Insight Molecular Diagnostics Inc. (IMDX) Earnings Call Transcript & Summary

Good morning, and welcome to the Insight Molecular Diagnostics virtual KOL event. [Operator Instructions]. As a reminder, this call is being recorded, and a replay will be made available on the website following the conclusion of the event. I'd now like to turn the call over to Josh Riggs, Chief Executive Officer at Insight Molecular Diagnostics. Please go ahead, Josh.

Thanks, Sarah, and welcome, everybody. We're going to just do one quick slide on forward-looking statements. Thank you. We can move forward. So last year, we did our first KOL call with Dr. Anthony Langone, Vanderbilt University, about how blood-based DNA tests have made it easier to manage kidney transplant patients. And now our test Graft Assure Dx is working its way through the FDA for exactly that indication. After we finish with kidney, our team is preparing to start work on a claims expansion into heart. Today, we are grateful to have transplant cardiologists, Dr. Max Liebo of Loyola University I want to talk about how these types of tests are used to manage heart transplant patients here in the U.S. Thank you, Dr. Liebo for joining and offering to share some of your time and expertise. Guiding us through the conversation will be our very own Dr. Nick Ioannou, our Vice President of Medical Affairs, to whom I will now turn the call over. Thank you.

Thank you, Josh. Well, Josh started by telling us what's happening a year ago with Dr. [indiscernible], who came and talked about kidney transplants. I want to start by telling you what was happening about 10 years ago, when I started talking to my fellow colleagues, transplant nephrologists, transplant cardiologists about these donor-derived cell DNA tests. Ultimately, most of them when I was in there talking to them about these tests, they were saying, these are great tests. Will we be able to do these here in our labs. The answer back then was no. But you know what? Now that answer is yes. So I want to walk you through -- I want to take about 5 minutes and maybe even less, then walk you through some milestones, probably like 7 dates, how heart transplant has evolved. It starts off back in 1967 when the first heart transplant was performed by a fellow South African colleagues, Dr. Christian Barnhart. After that, heart transplant became pretty common. Many heart were transplanted, but the problem is there was a lot of rejection due to the body's immune system protecting itself. It would see a far in heart and he would say, this is not part of me, I have to reject it. In 1993, things changed because net the FDA-approved cyclosporin. And that drug works by suppressing the body's immune system. This led to an increase in heart transplantation rates. The health of the newly transplanted hearts is monitored by performing biopsies. These biopsy is also known as endomyocardial biopsies, where a catheter is inserted from one of the veins and it removes pieces of heart for microscopic examination. There's 3 to 5 samples that are removed and the pathologists look at those and they can tell if there's biopsy or not. Now that first show after a heart transplant, on average, it's between 14 to 18 biopsies. Only in that first year, right? There's a lot of boxes that are happening in that first cut. Between 2019 and 2023, there were prospective multicenter trials that validated donor-derived cell-free DNA as a biomarker for acute rejection. And back in 2022, expert review by the American College of Cardiology highlighted donor-derived cell DNA as a promising noninvasive alternative to endomychorial biopsies. And in 2024, as per the SRTR, the scientific regulatory of transplant recipients, there were 4,636 heart transplants performed in the U.S.A. So Max and I have known each other a while now. And Max, I'm going to ask you a few questions. You're here because you're the expert, so please tell us how you guys are doing these things. So my first question is, at your center prior to [indiscernible] DNA testing, how many protocol boxes were performed, that first year on your patients?

Thank you. Great question, Nick, and thanks for giving me a heads up on it actually was able to pull out our old protocols because it's been a while since we've only performed biopsies where we haven't used some noninvasive form of doing rejection talents. But is about a decade ago, our protocol was -- would entail, I think it was 17 biopsies, heart biopsies within the first year alone. And the protocol continues on through 5 years post-transplant. Ultimately, these are just the surveillance biopsies. Each patient would be subjected to invasive procedures during the first 5 years just by cortical for surveillance. That doesn't include for cause biopsies, biopsies that are indicated by a clinical change in the patient that is concerning for rejection as opposed to just doing surveillance.

Great, Max, thanks. And especially, thank you for telling us about the forecasts and the surveillance pipes differentiating there. Now most of us, I think you're the only cardiologists on this call. So most of us are not cardiologist. So please help us understand after you get that positive biopsy, what is the process? What is your treatment regimen?

So depending on a number of different things, the short of it is we almost will almost always going to treat for rejection. If a biopsy shows that somebody is having a rejection, there's two main forms of acute rejection, both you could either have purely cellular rejection, which is the white blood cells themselves are mounting in a direct attack on the heart muscle or you could have antibody immune rejection, which is another acute form of rejection where it's really the antibodies that are not white blood cells, but are created by white blood cells. If the antibodies themselves that go and basically plant a flag on the heart and notify the body that this is a foreigner. Either one of those forms of rejection can either occur by themself or can be mixed picture and demand which kind of rejection somebody is having -- they're going to be getting trade for at least at a minimum, 3 days in the hospital, but usually it will be closer to a week, especially if they were treating for antibody projection. And they get treated with IV steroids or for antibody rejection, we would be treating with even more invasive things like plasmapheresis, which is essentially like a large dialysis machine that's used to strain all the antibodies out of the patient. That, along with forms of chemotherapy that are used to prevent antibodies from recurring. So the treatments are pretty aggressive, and they're warranted if somebody is having a rejection. But I guess what I would say is the actual number of biopsies that come back positive for rejection is not very high compared to the number of biopsies we do. So ultimately, we do a lot of these invasive procedures to identify surveillance testing rejection that would warrant treatment. And it's really been over the last decade or more now about 13, 15 years now, we've had these different forms of molecular testing that we can use for noninvasive surveillance to really limit the number of biopsies we have to do in order to identify that patient who does warrant treatment.

Wonderful. Thanks for walking us through that. And also thanks for touching on like the second question I was thinking and asking like how long have you been using don't to drive cell-free DNA. So that's good about 12 to 15 years, you said?

Well -- sorry, Nick. So I would say initially, the molecular testing we were doing was the gene expression profiling. That was really -- when I first came when I first graduated from fellowship and took a job here. That was one of the first things I did was actually not replace our biopsy protocol, but added essentially an [indiscernible] protocol that allowed us to substitute these noninvasive molecular serum-based tests for what otherwise would just be a mandatory biopsy. And if the serum-based test was look normal, that was usually enough to forgo doing a biopsy at that time point. And that was -- initially, we didn't have sulfur DNA to guide us on this. We were using what I consider at the time was the best we had, but what I would consider a less sensitive and less specific assay to try to reduce the boxes or do a patients. But for maybe it's been about a decade in now. I think it was in like was it was around 2017, 2018 is when we really started using the AlloSure, which was kind of the first available sulfur DNA for doing surveillance. So we've been doing that for maybe about a decade, if that.

Wonderful. And from what you're saying, it sounds like you're using the self eDNA technology for surveillance, right?

Absolutely. I think -- I mean that's really where it's -- in my mind, the made power is, although a lot of that is based on the fact that we don't get the results back super quick. With our current cell-free DNA assays we have. And so from that standpoint, if you're looking to use a test that determines if somebody to make an immediate diagnosis something you'd want to do in the hospital with somebody presenting with a complaint and deciding whether or not we need to do a biopsy. If we had an assay where I could get a [indiscernible] DNA back, let's say, within 24 hours, then that would be a test that will potentially do when the patient presents. I use that as sort of the screening for rejection for somebody when there's this question about whether that they need to move on for a biopsy. That said, right now, our current assays were not available in-house, and they take usually at least probably 3 to 5 days to get the results back. And so by then, if somebody is presenting with clinical concern for rejection, you've either already empirically treated them and they finished the treatment before you can get the answer or you're basically waiting on treatment that ultimately, we could get a biopsy done and get the result back with that quicker. That said, just much the way we use a troponin or a BNP to kind of as a marker for an MI or for heart failure and somebody who's presenting to the ER with complaints that are concerning. I could absolutely foresee using cell-free DNA technology since we've seen that it does actually -- it does start to become abnormal sooner than when the biopsy becomes abnormal. It has a lot of characteristics that would make it a better rule out test for rejection even at the point of care if we could get a rapid result.

So you touched base on how waiting in those 3 to 5 days affects you, as you said, most of the times these patients are going to be treated empirically, right? Let's talk about the patient now. How does that waiting time the 3 to 5 days affect them.

So when we're using it for surveillance, I don't think it's much of an issue. The patient knows even if they were coming for surveillance biopsy, it's usually 24 to 40 hours before we have the results of a biopsy to tell them whether or not this shows any concern for rejection. So the patients are more than happy to just do a blood test. And even if it means waiting an extra day to find out whether or not there's any concern for rejection. If there is concern for rejection, if the assay comes back 3 to 5 days after we sent it and it looks abnormal, then we do need to. Then we have to put it together in the clinical context of that patient about whether or not we are concerned enough that this is rejection that's causing the abnormality with the sulfur DNA that we would then warrant getting a biopsy. I want to be clear, I would not -- the sulfur DNA technology as good as it is, doesn't -- it is not specific for acute rejection. So I don't necessarily treat patients with steroids or plasmapheresis. I don't treat them for acute rejection based off of an [indiscernible] DNA rather that test, lets me know which patient I need to be doing more testing in as opposed to if it's a normal test, then I don't need to go down the path of biopsies or any other kind of invasive testing. But so from a surveillance standpoint, Nick, getting an assay that's drawn in the clinic, whether or not we necessarily get it back 12 hours later or 3 to 5 days that I'll be very honestly, it probably doesn't change anything. But it is the testing we -- how do it. It would be very nice for our patients to be able to get the blood draw with the rest of their labs and they're drawing clinic. So I could absolutely foresee us using that kind of an assay, if we had a way to draw it in our hospital, regardless of how quickly a turnaround is even in those surveillance patients because it's -- frankly, it's a lot nicer than have it to them go to a separate lab to get a blood draw.

Good, good. And Max, you did start off by saying that a lot of the biopsies that were done in the past, the majority of them were coming back as normal. So talk about doing a procedure that really wasn't needed. So with this e-technology what I'm hearing is if it highlights, if it shows that there's possible rejection or some kind of injury, those are the candidate patients that you would move forward to do a biopsy. Am I hearing that right?

That's correct. That's correct. The power of this is -- it's a great rule out test for rejection. So if we do -- if we do a cell-free DNA assay and it comes back negative, there's really no reason for us to subject the patient to that biopsy. And so those 17 protocolized biopsies in the first year really get cut down to probably less than 10 anyway. We generally are still using biopsies for the first month or 2 after the transplant since none of the cell-free DNA technology has really been thoroughly evaluated in the early post-transplant period to know whether or not we can safely use that during the first month or so. But after 2 months, we pretty much exclusively just used for surveillance purposes, we just use a sulfur DNA technology now. And if it's only for the minority of patients where it comes back abnormal, will they then have to go and had and do biopsies. The rest of the patients are much happier, much better off not dealing with sort of the pain or the discomfort or the risk of the procedures of those unnecessary biopsies

Wonderful. Good. Well, Max, I have told -- and you know that here at IMDX, we do have a [indiscernible] essay that's based on droplet digital PCR technology that does not need to be sent out to the company's laboratory. It can actually be done in-house, and you guys can have the results back within 12 hours. So how do you think this shortened time to results will impact your patience and their quality of life.

Well, again, so from a surveillance standpoint, I'm not sure we'll change a whole lot other than them being able to get their lab drop at the facility where they get the rest of their labs drawn, which I think that actually shouldn't be understated. That is making patients make a separate trip just to get this one blood test is: One, it's a nuisance to the patient; but two sometimes it means we don't actually get the test done. Whereas when I have them in my office, I can get the lab drag. I have the ability to run the lab, I can do it all on site, which -- so that's a big bonus. But as far as the -- where I do see this in-house and sort of rapid availability of the results, changing, as like I was saying before, in patients that actually get a bit odor, which is not a trivial number of patients per month that are coming in, whether the transplant was within the last year or if it was 20 years ago. But when they show up with shortness of breath and you got some very other nonspecific things in the ER like an X-ray or an EKG and I'm not quite sure if this is -- none of them are really validated to determine whether that somebody is having projection and whether or not you need to keep that person in the hospital for 3 days to treat them empirically or you find out within 24 hours that their cell-free DNA is normal and that their symptoms are very unlikely to be related to rejection, I could see that very much helping the patients and that they won't have to sit around the hospital getting unnecessary treatments, but rather be able to get maybe more appropriate treatment and get out of the hospital quicker. So I do think that there a lot of benefit if we could get the test back quicker. And I'm not sure -- I was really pleased to hear when you're talking about this new product that you guys have that it sounds like we should have the ability to do this. But I don't know that we've necessarily sorted that out -- I'm totally with our lab yet, but that would be the dream would be able to get sell-through technology both for our inpatients and outpatients and be able to get it all done here at Loyola.

So you see -- obviously, there's going to be logistics, getting things into the lab and have training the personnel. But ultimately, do you see that this the contributions of such a test and having that availability to do this in-house would benefit your practice or your transplant center.

Absolutely. Yes. I mean [indiscernible] said, we're already using -- we've already largely adopted it as our primary surveillance for these patients. And I could see it becoming a primary way of making a diagnosis in a sort of for caused patients as well.

So Max, as MDs, we care about our patients, they're our family. I was presenting at [indiscernible] in Scottsdale and [indiscernible] raise his hand and ask the question, and he was from the transplant families. It's a volunteer organization, but he's the chair there. And he actually has a son, a 14-year-old son, who has received a kidney transplant. And he heard about the turnaround time and all that, and he goes, I have to tell you, Dr. Nick waiting in those 3 days, those 5 days, whatever they may be. It's heartbreaking for a parent because here's your baby. And we don't know what's going on. And will they have to go through another kidney transplant now. So from that perspective, it resonate. And then I spoke to more people from his organization, but he says, he's speaking, he's not just speaking for himself. He's representing this transplant families. So that's where we want to go. I mean we know we can make a change in the industry. But when you make that change, one patient at a time, what gives me satisfaction as a medical doctor. And I know you care about your patients, and I know you see that, too.

Well, I should say we do get a patients 24 hours, 40 hours after test inquiring about the results. I echo what you're saying. Absolutely.

Well, Max, that's all the questions I have for you. Do you have any closing statements or anything like that? Because after that, we can turn it over for questions from our audience.

Yes. No, I'm happy to just jump right into the other questions if you guys have them. I think that it's a pretty straightforward technology, at least in terms of from the clinical aspect is what it sounds like to me, if we can get this technology we've already learned to sort of be comfortable with and how to use it, but be able to use it more readily and in more patients. I think to me, this is very exciting and see it's this excitement that Max has about the industry and where we're going, that he's here today. He's not getting paid. He's doing it because of the love of the industry, they love for patients and to help advance the science. So with that said, thanks, Max, and I will open it up for some questions.

Awesome. Thanks, Dr. Nick and Dr. Liebo. Yes. So at this time, we'll be doing a Q&A session with all 3 of our speakers to our analysts who have joined us live to ask a question. I'll just give you guys a quick reminder to please raise your hand to indicate you have a question. So please hold for a brief moment.

We're still holding? Or is it frozen?

Yes. So we'll be taking the first question from Thomas Flaten at Lake Street.

Dr. Liebo, thanks for your time. Just one. I just want to clarify. So I mean, is your primary interest here in ruling out or ruling in a rejection depending on specifically in the case of a 4 caused patient?

So somebody who is coming in for caused, by that, I mean they're coming in with symptoms or there maybe their echocardiogram suggest that there may be a drop in their ejection fraction. So something to make us concerned they maybe have in rejection. My -- yes, the -- the purpose of it is really to look for both. I mean, we would do the cell-free DNA assay to look to see if there's any evidence that the heart is leaking more DNA than the rest of the body is -- and that's essentially what this technology is, right? It basically looks at the amount of DNA that's coming from non-self. And it compares it to how much DNA is floating on the blood stream that's from your own person. And if that percent that's going -- that's the DNA in your [indiscernible] nonself starts to go up relative to the rest of the DNA that your body is leaking, we become concerned there's some active process attacking the heart, whether it's rejection or vasculopathy or myocarditis or a heart attack, that we don't necessarily know from the results of this test. But what we do know is either that there's a problem at the level of the heart or not. And if that test in the forecast patient comes back, saying there's not a problem at the level of the heart, I'm not going to say I'm going to be completely done testing their heart. We're still -- we've generally sent off what we call donor-specific antibodies to see if there's any evidence that they may -- to help sort of make us discern just how concerned we are about possible antibody media rejection. But ultimately, that sulfur DNA level really does impact sort of our immediate concern about just how severe or whether or not something really is going on at the level of the heart. If it comes back negative, I'm generally fairly reassured that their symptoms may be more pulmonary in nature. There may be -- I have to look for something else. I'm not really too concerned about rejection if that sulfur DNA is normal. Now that said, I'm very interested in that patient. There's a reason I'm doing it is because I'm concerned for us. So I'm very interested in making the diagnosis of rejection if they have it. If that sulfur DNA level comes back abnormal in that forecast patient, then that patient absolutely is going to be getting dosed with IV steroids and then he's going to undergo a biopsy and if that biopsy doesn't confirm that they have rejection that would -- is going to improve from the steroids have given them or warrants antibody treatment. Then the next test, we're probably doing in that patient is an angiogram to see if they've developed any vasculopathy or any corneal lesions that would benefit from a stent. But ultimately, that cell-free DNA assay, whether it's in the surveillance patient or if it's in the patient for cause, it's really helping me determine whether or not I need to continue to look at the heart as a source of the problem or I can look into other organ systems.

Sorry, Thomas. Max, allow me to chime in here real quick. So Thomas, the way the industry has trained us -- many doctors practicing transplant physicians is to use these tests as rule out because they've got high negative predictive values. So with that, that's what you're doing, you're ruling something out. What we have seen in kidney, we've got a very high positive predictive value. And that's what will give confidence to the physicians to go, okay, now I'm seeing high positive value. So when I see this above the threshold, now I can start trusting it that I can rule it in that something is going on. That trust will eventually happen. But right now, the industry is exactly like how Max explained it. He has to use his judgment as the physician there, but ultimately, they're all rule out high rollouts.

And just one more follow-on, if I may. Does it matter to you Dr. Liebo, if the test has a specific ability to discriminate between cell-mediated versus antibody-mediated rejection or does it not matter at that kind of initial case. You just want to know if there's a rejection period?

That's correct. The short of it is there's -- it cannot tell me with any kind of certainty, whether it's cell-mediated or antibody mediated. We do have some idea there the literature has suggested that antibody [indiscernible] rejection generally presents with a bit higher of a cell-free DNA elevation than the self-media rejection, but there's a lot of overlap. So at the end of the day, it's -- this test is basically to let us know whether or not as Nick put it, it's a rule out test. If it comes back negative, it's we -- that's very powerful in sort of my in my clinical assessment then about helping me shape my clinical assessment about what is going on and where an invasive test as needed and where it's not. And the -- but if it's abnormal they if it's elevated, then it's just letting me know that I need to go ahead and do that biopsy to determine which form of rejection this is, I need to follow. I need to get -- if it hasn't been sent already, we need to send off antibodies for this heart to see if there's any suggestion that the patient has now formed antibodies to his own heart. And we would then use that information to determine whether or not we need to be treated for further treated for rejection or we need to continue to look within geography or an MRI or look with other things to figure out why the heart is leaking if it doesn't look like it's actually a rejection.

Our next question comes from Mark Massaro at BTIG.

Great. Thank you. So doctor, this is a great presentation. I just wanted to get a sense, it sounds like my impression is that you might have been using the CareDx products based on your remarks earlier. And if you were to make a change, would this be something that you would have a significant influence in making for your entire health system? Or would this be something that maybe you might start using, but maybe can you walk me through how a change in your health system would work across multiple clinicians?

Yes, I will do my best with this. As far as -- I have experience using both the CareDx product as well as the Natera. And in fact, that's really where we've kind of grown to become very comfortable using sulfur DNA technology is because we've -- we participated in both of those registries previously, the SHORE registry as well as the PROTECT registry. And so we've accumulated a lot of our patients even when they were still getting their biopsy protocols for protocol as part of the registry, they were getting these assays. And so I was able to then sort of see how the assays are matching up with biopsies or in those patients who then had graduated out of our biopsy protocol was able just to get used to managing these patients based off of their whether -- whichever product, whichever self-port DNA product we were using. As a health system, we do not necessarily. We are not beholden to either one of the companies. And I would say, I think we probably do about 50-50 in terms of sending out Prospera's versus [indiscernible] when it comes to our current available sulfur DNA products that we're using. I personally can't say much about how things would go with the whole health system. What I could speak for would be loyal itself. And to be fair, Loyola is, I believe, the only at least for heart transplant, the only facility in our health system. Trinity health, I don't believe has another heart transplant center. If they do it, there's just 1 or 2 on the East Coast. It's not much. But I would assume that they would -- they need transplants in or would kind of adopt this the same way that I foresee myself and my other 2 colleagues here at Loyola using it and saying, we don't really have a preference over the cell-free DNA technology terms of there's not been one study showing that one is superior to the other but rather what's the most convenient for our patients and what can we -- and what's the most clinically helpful, useful. And in this case, that's why I say I would foresee us using this exclusively Ultimately, if we got -- if we had the ability to drive this and run it in our own hospital and we're getting results back, 3 to 5x faster than we do other -- our current whatever call logistics,

Okay. That makes -- that's really helpful. And then I would love to ask about the economics of testing, and this might not be something that you have to deal with because you're caring for patients, which I really appreciate. But if you could perhaps take a stab at this. So in the event that your system was able to benefit in the favorable economics of surveillance testing,is that something that you think about? Or is that maybe the CFO of your health system or our program director because as an analyst, sometimes we -- of course, we think about how -- some clinicians could be financially motivated to make a switch. And if you took it in-house, I think you could benefit from the economics yourself rather than sending it to CareDx or Natera. So maybe just walk me through maybe the economic argument, if that even is something you think about? Or maybe it's something that someone else that your system thinks about.

Yes. Thank you for the question, Mark. I would say -- I personally, as you alluded to, I really more in the exam with the patient, and I'm kind of more focused on medical decision-making and what is best for the patient in terms of their medical care and their comfort and their convenience. So the financial side of it doesn't cross my mind all that much. I tried not to let that sort of sway me from doing the right tests on patients. That said, absolutely, there's somebody here at Loyola, Minette Trinity, who would very much, I'm sure be in favor of if this was something that was financially better for us than using another product or if this was financially better for the health care system or for our system than doing a biopsy, I'm sure they would only further encourage this is to get accepted as a tool here, we could hear at Loyola. But I'm not sure, Nick, you may actually have a better feel for -- to be host, there was a point when I first started over a decade ago where I think I did know what the cost of a biopsy was and how much the hospital made from a biopsy versus what it cost for AlloMap or an AlloSure back then. But I'm not -- I don't have those numbers off the top of my head right now.

Max, I'm with you on that. When it comes to economics and numbers, I respond to those questions. If I'm out with sales, they can answer them. Now we've got our CEO. So Josh, I don't know if you want to take that?

No, I think the answer was perfect. Clinicians decide if it's useful for patients. And that's the first question that has to be answered once that question has been satisfied, then it becomes a CFO question. Can they afford to bring it in-house? Does it make sense for their system. But the first hurdle is always convincing clinicians that this is the right thing for their patients.

Maybe last question for me, Dr. Liebo. I know there's been -- at least in the last couple of years, there's been uncertainty with respect to surveillance testing in heart and kidney and lung testing. And that, I think, is because there's been some discussions with the Medicare group and some other groups in the government. But I just wanted to get a sense for: One, were you aware of any of that Medicare limbo? And two, did you make any changes to your surveillance protocol? And then three, now that, that Medicare is clarified and finalized? Maybe can you walk me through how important developing a surveillance protocol is in your practice?

Yes. Thank you, Mark. It sounds like you could maybe educate me some on this because I'm actually not real -- I'm not real familiar with the issues with Medicare and surveillance right now other than I can tell you I've -- for as long as I've been doing this, especially when it's covering for one of my colleagues, the fit there are definitely things on our surveillance protocol not usually about the heart itself. It's usually more about the surveillance we're doing for cancer or for other infections, things like that and the interpatient with transplants. But there are definitely some testing we have on our current protocols that routinely lead to us having to do sort of peer-to-peers or appeals to the insurance companies to pay for it. But for a concern about is there's really not data that supports a lot of this stuff that's in the servant testing of patients post transplant. So I guess I would say I'm not -- I wouldn't be totally surprised to hear that there's -- this has been coming up about whether or not this is a good use of resources that patients are getting full body CTs every year and things like that. But as far as when it comes to the surveillance of the allograft, I'm not -- I wasn't aware that there was a whole lot of issues with saying that we're not sure that there's actually value and I think that all the guidelines are pretty clear. That at least for the first 5 years after a heart transplant, the risk of acute rejection isn't insignificant and it's time and again in the guideline documents, it's been recommended that we're monitoring patients like weekly for the first couple of months after a heart transplant and then starting to reduce the frequency after that, but still relatively frequent like monthly assessments for the bulk of the first year and then at least quarterly for the next few years. So I don't think that we're going to see surveillance testing of the -- for rejection going away. I think that what we're seeing is a big change in the modalities we're using instead of being these Frankly, I say this with all respect, I'm the one who does the procedures here, but the biopsies are fairly barbaric, and they do come with the risk of complications not necessarily a high risk of life-threatening things, but you can actually damage the heart and you just gave somebody. And you guys are all aware -- Nick mentioned how there's only about 4,000 transplants a year. And there's probably like 0.5 million people that would potentially be better off with one here. So ultimately, these aren't things that are easy to come by. And when you get one, the last thing you want to do is run it. And so I think that for surveillance, at least for the heart rejection, I think that we -- I don't foresee a problem getting -- having -- I think these assays, whether it's IMD or if it's the ones that are already presently in commercial use, I don't see them going anywhere. I think that they're actually just going to more and more take over the biopsies and reduce the risk. The unnecessary biopsies we've been subject in our patients to over the years.