Classification, material types, and design approaches of long-acting and implantable drug delivery systems

Long-acting drug delivery system is a development in pharmaceutical technology to minimize the disadvantages of other routes of administration such as oral, transdermal, and injectable administration. The major advantage of this system is the ability to maintain the drug concentration in plasma between the therapeutic ranges after a single administration. Consequently, multiple administrations are no longer required. Long-acting delivery can be achieved through nanoparticles, long-acting depot, and implantable devices. Several aspects related to the long-acting and implantable delivery system are comprehensively discussed in this chapter, including classification and drug release mechanism from the systems, and materials and fabrication method that can be used to prepare them. Finally, the recent updates on implantable devices design are also presented in this chapter.