Abstract: The invention provides an article comprising, a mesoporous silicate matrix, such as a particle, having one or more pores; and one or more releasable caps obstructing one or more of the pores. The articles are useful as delivery vehicles for encapsulated agents such as therapeutic agents, polynucleotides, polypeptides and the like.

Abstract: A composition for the sustained delivery of a drug comprising an amphiphilic diblock copolymer; a poorly water-soluble drug; a biodegradable polymer; and liquid poly(ethylene glycol) or functional derivatives thereof and a process for preparing the composition are disclosed. When administered into a particular body site, the composition forms an implant containing the drug and drug containing polymeric micelles, which are slowly released from the implant to maintain a constant drug concentration for an extended period of time.

Abstract: The present invention relates to a pharmaceutical composition of a biologically active agent and a block copolymer composed of a poly(ethylene oxide) forming hydrophilic segment and a poly(butyl (alkyl)acrylate-co-(alkyl)acrylic acid) that is capable of forming supramolecular assemblies or micelles under favourable conditions. The supramolecular assemblies or micelles formed from said polymers associate or dissociate reversibly upon changes in the environmental pH. The pharmaceutical compositions of the present invention contain hydrophobic drugs, cations or polycationic compounds, which can be delivered to the body by oral route or other routes of administration.