My previous company was involved in this. Due to new technology our product was classified as Class III. We used the De Novo approach, and eventually had it downgraded to a class II with special controls.
From the FDA webpage:
The Center for Devices and Radiological Health is currently working on a new draft de novo guidance, that when finalized, will represent the FDA’s current thinking on this topic. Until the new draft de novo guidance is published, please contact 510(k) Staff at 301-796-5640 for information regarding the de novo process.
You should expect that it is not easy to have a product downclassified. It will take very good documentation, a lot of interaction with the CDRH, and quite a bit of resources. However, it is possible - depending on the product, the technology involved, and the risk of the product.
