Drug – bio-affecting and body treating compositions – Solid synthetic organic polymer as designated organic active... – Aftertreated polymer
Reexamination Certificate
2001-02-01
2002-10-22
Page, Thurman K. (Department: 1615)
Drug, bio-affecting and body treating compositions
Solid synthetic organic polymer as designated organic active...
Aftertreated polymer
C424S422000, C424S423000
Reexamination Certificate
active
06468521
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to stabilised compositions having antibacterial, anti-viral and/or antifungal activity, to a method of producing such compositions, medical devices having a coating comprising such compositions, and the use of the stabilised compositions for producing a wound dressing, an ostomy appliance, an incontinence device, other medical devices or hydrophilic coatings.
BACKGROUND OF THE INVENTION
The antiseptic activity of silver compounds is a well known property which has been utilised for many years. The bacteriostatic and fungistatic effect is caused by the silver ion and a simple compound which has been used clinically is for instance silver nitrate. Silver nitrate in concentrations of 0.5-1% in water shows disinfectant properties and is used for preventing infections in burns or for prophylaxis of neonatal conjunctivitis. For another silver compound, silver sulfadiazine, the antibacterial effect of the sulfadiazine molecule is further enhanced by the complexing with the disinfecting silver ion. In contrast to the silver nitrate, the solubility of the silver sulfadiazine complex is low and hence, both of the two active parts are only present in solution in low concentrations but may be present over a longer period of time before being washed out at site to be treated. The silver sulfadiazine is intensively used in the treatment of wounds, in particular bums, under the trademarks Silvadene® and Flamazine®. Silver-protein-combinations are yet other antiseptic formulations which have been used in low concentrations as eye drops.
Bacteriostatics based on the silver ion are further used in various medical devices. One example of such application is the use in the wound dressing sold by Johnson & Johnson under the trademark Actisorb® which is an activated charcoal cloth dressing. Another example is the wound dressing sold under the trademark EZ-Derm by Genetic Laboratories which dressing is a modified pigskin impregnated with a soluble silver compound intended for treatment of burns. A number of patents discloses compositions or devices showing antiseptic properties based on contents of silver compounds. EP 272 149 B1 discloses a medical dressing of the ‘hydrocolloid’ type containing and releasing active components. Silver chloride is a specific antiseptically acting compound mentioned in this patent.
A specific advantage in using the silver ion as bacteriostatic agent is the general lack of formation of bacterial tolerance to the compound. This is in contrast to many types of antibiotics. However a major drawback when using ionic silver for bacteriostatic purposes is the reduction of the ion to free silver which results in dark stainings. Such staining has been reported to give potentially permanent pigmentation of the skin, the so-called argyria. It is commonly recognised that silver containing compounds will discolour by influence of light and or heat, and it will often be found that sterilisation by radiation may lead to a unsatisfactory change of the colour of a composition in which it is comprised, irrespective of the use in a solution, cream or gel or a medical device. Furthermore, such antibacterial compositions are often intended used in connection with medical or cosmetic products under circumstances where a discoloration is very unfortunate and potentially precluding for the use.
Recently, principles of antimicrobial metal-based compositions being photo stable, have been disclosed in U.S. Pat. No. 5,326,567 to Capelli and in U.S. Pat. No. 5,429,819 to Oka. In U.S. Pat. No. 5,326,567 a ‘host-guest’ relationship between silver ions and acyclic polyethers is accomplished through the use of excess of halide ions. In U.S. Pat. No. 5,429,819 is disclosed a photo-stable composition comprising a complex of the silver ion with a thiosulphate salt carried on a porous particulate carrier. In U.S. Pat. No. 3,911,115 (DE patent No. 22 60 536) a cycloheptaamylose (&bgr;-cyclodextrin) alkanol amine compound is claimed to posses stabilisirc effects on silver. However, in praxis the cycloheptaamylcse alkanol amine complex is not effective in preventing discolouring and furthermore, for medical purposes it is disadvantageous to introduce an alkanol giving rise to formation of a toxic carrier complex for the silver as the alkanolamines generally are known as irritants and moderate toxic compounds having numerous potential side effects (Patty's Industrial Hygiene and Toxicology, Vol. II, Part B, 4th ed. 1994).
It is commonly recognised that compounds containing silver will discolourise in presence of light and or heat, as well as it often will be found that radiation sterilisation process will lead to a dissatisfactory change of colour of the composition in which it is comprised whether it is in a cream or a gel or a medical device. Moreover, such antibacterial compositions are often intended for use for medical or cosmetic purposes under which circumstances a discoloration is very unfortunate and potentially prevents the use of silver ions for said use.
None of the above references describe examples of hydrophilic polymer formulations or devices comprising such formulations containing silver compounds for use as antiseptic being stable against discoloration due to reduction of the silver ion or being stable against potential convertion of the silver ion into the dark stained compounds of silver such as metallic silver or the silver sulphide.
It is an object of the present invention to provide complex structure rendering silver ions stable against loss of the antiseptic activity and against darkening due to reduction of the silver ions or the formation of darkly stained sparingly or insoluble silver compounds.
Further it is an object of the invention to provide principles and methods of introducing the silver compositions stabilised against the effect of light into catheters guide-wires or similar medical devices or instruments.
It has now surprisingly been found that silver ions may effectively be stabilised against exposure to light by formation of simple complexes with primary, secondary or tertiary amines which complexes are associated to hydrophilic polymers.
BRIEF DESCRIPTION OF THE INVENTION
The present invention relates to stabilised compositions having antibacterial, antiviral and/or antifungal activity.
Furthermore, the invention relates to a method of producing compositions having antibacterial, antiviral and/or antifungal activity.
Still further, the invention relates to medical devices having a coating comprising compositions having antibacterial, antiviral and/or antifungal activity.
The invention also relates to the use of the stabilised compositions having antibacterial, antiviral and/or antifungal activity for producing a wound dressing or an ostomy appliance, an incontinence device, other medical devices or hydophilic coatings.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a stabilised composition having antibacterial, ariniviral and/or antifungal activity which composition is characterised in that it comprises a silver compound in the form of a complex with a primary, secondary or tertiary amine which complex is associated to one or more hydrophilic polymers.
The amine being used in the compositions of the invention are suitably a primary, secondary or tertiary lower alkyl amine or amino alcohol having a free lone pair of electrons.
A lower alkyl amine is preferably selected from mono, di or tri methyl, ethyl, propyl or butyl amines or mixtures thereof.
A lower alkyl amino alcohol is preferably selected from mono, di or tri methyl ethyl or propyl aminoalcohols or mixtures thereof.
The compositions of the present invention will show alkaline properties in aqueous solutions and the pH may be adjusted to a value from 6.5 to 8.5 or/or neutralised using an appropriate acid such as a mineral acid such as hydrochloric acid.
Without restricting the invention to any specific theory, it is believed that the stabilisation of the silver compound is to be ascribed to a formation of a complex between the silv
Larsen Kim Lambertsen
Pedersen Lars Haastrup
Samuelsen Peter Boman
Coloplast A/S
Fubara Blessing
Jacobson & Holman PLLC
LandOfFree
Stabilized compositions having antibacterial activity does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Stabilized compositions having antibacterial activity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stabilized compositions having antibacterial activity will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2940119