Background <p>Application of peptide drugs is a promising pharmaceutical category, attributed to their great specificity to targets, activity in biology and safety. Biomolecules of this class are of therapeutic interest in a wide variety of disease state (such as metabolic diseases, cancer, cardiovascular diseases and infectious diseases).</p> Challenges <p>However, the application of peptide drugs in the clinic is strongly hampered by the formulation and delivery problems, like enzymatic degradation, limited membrane permeability, rapid urinary excretion, short or too short systemic half-life for the maintenance of therapeutic concentrations, low bioavailability, and efficacy.</p> Formulation and Delivery Strategies <p>To avoid or ameliorate these restrictions, the following strategies have been the subject of many researches, includes development of novel delivery systems using the processes like PEGylation, glycosylation and nanocarrier encapsulation, but also, investigation of alternative and non-invasive administration routes, such as oral, nasal or cutaneous application.</p> Analytical Characterization <p>The successful development of peptide formulations hinges on robust characterization and quality control methodologies. Techniques such as nuclear magnetic resonance (NMR), CircularDichroism (CD),liquid chromatography–mass spectrometry (LC–MS), Fourier-transform infrared (FTIR) spectroscopy, and Size-Exclusion Chromatography (SEC), including advanced techniques (hydrogen–deuterium exchange mass spectrometry (HDX-MS), andsmall-angle X-ray scattering (SAXS), Analytical Ultracentrifugation (AUC), Surface Plasmon Resonance (SPR) etc.) are critical forconfirming structural fidelity, conformational stability, and impurity profiles. The incorporation of artificial intelligence–assisted dataanalysis further refines data analysis by improving spectral interpretation and pattern recognition.</p> Future Perspectives <p>Effective bench to clinic peptide therapeutics translations involve the combination of an ensemble view of new formulation strategies and well-developed multidimensional characterization methodologies. The introduction of the technologies of data analysis, along with AI-controlled data processing, are likely to be a significant factor contributing to the enhancement of the design of formulations, quality control, and regulatory compliance. The purpose of this review is to fill the gap between formulation science and analytical characterization, to give a summary reference to inform the design of upcoming peptide-based drug products.</p> Graphical Abstract <p></p>