Controlled Delivery Systems of Protein and Peptide Therapeutics

Protein and peptide therapeutics have been widely investigated as effective therapeutic agents for the treatment of various diseases, including cancer, metabolic, and autoimmune disorders [1]. Their global market is dramatically growing with more than hundreds of approved biopharmaceuticals [1]. Protein and peptide therapeutics have several advantages such as higher affinity and specificity to target molecules with low toxicity than small-molecule chemical drugs [2]. However, the administered protein and peptide therapeutics are unstable and easily degraded in the body [2]. In addition, because many protein and peptide therapeutics have their own target molecules, it is an important task to deliver these therapeutics into specific target sites without lysosomal degradation [3]. To improve patients’ compliance, safe and effective drug delivery systems (DDSs) are strongly needed for conventional biopharmaceutics. DDS is the process or method of administering a therapeutic agent for a controlled therapeutic effect [3]. Optimized DDSs enable long-term therapy, reducing the dosage of drugs, elevating therapeutic concentration of drugs for a long time, and targeting the disease site with reduced side effect of drugs [4]. These DDSs improve existing limitations of conventional drugs and bring various advantages in medical and economic issues [3]. Many patents of major protein and peptide therapeutics are expired or will be expired soon [5]. Recently, with the progress of nanotechnology, materials can be engineered at an atomic scale, and more sophisticated systems can be developed responding to various medical needs. In this review, we describe recent advances in protein and peptide DDSs and discuss current and potential strategies to improve the therapeutic efficacy for the treatment of various diseases using the cutting-edge technologies.1