One of the most prominent technical trends. of the industry has been the continued Increase in the proportion of engineered ptoducts coming to the market. The vast majority, of biopharmaceuticals approved during the 1980s and early 1990s were either first generation murine monoclonals or unmodified replacement proteins [e.g., human growth hormone (hGH), interferons, blood factor VIII, and erythropoietins-all identical in amino acid sequence to the native human protein and, administered In order to replace or augment. natural levels of that protein]. This article focuses on more recent approvals and trends in engineering,approaches for biopharmaceutical production.