Re: Change of Existing Medical Devices and 510(k) - "Letter to File" and "Add to File
I started working in regulatory a few years before the FDA changed to the new
510k paradigm and the format of Traditional, Special and Abbreviated 510k.
From my experience, "Add-To-File" was a previous version of "Special 510k". Before when you had a major change to a current product 510k, you would submit the changes to the FDA under "Add-To-File" which meant "Add To the current 510k File". Now you submit the changes under "Special 510k".
The definition of "Letter-To-File" has never changed. This is a simple 1-3 page brief summary on why you think you don't need a 510k submission. Attached to this is a copy of the R&D/Engineering notes on the change. The memo briefly explains the change, whether biocompatibility testing was/was not done and why per ISO 10993-1, how the change does not effect safety and efficacy, and a summary of data to support your explainations. I always attach a copy of the FDA flow charts from the guidance on "Deciding When to Submit a 510(k) for a Change to an Existing Device" with my notes on all relevant parts of the flow chart that apply.
Now if the change is minor enough, you don't even do a "Letter-To-File". Just record the design change data in the device design records. The hardest part sometimes is defining consistently in a company what does and does not require a "Letter-To-File". It depends a lot on the risk and classification of a product. My rule of thumb is if I have to use the FDA flow chart, at a minimum I write a "Letter-To-File".
So far every company I have worked for has roughly followed this pattern. I was originally trained on how to do 510k's from a manager that was submitting docs to the FDA since the early 1980's when a 510k was just 3-4 pages long. Man has that changed!!
Does anyone else have a different experience?