Biopharmaceutical based medicines are typically proteins, peptisides or genomic materials which are produced from living organisms, ussually in fermenters or bioreactor. They account for an increasing proportion of the world pharmaceutical markets and in 1996 made up US$ 10.7b (8.3%) of drug sales in the US. There are 284 new biotechnlogy drugs in trials in the US and it is estimated that by 2000, 85% of all new pharmaceuticals will result from biotechnological processes and R&D. Several of the earliest patents to protein drugs ( human growth hormone and insulin ) are now expiring and it is predicted that generic versions of key biotech products will be marketed by 2000 and could together earn US$2.6b pa in thier first three years.