Composition with sustained release of active principle, capable of forming a microemulsion

Composition intended to be ingested, comprising a system which is self-microemulsifying on contact with a hydrophilic phase provided, after ingestion, by physiological fluid, the said self-microemulsifying system comprising:

• at least one active agent;
• a lipophilic phase consisting of a mixture of mono-, di- and triglycerides and of C8-C10 fatty acids and of polyethylene glycol monoesters and diesters with a hydrophilic/lipophilic balance (HLB) of less than 16;
• a glyceride-based surfactant (SA) with an HLB of less than 16, selected from the group consisting of saturated C8-C10 polyglycosylated glycerides and oleic esters of polyglycerol;
• a co-surfactant (CoSA) selected from the group consisting of fatty acid esters of propylene glycol, oleic esters of polyglycerol, and ethyl diglycol;
• an inert polymer matrix, representing from 0.5% to 40% relative to the weight of the total composition, which is not ionizable at physiological pH, dispersed in the self-microemulsifying system before ingestion, the said polymer matrix being capable, after ingestion, of forming, in contact with physiological fluid, a gelled polymer matrix making it possible to release the thus microemulsified active agent in a continuous and sustained manner by diffusion, and wherein the surfactant—co-surfactant ratio is between 0.5 and 6.