Marketing approval for the lithotripter.

In December 1984, the Food and Drug Administration (FDA) granted Dornier Systems (FRG) approval to market the external shock wave lithotripter (ESWL) in the USA. The Medical Device Amendments of the Food, Drug, and Cosmetic Act require that the FDA evaluate the safety and effectiveness of medical devices intended for commercial distribution in the U.S. Such evaluation includes basic scientific studies, animal testing, and investigational studies in human subjects, culminating in a judgment concerning acceptable risks in terms of anticipated benefits, and whether the device is effective for its intended use. Prior to human studies in West Germany, Dornier had evaluated the destruction of stones of varying composition, measured the rate and energy of stone destruction, and tested blood samples and lymphocyte cultures exposed to shock waves. In addition, studies in both rats and dogs had demonstrated the feasibility of the technique and evidence of safety. Such data are provided by manufacturers when applying for an investigational device exemption (IDE) from the FDA, which permits clinical studies in humans; such studies also require the approval of an Institutional Review Board. The FDA approved Dornier's IDE, allowing human investigational use of the ESWL in facilities in the U.S., conducted concurrently with similar studies in West Germany. Upon completion of clinical trials, data acquired in vitro, in laboratory animals, and in human investigations are submitted to the FDA for a premarked approval application (PMAA). The Agency was given 6 months to make a decision, taking into consideration the recommendation of an advisory panel of experts from outside the Agency who had reviewed the same data. In its evaluation of the ESWL for safety and effectiveness, the FDA considered the question of alternative practices and procedures to treat nephrolithiasis, including percutaneous nephrolithotomy and open surgical procedures, and the adverse effects of such procedures. Clinical data available at the time of review for approval included reports of treatment of 667 patients in West German centers, and 327 patients treated in three U.S. facilities. Dornier and the FDA initiated discussions concerning the labeling of the device and a postmarketing surveillance plan. These were completed and marketing approval for the ESWL was granted.