FDA has revised its position on 510(k) submissions for peripheral vascular atherectomy devices in light of feedback from Cook Medical, sharing its final guidance this week.
The guidance features multiple small changes to the 2018 draft such as the removal of a recommendation to compare “measurement tolerances” of the predicate and investigational devices.
Finalization of the guidance gives developers of peripheral vascular atherectomy devices a resource to draw on when preparing to submit products for 510(k) clearance.
Atherectomy is an interventional procedure to remove plaque from diseased arteries. Many of the core concepts presented in the 2018 draft guidance survived the consultation and finalization process. For example, FDA still divides atherectomy devices up into four categories — directional, rotational, orbital and laser — based on the mechanism through which they remove plaque.
However, FDA has also made changes throughout the text, some of which reflect feedback from Cook Medical. It was the only company to publicly comment on the draft, although Boston Scientific, Medtronic, Philips and Cardiovascular Systems all make devices used in atherectomy procedures.
Issues raised by Cook included the inclusion of “measurement tolerances” in a predicate device comparison table. The company argued “one cannot know device tolerances, typically applied to manufacturing specifications, of a competitive predicate, nor would FDA traditionally expect to see this characteristic as a substantial equivalence determination feature.”
Following Cook’s recommendation, FDA replaced “measurement tolerances” with “dimensional characteristics,” a term that covers attributes such as the length and French size of the device. The company successfully argued the term is “more appropriate.”
FDA also changed a section on assessing corrosion resistance. The final guidance features a section proposed by Cook Medical that describes how visible signs of corrosion can negatively impact performance characteristics, even if they do not lead to toxicity or embolization.
While those changes and some other tweaks reflect feedback from Cook Medical, there are no public comments related to other revisions to the draft. For example, FDA has completely removed a section outlining the need to evaluate the robustness of catheter tips. In the draft, FDA stated such evaluations are important because a fault with the distal tip could damage blood vessels.
Other significant changes include the expansion and relocation of a section on automated handling functionality. The section applies to devices that are controlled using directional buttons, rather than being physically maneuvered by hand. In finalizing the guidance, FDA expanded its description of automated handles and maintained its position that they should be evaluated in bench and animal tests.