005-07-20
DE50008259D1 (en) 2004-11-18
AR025392A1 (en) 2002-11-27
HK1047037B (en) 2005-03-24
CZ301704B6 (en) 2010-06-02
HU227609B1 (en) 2011-09-28
TWI267384B (en) 2006-12-01
KR20020031416A (en) 2002-05-01
CN1370065A (en) 2002-09-18
ATE279180T1 (en) 2004-10-15
HUP0300345A2 (en) 2003-09-29
PL203860B1 (en) 2009-11-30
CA2382359C (en) 2008-03-18
HK1047037A1 (en) 2003-02-07
MXPA02002048A (en) 2002-08-20
CZ2002653A3 (en) 2002-05-15
IL148220A0 (en) 2002-09-12
DK1206253T3 (en) 2005-01-31
EP1206253B1 (en) 2004-10-13
ZA200201135B (en) 2002-08-28
BR0013563A (en) 2002-07-09
KR100624499B1 (en) 2006-09-18
IL148220A (en) 2009-05-04

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