Critical appraisal of the recent US FDA approval for earlier DBS intervention.

In November 2015, Medtronic announced the US Food and Drug Administration (FDA) approval for the use of deep brain stimulation (DBS) therapy in people with Parkinson disease (PD) "of at least 4 years duration and with recent onset motor complications, or motor complications of longer-standing duration that are not adequately controlled with medication." The approval was based on data from the EARLYSTIM clinical trial, a randomized, prospective, multicenter, parallel-group clinical trial in Germany and France involving 251 patients with PD. While others have reviewed the application of DBS earlier in the disease course and the results from EARLYSTIM, we focus on the conceptual, scientific, clinical, ethical, and policy issues that arise regarding the recent FDA approval.