Generally you want the predicate as close as possible. However, in your hypothetical example, it probably would be acceptable to use the "A+B" predicate and simply set your case for why not having "B" doesn't negatively impact safety and effectiveness. In particular, this is a fine approach for a Q-sub - a path which I would recommend because there are exceptions to this.
The most obvious exception is general use devices - just because a resection loop may say "cutting of soft tissue including neurological, cardiology etc" doesn't mean you can necessarily use it as a predicate for a device intended solely for cutting neurological tissue. That depends on a lot of factors, and even after all these years I can't quite guess which way a "specific" request will go.
You propose a good approach and I'd encourage you to continue with it.
g-
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Ginger Glaser RAC
Chief Technology Officer
MN
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Original Message:
Sent: 27-Aug-2018 23:06
From: Anonymous Member
Subject: 510k predicate
This message was posted by a user wishing to remain anonymous
Hi,
I understand the 510(k) process, but would need confirmation from this group of experts that my approach is OK, since there seems to be no exact predicate for my future device.
Basically, the question is whether it is acceptable if the intended purpose of my device, is a subset of the intended purpose of the predicate? I do not see why it wouldn't be accepted by the FDA.
Let's imagine we are talking about reprocessing some reusable medical devices, and that there are already a lot of devices cleared to perform "function B", and a lot of devices cleared to perform sequentially "function A and then function B". My future device performs "function A" only. Is that acceptable if I chose, as a predicate, a device that does "function A and then function B" and in my 510(k) only claim that my device does "function A"?
I am planning to validate the choice of predicate with the FDA as part of a Q-sub, but I am trying to build some confidence that this is an acceptable / the best approach.
Thank you for your help!
F