Pharmaceutical compositions comprising dextran with a molecular weight of 1.0-100 KDA and processes for their preparation
A solid or semisolid implant obtainable by providing a liquid composition comprising an aqueous solution of dextran with molecular weight of 1.0-100 kDa and introducing the liquid composition into the body of a mammal, whereby the implant is formed in situ in the body of the mammal. A process for preparing a composition useful for biomedical application, comprising the steps of providing a liquid composition comprising an aqueous solution of dextran having a molecular weight of 1-100 kDa; and bringing the liquid composition to solidify; whereby water is gradually eliminated from the liquid composition during the solidification. A biomedical article prepared from the composition.
1. A process for preparing a composition, said composition being suitable for the controlled release of a biologically active protein in the body of a mammal, said process comprising:
(a) providing an aqueous solution of dextran having a molecular weight of 1-100 kDa at a concentration within the range of 25-75% by weight;
(b) introducing a biologically active protein into the aqueous solution of (a) to form a liquid composition; and
(c) forming a solid matrix from said dextran in said liquid composition by bringing said dextran in said liquid composition to a solid form by gradually eliminating water from said liquid composition by evaporation or extraction, thereby providing a composition in which said biologically active protein is contained within said solid matrix.
2. The process of claim 1 , wherein the molecular weight of dextran is 1-70 kDa.
3. The process of claim 1 , wherein dextran is present in said aqueous solution of (a) at a concentration within the range of 50-75% by weight.
4. The process of claim 1 , wherein water is eliminated from said liquid composition by evaporation.
5. The process of claim 4 , wherein said evaporation is performed at temperature of from 0° C. to 500° C.
6. The process of claim 5 , wherein said evaporation is performed at temperature of from 20° C. to 370° C.
7. The process of claim 4 , wherein the rate of evaporation is 0.1-75% by weight of said liquid composition per hour.
8. The process of claim 1 , wherein water is eliminated from said liquid composition by extraction.
9. The process of claim 8 , wherein said extraction is performed by adding 1-10 parts by weight of ethanol, liquid polyethylene glycol (PEG), or liquid polypropylene glycol (PPG), to 1 part by weight of said liquid composition.
10. The process of claim 1 , wherein said biologically active protein is dissolved or suspended in said aqueous solution.
11. The process of claim 1 , wherein said biologically active protein is introduced in an amount so as to be present at a concentration of 0.01 to 25% by weight in said liquid composition.
12. The process of claim 1 , wherein said protein is insulin.
13. An article for biomedical applications comprising a composition prepared by the process of claim 1 .
14. The article of claim 13 , wherein said article is in the form of a hard pharmaceutical capsule.
15. The article of claim 13 , wherein said protein is insulin.
16. The article of claim 13 , wherein said protein is insulin and said article is in the form of a hard pharmaceutical capsule.