Biopharmaceuticals are produced in living cells using biotechnological processes and molecular biology methods, whereas synthetic drugs are products of chemical processes. Eukaryotic cells are becoming useful platforms for recombinant protein production. Production of biopharmaceuticals from E. coli or mammalian cell lines is achieved by the introduction of a gene or cDNA coding for the protein of interest into a well-characterized strain of producer cells. With molecular tools of genomics and proteomics, mammalian cells and plants can be used for the production of life-saving therapeutics. Production of biopharmaceuticals with plants provides benefits of cost-effectiveness, mass production at rapid rate, posttranslational modifications, and a product that is free from harmful pathogen contamination. Biopharmaceuticals show high specificity and target only specific molecules, which reduces side effects associated with conventional small-molecule drugs. The application of biopharmaceuticals has facilitated the treatment of patients who poorly respond to traditional synthetic drugs. The production of biopharmaceuticals in plants—known as molecular farming—offers benefits such as scalability, speed, and improved safety compared with insect and mammalian cell expression systems.