Discovery of insulin and its laboratory oriented clinical trials, and subsequently transfer the laboratory technology on isolated and purified insulin from cattle system for direct clinical trial on human system was the first phase of successful application of therapeutic bio-molecules. Later, these successful laboratory trials boosted the traditional pharmaceutical companies for commercialisation of therapeutic biomolecules in the global market. Wide acceptability of therapeutic protein has given challenge for more quality production of biopharmaceutical through genetically tailored host cells from various living sources. Although it is difficult to trace the beginning of biopharmaceutical companies, but it is sure to say that the period between 1918 and 1939 was marked by two breakthroughs with the discovery of insulin and penicillin.