Development and validation of a seizure initiated drug delivery system for the treatment of epilepsy

Abstract Delivery of small dosages of anti-epileptic drug (AED) directly into the brain from implantable degradable polymers has been reported to alleviate epilepsy activity in a GAERS animal model, however this system delivers a continuous dose of AED to the brain. We describe here the development of an active drug delivery system whereby AED delivery is initiated by the onset of an epileptic event and controlled by a custom hardware device. The system is comprised of an electrocortigographic (ECoG) data receiver, computational hardware, and a drug delivery component. The system initiates the release of an AED from an electrically conductive polymer when a seizure biomarker is detected above a pre-set threshold. Evaluation of the system showed that it is possible to vary the quantity of drug released linearly by varing the amount of charge injected into the drug loaded electroactive polymer. In addition it is possible to induce drug release within 10 s of injecting the charge, highlighting the responsive nature of the system. This work demonstrates a significant advance in the development of a device that combines the electronics capable of monitoring ECoG activity, detecting epileptic seizures and initiating drug delivery.

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