Biomarkers are molecules or parameters that provide critical information about the efficacy of treatments. Essentially, they help follow up on the patient's condition at each stage of the disease. For example, we can detect signs of upcoming disease based on a certain amount of protein in the blood of very high-risk individuals. Biomarkers can be useful in evaluating newly developed drug responses since most molecular-based treatments change specific pathways inside cells. One of the most significant advantages of novel biomarkers is the reduction of clinical trial failures. Biomarkers are used in research to design and create more effective therapies, to assist in identifying which candidates to pursue further, as surrogate markers for selecting patients, and as endpoints for both benefits and hazards. A wide range of biomarkers, such as predictive, prognostic, pharmacodynamic, safety, and efficacy markers, can be monitored. Interestingly, novel biomarkers like proteins, mRNA, and microRNAs can function as routine physiological parameters like blood pressure or body temperature. The molecular biomarkers can be discovered in serum, plasma, and other body fluids or expressed in specific cells or tissues. Exosome-encapsulated molecules that protect against digesting enzymes, resulting in greater stability, are the next generation of molecular biomarkers. Biomarker validation involves measuring their levels in response to a disease, condition, or another parameter that must be statistically significant and recurring. This collection aims to demonstrate standardized protocols for introducing and validating new biomarkers, provide broader access to existing methods, and help researchers interested in working in this field.