Introduction: Controlled release (CR) dosage forms comprise a wide range of technologies, which modify the drug pharmacokinetic (PK) profile by avoiding the immediate release (IR) of the active pharmaceutical ingredient (API). They are particularly of interest in chronic diseases, for narrow therapeutic index drugs or for targeting a particular gastrointestinal tract (GI) segment.Areas covered: Diffusion and dissolution limited controlled release systems are described in terms of release kinetics and formulation strategies with e xamples marketed or under development. Additionally, the physiological variables affecting the release (such as fluid pH, volume and composition, physical forces, and transit times) and the in vitro dissolution techniques currently available are reviewed.Expert opinion: Selection of the appropriate release mechanism is not a straightforward process, as it requires a balance based on the desired target, the API properties and the technological challenges of the dosage form structure. Diffusion, dissolution or a combination of both could be adequate without an absolute superiority of one mechanism over the other. The combination of in vivo predictive dissolution systems, with mathematical modeling of the release mechanism and its correlation with formulation composition could help to design prototype candidates, with enhanced probabilities of success in human clinical trials.

中文翻译：

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口服控释剂型：溶出与扩散。

简介：控释（CR）剂型包含多种技术，它们通过避免活性药物成分（API）的立即释放（IR）来改变药物的药代动力学（PK）特性。它们特别适用于慢性疾病，狭窄治疗指标的药物或靶向特定胃肠道（GI）的领域。涵盖的领域：扩散和溶出受限控释系统以释放动力学和配方策略描述，市场上有售或正在开发中。此外，还对影响释放的生理变量（例如液体pH，体积和组成，物理力和运输时间）以及目前可用的体外溶出技术进行了综述。选择合适的释放机制并不是一个简单的过程，因为它需要基于所需目标，API特性和剂型结构的技术挑战之间取得平衡。扩散，溶解或两者结合可能就足够了，而没有一种机制比另一种机制具有绝对优势。体内预测溶出度系统与释放机理的数学模型及其与制剂组成的关系的组合可以帮助设计原型候选物，从而提高人类临床试验成功的可能性。如果没有一种机制相对于另一种机制的绝对优势，那么溶解或两者结合可能就足够了。体内预测溶出度系统与释放机理的数学模型及其与制剂组成的关系的组合可以帮助设计原型候选物，从而提高人类临床试验成功的可能性。如果没有一种机制相对于另一种机制的绝对优势，那么溶解或两者结合可能就足够了。体内预测溶出度系统与释放机理的数学模型及其与制剂组成的关系的组合可以帮助设计原型候选物，从而提高人类临床试验成功的可能性。