Patent ID: 8236353

Claim:
A liquid pharmaceutical formulation for the sustained release of at least one active principle (AP), said pharmaceutical formulation comprising at least one active principle (AP) and an aqueous suspension based on colloidal particles of a polymer (PO), or a pharmaceutically acceptable salt thereof, which satisfies the following four conditions: (a) the polymer (PO) has the following formula (I): in which: i) A independently is an —NHR group in which R represents H; a linear C 2 to C 10 or branched C 3 to C 10 alkyl or benzyl; a terminal amino acid residue or a terminal amino acid derivative of formula: in which: R 7 is selected from: OH, OR 9 wherein R 9 is a linear C 2 to C 10 or branched C 3 to C 10 alkyl or a benzyl or NHR 10 wherein R 10 is an H, a linear C 2 to C 10 alkyl, a branched C 3 to C 10 alkyl or a benzyl; R 8 is selected from an H, a linear C 2 to C 10 alkyl, a branched C 3 to C 10 alkyl or a benzyl; ii) B is direct bond or a divalent, trivalent or tetravalent bonding group; iii) D is selected from the group consisting of: H, a linear C 2 to C 10 acyl group, a branched C 3 to C 10 acyl group or a pyroglutamate; iv) the hydrophobic groups GH each are, independently of one another, a group chosen from: linear or branched C 8 to C 30 alkyls; C 8 to C 30 alkylaryls or arylalkyls; C 8 to C 30 (poly)cyclic compounds; v) R 70 is a cationic group (CG) chosen from the group consisting of: —NH—(CH 2 ) w —NH 3 + in which w is between 2 to 6 and, —NH—(CH 2 ) 4 —NH—C(═NH)—NH 3 + , —O—(CH 2 ) 2 —NH 2 + , —O—(CH 2 ) 2 —N+(CH 2 ) 3 , a group having the following formula: in which —R 11 is selected from the group consisting of —H, —CO 2 H, an alkyl ester, —C(═O)—NH 2 , —C(═O)—NH—CH 3 or —C(═O)—N(CH 3 ) 2 ; an amino acid residue or an amino acid derivative of formula: in which: X is —O or —NH—, R 12 is selected from the group consisting of: H, a linear C 2 to C 10 or branched C 3 to C 10 alkyl or a benzyl, R 13 is —(CH 2 ) 4 —NH 3 + , —(CH 2 ) 3 NH—C(═NH)—NH 3 + , —(CH 2 ) 3 NH 3 + ; vi) the counteranion of R 70 is an expedient group; vii) R 90 is a hydroxyethylamino-, a hydroxyalkyloxy or a polyoxyalkylene; viii) p, q, r and s are positive integers; ix) (p)/(p+q+r+s) is defined as the molar degree of grafting of the hydrophobic groups GH and varies from 2 to 30 molar %, provided that each copolymer chain has, on average, at least three hydrophobic grafts; x) (q)/(p+q+r+s) is defined as the molar degree of grafting of the cationic groups and varies from 10 to 98 molar %; xi) (p+q+r+s) varies from 50 to 300; xii) (r)/(p+q+r+s) varies from 0 to 78 molar %; and xiii) (s)/(p+q+r+s) varies from 0 to 55 molar % (b) the pHf value of the pH of said formulation is between 3.0 and 6.5; (c) at the pHf value, the polymer (PO) forms a colloidal solution which associates spontaneously and noncovalently with the active principle (AP); and (d) said formulation exhibits a precipitation factor PF of greater than 200.