Immuno-stimulators are chemical compounds that can be drugs or nutrient substitutes that induce resistance in the human body by encouraging stimulation or increasing activity of any of its mechanisms. Immune-stimulants are broadly classified into specific immune-stimulants and non-specific immune stimulants. Specific immune-stimulants deliver antigenic specificity in immune response, while non-specific immune-stimulants act without considering the antigenic specificity. Immune check activators are induced to enhance the activity of an immune systems over the antigen. There are no specific approved immune check activators available in the market, with over 20 molecules under clinical trials.