In March 2017, the House released a 215-page discussion drat of a bill that would substantially overhaul the FDA's approach to diagnostics, both LDTs and IVDs. See the bill online here.
On May 4, Turna Ray of Genomeweb published a detailed article described an FDA technical response (comment) on the legislation. As of a couple weeks ago, the word was that the Hill was still waiting for this FDA document to arrive. The subscription Genomeweb article is online here. The journal obtained, analyzed, but didn't post the FDA document.
According to Genomeweb, FDA would encourage higher positioning for its "precertification" program based on lab or manufacturer reporting/recording of analytical and clinical validity. FDA was concerned about some details of the bill such as the breadth of its grandfathering clause.
A March 2018 Genomeweb article captured Commissioner Gottlieb's remarks at the ACLA annual meeting, where he also noted he was favorable to a long time legislative overhaul which would specialize diagnostic regulations away from the general regulation of medical devices like implants.
FDA is well along in its plans to create an all-new soup to nuts digital health pre-certification program in 2018 (here), and the future diagnostic pre-certification program would be analogous but fitted for diagnostics. FDA first rolled out elaborate genetic test pre-certification or self-certification in germline test authorizations crafted for 23andMe several years ago.