How do large molecule drugs differ from small molecule drugs?

Large molecule drugs primarily differ from small molecule drugs in that they are usually protein-based and are developed through biological systems, such as living cells. These drugs, often referred to as biologics, include monoclonal antibodies, therapeutic proteins, and vaccines, which are typically much larger and more complex in structure compared to small molecule drugs.

Biologics are produced using biotechnology methods, which involve genetically engineered organisms that can replicate the necessary proteins. Because these large molecules are derived from natural sources, they often exhibit higher specificity and can target specific pathways or cells in the body, which is a significant advantage in therapeutic applications.

In contrast, small molecule drugs are typically chemically synthesized, have lower molecular weights, and can easily penetrate cell membranes due to their size. This distinction is crucial for understanding the differences in the mechanism and development of these two categories of drugs, affecting their distribution, metabolism, and excretion within the body.