Multi-block segmented copolymers of biodegradable separate phases and release of biologically active polypeptides

摘要

A composition for the controlled release of at least one biologically active polypeptide having a molecular weight of less than 10,000 in the host, comprising at least one biologically active polypeptide encapsulated in a matrix comprising at least one biodegradable, thermoplastic and multiblock copolymer of separated phases, where the copolymer is characterized in that: (i) it comprises at least two hydrolysable segments selected from a prepolymer (A) and a prepolymer (B), the prepolymer (A) has a Tg less than 37 ° C and the prepolymer ( B) has a Tm of 40 ° C - 100 ° C in conditions of the human body; (ii) the separated phase copolymer has at least two phase transitions, each of which is related to the corresponding Tg or Tm values of the prepolymers that are comprised in the copolymer; (iii) the prepolymer (A) comprises reaction products of cyclic monomers selected from glycolide, lactide, ε-caprolactone, δ-valerolactone, trimethylene carbonate, tetramethylenecarbonate, 1,5-dioxepan-2-one, 1,4-dioxan- 2-one (para-dioxanone) and / or cyclic anhydrides such as oxepan-2,7-dione; and wherein the prepolymer (A) contains a segment that is derived from a water soluble polymer, preferably wherein said water soluble polymer is derived from a diol, diamine or diacid; (iv) a prepolymer (B) comprising poly (ε-caprolactone) with an Mn of more than 3000; (v) segments that are linked by a diisocyanate chain extender; (vi) the segments are randomly distributed along the polymer chain; and (vii) said copolymer contains poly (ethylene glycol), as a segment of the prepolymer (A) and / or as an additional prepolymer, and wherein said poly (ethylene glycol) a) has a molecular weight of 200 to 3000 g / mol, and b ) is present in an amount of 5% by weight to 60% by weight.