Ann: DurAVR first successful implantation Valve-in-Valve, page-20

I don't want to belabor the point but I do think there can be somewhat of an evidence-based approach to gauging our chance of getting a Humanitarian Device Exemption with the FDA.

The FDA's HDE guidelines specify that for a device to get the exemption there must be no comparable approved device and that a comparable device does not have to identical to the device in question. If an HDE request is submitted and the FDA finds that there is a comparable device, the FDA will issue a refusal to file letter, meaning that the submission for the HDA won't be considered. Here are the guidelines with the pertinent info on comparable devices located on page 10:

https://www.fda.gov/media/74307/download

According to this 2022 study using data from the US government's Agency for Healthcare Research and Quality, both the CoreValve and Sapien XT were approved for ViV in 2015 and, according to that database which represents about 58% of US hospitalizations, during the 2016-2018 period there were 3,724 ViV procedures using the two devices. The mean age for the patients was 79 years old. Many of these were very old patients. Here is the study:

https://eurointervention.pcronline.com/article/valve-in-valve-transcatheter-aortic-valve-implantation-versus-repeat-surgical-aortic-valve-replacement-in-patients-with-a-failed-aortic-bioprosthesis

So there have been many thousands of ViV procedures done over the years using approved devices on very old patients, which leaves little doubt in my mind that an HDE will be not be possible due to there being comparable devices already commercialized and widely used.

I could be wrong of course, I'm just a guy on the internet. I hope I am but I am an American who has many years of experience investing in clinical stage companies dealing with the FDA and I think I have a decent idea about how guidelines are applied. We shall see.

If we just do a few hundred procedures in Canada over the next few years, helping those patients would be fantastic and could potentially add maybe something like $5 million to the coffers depending on reimbursement, which would always be welcome.