Biotechnology allows for a mass production of proteins. For example, hormones (used for the growth) was previously found by extracting the sample from cadavers. Insulin (used to help control diabetes) was previously extracted from the pancreas of many slaughtered animals, including cattle and pigs. tPA (proteins acting as enzymes to dissolve blood cells) are produced by biotechnology. This protein treats heart attack victims by dissolving blood clots that are blocking the flow of blood.
Vaccinations (making people immune to an infectious organism) are also produced by biotechnology. Bacteria and viruses have surface proteins, and a gene for just 1 of these can be used to genetically used to engineer bacteria. Copies of the surface proteins can be used as vaccines. Not only are more vaccines produced, but it takes much less for the surface proteins to be created to, in turn, create the vaccine.
At this time, vaccinations for Hepatitis B are made and already used in fields of medicine today. Right now, scientists are experimenting what can be used for vaccinations for AIDS, malaria, and many other "incurable" diseases. This is how biotechnology is used in science and in medicine today.
2.) Company that produces proteins for pharmaceutical use found in the milk of transgenic animals (How does this benefit the human medical field?)
3.) Treatments (in experiment) used for cancer and other disorders