OROS technology as an engineering approach to controlled drug release (review)

Introduction. The development of oral dosage forms with controlled release remains an important area of modern pharmaceutical technology. Such systems can reduce fluctuations in plasma drug concentration, decrease dosing frequency, and improve the convenience of long-term therapy. Among modified-release platforms, osmotic drug delivery systems are of particular interest because the release of an active pharmaceutical ingredient is governed not only by its physicochemical properties but also by predefined engineering parameters of the dosage form. These parameters include the core composition, osmotic gradient, semipermeable membrane properties, the presence and size of the delivery orifice, and the characteristics of the push layer, etc.

Text. This review aims to analyze OROS technology as an engineering platform for controlled drug release, with consideration of the main structural types of osmotic systems, their mechanisms of action, critical formulation factors, and technological limitations.

Conclusion. The analysis of literature and patent data shows that OROS remains a relevant approach to the development of modified-release dosage forms owing to its ability to provide programmable and reproducible drug release. The elementary osmotic pump, push-pull osmotic pump and controlled-porosity osmotic pump are of the greatest practical importance, as these systems address different technological tasks: delivery of soluble drugs, release of poorly soluble active pharmaceutical ingredients, and formation of a microporous release pathway without a separate laser-drilling step. At the same time, OROS systems require careful pharmaceutical design, control of critical quality attributes, and specialized manufacturing equipment. These factors limit their widespread implementation but maintain strong interest in this technology for the development of modern prolonged-release oral drug products.

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