Smart closed-loop drug delivery systems.

The administration of therapeutics for long-term chronic disease management or treatment faces considerable challenges, such as the need for precise dosage control, timely delivery and adherence to medication regimens. Traditional drug delivery methods often result in suboptimal therapeutic outcomes owing to variable responses, fluctuating drug concentrations and lack of feedback from real-time monitoring. Smart closed-loop systems (CLSs) could address these limitations by integrating real-time biosensing with automated drug delivery, thereby personalizing treatments to individual needs. This Review explores the current landscape of CLSs, highlighting recent advancements in wearable and implantable technologies that facilitate continuous monitoring of biomarkers and offer responsive therapeutic interventions. We discuss the implications of device design and the trade-offs between wearable and implantable systems. In addition, we highlight the potential of artificial intelligence enhancement of CLS control algorithms by enabling systems to learn from and predict responses to achieve more effective and adaptive optimal therapies. Ultimately, this Review charts a path towards next-generation CLSs, emphasizing the integration of synthetic biology and engineered cells into implantable devices.