Modern pharmaceutical manufacturing techniques frequently rely upon biotechnology.

Amongst the earliest uses of biotechnology in pharmaceutical manufacturing is the use of recombinant DNA technology to modify Escherichia coli bacteria to produce human insulin, which was performed at Genentech in 1978. Prior to the development of this technique, insulin was extracted from the pancreas glands of cattle, pigs, and other farm animals. While generally efficacious in the treatment of diabetes, animal-derived insulin is not indistinguishable from human insulin, and may therefore produce allergic reactions. Genentech researchers produced artificial genes for each of the two protein chains that comprise the insulin molecule. The artificial genes were "then inserted... into plasmids... among a group of genes that" are activated by lactose. Thus, the insulin producing genes were also activated by lactose. The recombinant plasmids were inserted into Escherichia coli bacteria, which were "induced to produce 100,000 molecules of either chain A or chain B human insulin." The two protein chains were then combined to produce insulin molecules.

Escherichia coli bacteria, which are often utilized in production of pharmaceutical products.

Insulin crystals

Growth hormone

Transgenic Farm Animals

A pig, transgenic generations of which might be used to produce blood substitutes for use in humans.

Recombinant DNA techniques have also been employed to create transgenic farm animals that can produce pharmaceutical products for use in humans. For instance, pigs that produce human hemoglobin have been created. While blood from such pigs could not be employed directly for transfusion to humans, the hemoglobin could be refined and employed to manufacture a blood substitute