Particulate constructs for release of active agents

A composition comprising particles obtained from fast mixing according to the Nano Precipitation process

• a) an amphiphilic stabilizer,
• b) a conjugate of the formula
• (active−linker)n−hydrophobic moiety (1)
• wherein n is an integer of 1-100;
• “active” refers to a first therapeutic agent;
• “linker” is a divalent residue of an organic molecule which comprises a bond that is selectively cleavable by reduction or hydrolysis to control the rate of release of said active from the particles free of said hydrophobic moiety or portion thereof;
• and
• “hydrophobic moiety” refers to the residue of an organic molecule that is insoluble in aqueous solution;
• and
• c) a second therapeutic agent different from the first therapeutic agent to obtain said particles,
• and wherein the hydrophobic moiety is a polymer having a molecular weight between 800 and 200,000 g/mole or is a natural product, and the amphiphilic stabilizer is a copolymer having a hydrophilic region and a hydrophobic region wherein said copolymer is a graft, block or random amphiphilic copolymer and has a molecular weight between 1,000 g/mole and 50,000 g/mole.