MF63 is primarily used in the development of influenza vaccines. It acts as an adjuvant, enhancing the body's immune response to the vaccine. This makes the vaccine more effective, especially in populations with weaker immune systems, such as the elderly. By boosting immunity, MF63 helps improve the overall efficacy of influenza vaccines, providing better protection against seasonal flu strains. Its application is crucial in advancing vaccine technology and public health efforts to combat influenza.