Medical devices include a range of technologies, from surgical gloves, syringes, and thermometers to sophisticated prosthetics, imaging equipment, artificial heart valves, and electronic neurostimulators. Reflecting this diversity, the path from idea to product development for medical devices can be quite variable and quite different from that for drugs and biologics. The same is true for the extent of collaboration among academic, industry, and government researchers. Before they can market complex devices, device manufacturers must seek either premarket clearance (which is most common and which generally does not require clinical data) or premarket approval (which is required for only a small number of devices—often implanted devices—and which does require clinical data) from the FDA. As is the case for drugs, obtaining premarket approval is a complicated process that can take many years. For complex medical devices, the research team may include physicists, materials scientists, engineers, and mathematicians, as well as biologists and physiologists. Physicians often play a critical role in defining the needs for devices and the initial testing of prototypes in human clinical trials. In some cases, the basic idea for important medical devices can come from individuals who are not involved in basic or clinical research. For example, the idea (and crude first model) for a device to drain the buildup of cerebrospinal fluid in individuals with hydrocephalus came from a self-described mechanic who was the parent of an affected infant (Baru et al., 2001).
The following sections briefly describe the sequence of events for small-molecule drugs from concept to a marketed product. Figure E-1 (developed by the authors) depicts the process in graphic form for each of the following seven sections. (A more thorough review of the research and development process for small molecules, therapeutic proteins, vaccines, medical devices, and diagnostics can be found at www.rdguide.org.)
Long before a new drug can even be imagined, scientists are working to gain a basic understanding of a disease or of specific normal chemical pathways that are subverted in an abnormal cell. This research might be conducted in academic laboratories and research institutes around the world, and some of it is paid for by industry. Industry also plays a large role in the development of novel technologies, such as new approaches to sequencing of the human genome.
Along the road toward developing new medications, researchers have to acquire a basic understanding of bacterial, animal, and human genomes. They study which genes are involved in specific diseases. They also look at how gene products—or proteins—contribute to the derailments in cellular processes that result in the initiation or maintenance of a disease.