Abstract
U.S. Food and Drug Administration (FDA) approval of Class III medical devices can take from 3 to 7 years. Although this is shorter than times for drug approvals, patients with serious or life-threatening diseases and disorders may not have time to wait for device approval to access needed treatments. The FDA has a number of pathways, similar to drug approval processes, for expanded use of unapproved medical devices in patients for whom no reasonable alternative therapy is available. Additionally, the FDA regulates the manufacture and use of "custom" medical devices-those made for use by 1 specific patient. With the advent of 3-dimensional printing and bioprinting, new rules are evolving to address concerns that lines may be blurred between "custom" treatments and unregulated human experimentation.