Humacyte, Inc. (HUMA) Earnings Call Transcript & Summary

Good morning, and welcome to the Humacyte Virtual KOL Event. [Operator Instructions] As a reminder, this call is being recorded, and a replay will be made available on the Humacyte website following the conclusion of the event. I'd now like to turn the call over to your host, Dr. Laura Niklason, Founder, President and Chief Executive Officer of Humacyte. Please go ahead, Laura.

Good morning, everyone. Thank you for joining us for this webinar, where we're going to be providing a number of case reports actually that are drawn from our treatment of trauma patients with our engineered vessel and also from some expanded access cases. During this call, you'll be hearing directly from surgeons, who have treated patients using our engineered blood vessel and their outcomes and their experiences. Just to provide a little bit of background on Humacyte's technology for those who aren't already familiar. Humacyte makes engineered blood vessels from human cells. These are human arteries that are grown to be 40 centimeters in length and 6 millimeters in diameter. These arteries are manufactured, as I said, from human cells, but the product that gets implanted into patients is actually acellular because after we manufacture the arteries from human cells, we then remove the cells from the artery, which leaves behind only the human vascular extracellular matrix proteins. These human vascular proteins constitute the blood vessel that's implanted into patients, in this case for the treatment of traumatic injuries. Importantly, because these blood vessels don't contain any cells, they're nonliving, and so they're available off the shelf anytime surgeons need them. In fact, they can be stored at refrigerated temperatures for up to 18 months after manufacturing. Again, because the vessels are noncellular, they also don't induce an immune response in the patients. In fact, we've treated nearly 600 patients over our clinical development program, and we have not seen a single episode of clinical rejection. Also importantly, after implantation, Humacyte's engineered blood vessels repopulate with cells from the patient and become a living artery over time. They really become the patient's own blood vessel. This is a short summary of our manufacturing procedure, which I won't go into any detail here, except to say that we start with a small vial of human vascular cells, [ faw ] those cells and grow them and then seed them onto scaffolds. These are biodegradable polymer scaffolds that are the size and the shape of the artery that we ultimately grow. We grow using technology that Humacyte has developed. We grow 200 arteries at a time in a highly automated process in our manufacturing suite that's contained in our facility in North Carolina. During a 10-week process, cells are grown seeded on to the scaffold, the cells then proliferate and secrete extracellular matrix proteins. And while that's going on, the polymer scaffold dissolves. After the decellularization step, the engineered artery is contained inside the bioreactor bag in which it was cultured and that bioreactor bag with the artery is sterilized and then shipped to hospitals so that it can be used by surgeons and patients at the time of need. As far as who you'll hear from today, you're going to hear from 3 investigators, all of whom participated in our V005 clinical trial, evaluating the safety and the efficacy of Humacyte's bioengineered vessel in the treatment of patients with traumatic vascular injury. The first surgeon you'll hear from is Dr. Ying Wei Lum. He is a surgeon at Johns Hopkins School of Medicine, and has treated a number of patients having both acute community-acquired traumatic injury and also traumatic injury that was associated with the treatment of tumor resection in some patients at Hopkins. Next, you'll hear from Dr. Charles Fox, who's at the University of Maryland School of Medicine and is also a retired U.S. Army Lieutenant Colonel. Dr. Fox works at Baltimore Shock Trauma and will be presenting a case of a patient who was cared for in Ukraine during a humanitarian effort that Humacyte undertook in cooperation with the Ukrainian government after the Russian invasion of that country. Lastly, we'll hear from Dr. Rishi Kundi, who's also at the University of Maryland School of Medicine. He's a vascular and trauma surgeon, and he will present an expanded access case. This is a trauma patient who sustained his injuries after the closing of enrollment of our V005 clinical trial, but who, in fact, suffered multiple complications with previous attempted revascularizations and who received the Humacyte's engineered vessel as part of an expanded access or compassionate use program. And with that, I'd like to -- now I'd like to turn it over to Dr. Lum, who will talk about the first case.

Good morning, everybody. My name is Ying Wei Lum, I'm a vascular surgeon at Johns Hopkins. During the process of the trial, we enrolled probably about 10 patients into the study. A fair number of these patients who were patients that had to get vascular repair during iatrogenic cases. And by iatrogenic, we mean cases where the intention was to do something else. But unfortunately, there were some sort of operator injury or injury to the vessel that required vascular reconstruction. So just as a quick introduction to some anatomy 101 for the purpose of this discussion. I'd like to draw attention to the picture on the right over here. And as you all know, arteries bring blood from the heart to the toes, but veins bring blood back from the toes back to the heart. And in the leg, I'd like to draw your attention to these 2 veins, the femoral vein and the great saphenous vein. These are the 2 major veins that bring blood back from the feet back towards the heart and -- in terms of venous drainage. Now the saphenous vein is the one that's most commonly used for bypasses and reconstruction and things of that, when a person gets a CABG or a heart bypass, the vein that they use is a saphenous vein. When as vascular surgeons when we do bypasses, we also use the saphenous vein. That's because the saphenous vein is closer to the skin, it's easy to harvest and it's generally pretty long. The femoral vein on the other hand, is a little bit deeper inside the body right next to the muscles and is right next to artery as well. All right. So our first patient is 61-year-old man. He has a history of Li-Fraumeni syndrome, which is a genetic condition that predisposes 1 to developing a lot of different kinds of cancer. And this gentleman had a history of prostate cancer, bladder cancer, lung cancer that also had metastasis to the brain. Now these regions and all these other cancers have all been treated and the only cancer that he had left at the time of presentation was a sarcoma in his left eye that was treated with radiation therapy and then subsequently referred for surgical resection. During the operation because of how close the artery was in relation to the tumor, there was an injury to the artery as the attempts to peel off the artery from the tumor was being made. And at that time, the defect and the size of the defect on the artery was a little bit larger than expected. And as such, it was felt that the patch repair would not be ideal. So in this case, we're going to use a conduit for reconstruction. A couple of things come into play in terms of decision-making. But first of all is can we use a saphenous vein. In this case, we did not want to use a saphenous vein because the patient was also going to get the femoral vein ligated. So if you harvest both the veins, then you're going to have very impaired or significantly impaired venous drainage from that leg. And that leg is going to be at risk of significant swelling and complications related to that. The other concern is in this case, when the patient was being operated on by the orthopedic oncologist, she had experience in the past where if we use vein from the other leg, she's had cases where there were seeding of tumor cells on to the contralateral extremity and so she did not want that to happen to this gentleman either. So as such, we decided to use the Humacyte ATEV. And this is the couple of intraoperative pictures. Here, you have the silver clamps on the blood vessels, and you see the leg of defect was probably just over an inch or two, and on the right side, you have the reconstructive picture of the human acellular graft right in -- as a bypass in between the 2 vessels that was reconstructed. So this graft was implanted as an inter precision graft for direct in-line flow. Intraoperative studies that were done confirmed patency of the reconstruction with no complications noted. Of note, this case was also deemed to be a little bit higher risk for infection due to the history of radiation that destroys a lot of the tissue and makes it a little bit more susceptible to postoperative infections, as well as a degree of venous congestion since we also had to ligate that vein and sacrifice that vein on the same extremity. This is a time line for the case subsequent to what was done. On the right over here, you have a couple of pictures, which are ultrasound images that show a very nice transition from native vessel to the graft and then to native vessel again. In fact, can barely even see where the transition is on the bank end, the posterior aspect of the imaging. And there's just a vascular duplex wave forms to show that there's nice possibility and this triphasic waveform that we see in these graphs due to the compliance of the vessel. So this patient generally did well. It was implanted day 1. We did some ultrasounds to confirm patency of it on day 1. That was also done on day 30 to confirm patency. The patient had a postoperative seroma, which is just a fancy word for fluid collection, then that's usually drain by drain, but the drain fell out and the collection continued to decrease in size with no subsequent intervention. And then the patient continued to live on for about 3 years. And at the time of his passing, he had a metastatic lesion that went to this lung, but throughout that whole time, the graft remained patent. There's no infections. The patient did not lose a limb. There were no aneurysms or degeneration of the graft, and there were no adverse events related to the operation. So some key takeaways that I thought were nice to summarize in this case. This was a -- graft was implanted in a -- not a typical traumatic case, but iatrogenic case where some form of vascular reconstruction was deemed necessary, but the saphenous vein was not available or not ideal. The patient was considered high risk for infection due to radiation and congestion from the venous drainage. At the end of the day, the patient had a graft that remained patent without any complications. And I think the last and key thing is to note is that this is pretty easily available off the shelf. You don't have to wait [indiscernible] it for 30 minutes and do a bunch of fancy flushing's and time-consuming things to tow the graft out. It's got excellent outcomes at least in my experience for these kinds of cases when vein -- autologous vein is not available. Thank you.

Thank you, Dr. Lum. That was a great summary. I think we should move on now to Dr. Fox's case. And then Dr. Kundi's case.

Okay. Good morning, everyone. Laura, thank you for the nice introduction and the opportunity to speak about tissue engineering on the battlefield. And I'm going to advance my first slide. Well, the military offers some unique challenges for limb salvage and tissue engineering gives surgeons another option on the battlefield to try to reduce amputation rates, which are enormously high because of the incidence of infection, and this is an example on the upper right of a hospital that I served in Afghanistan, where we were very close to the forward edge of the battle area. And you can see the type of extremity wounds that you see with high-energy blast pipe munitions. They lack a good soft tissue coverage. They challenge us from the standpoint of bleeding and hemorrhage control and resuscitation and challenge us to put in a conduit that will resist infection, but save the leg by restoring blood flow. I'm going to talk about a humanitarian project that Humacyte was involved in to assist Ukrainian surgeons in vessel reconstruction and reduced amputation rates. In coordination and approval from the FDA and the Ukrainian Ministry of Health, the ATEV was shipped to 5 hospitals in Ukraine, Benicia, Dnipro, Odessa, Kyiv and Kharkiv, which were notorious for getting bombardment and missile attacks in the east side of the country. And I happen to be there at the time with another organization and met a number of these surgeons who use this product and now speak to their ability just like our U.S. colleagues and our other European colleagues that they really understood graft reconstruction, hemorrhage control resuscitation and quickly adapted to the unique challenges in their war zone, which notably was the lack of air superiority in many of these soldiers with extremity injuries, were kept in one area for an extended period of time. After proper training, the study started with a V17 project, and I want to illustrate the use of this ATEV in a 29-year-old Ukrainian male to an extensive number of blast type injuries from the hip to the lower extremity. The extremity was pulseless, the tissue was ischemic and without vessel reconstruction, he would have undoubtedly lost that leg. The imaging demonstrated that the injury was to the common thermal artery, which is an important artery route for reconstruction. Without that, there isn't sufficient blood supply to revascularize the lower aspect of the leg. And the CT scan shows the extensive metal fragments that are surrounding the artery with arterial disruption. And so the ATEV conduit was a 3-centimeter conduit, which was placed interposed into the common femoral artery because of a lack of any saphenous conduit. As you can see, there's so much extensive soft tissue damage that we really need another option that comes off the shelf especially to expedite the operation and to satisfy the reconstruction when there isn't another option. This patient was followed throughout a 6-month period, both medically treated with antiplatelet therapy, wound coverage, wound healing and ultrasound that demonstrated patency of the ATEV conduit. There was no imputation report -- performed on this patient. He was able to save his leg, and you can see from the screen right full weight-bearing with extension inflection of the extremity. People who experience penetrating wounds have had this conduit placed in this position very commonly and also common to the popliteal artery where the amputation rates can be very high. Interestingly, this conduit seems to be resisting infection and allows for proper soft tissue coverage to be done. And over an 8-month follow-up period, this patient was able to walk downstairs. Thank you very much for your attention.

So after that, we're going to go to the third and last case. This is going to be presented by Dr. Kundi from University of Maryland Medical Center and Baltimore Shock Trauma. Dr. Kundi, -- the -- I know you joined us recently. The control for the slides is on the lower left. So if you can see some as well arrows on the lower left there, you can advance the slides under your control.

Got it. I'm sorry that I'm late. As you can probably tell by how I'm dressed, I'm on vacation right now. And the fact that I wanted to do this while on vacation should be some indication of my enthusiasm for ATEV. So this is a -- let's see, lower left.

So Dr. Kundi, I can just advance for you if you want to [indiscernible].

Okay. So let's go the first slide then please. Okay. So this is the case of a very unfortunate young man who came in on May 27 with multiple gunshot wounds to his trunk and one to his left groin. His injuries were really quite severe. He had a pretty destructive liver injury. He had a massive diaphragmatic injury and a moderate lung injury. Later on that day after he -- I mean, after he presented, he went fasciotomies of the thigh and calf as well as exploration of his abdomen. Because he -- his first procedure was exploration and just plain ligation of his common femoral vein, which could not be reconstructed, his external iliac vein was ligated in the laparotomy and his profunda femoris vein was ligated. So his ballistic cavity that actually just tracked under his inguinal ligament was the size of my fist. So this was a very, very destructive injury. At that time, he did not have evident arterial damage, but because presumably with the cavitation effect his left external iliac common femoral, superficial femoral, profunda femoris had all been thrombosed, so they had to undergo open thrombectomy. He went back to the floor and -- advance, please. And several days later, up to 6 days later, I think, he started having substantial arterial bleeding from his groin incision. In the interposed days, he had become bacteremic with Klebsiella and Serratia. And shortly before demonstrating these signs of arterial bleeding from his groin, his midline and decision had fallen apart. So he had an open abdomen at that point. He had essentially a massive inflammatory response to these 2 bacteria, which are unfortunately quite common in our ICUs. When we took him back on the fourth, he had a complete blowout of the arteriotomy. So even though he did not have an arterial reconstruction, his infection had proceeded to the point where the simple to suture repair of the arteriotomy through which he had his embolectomy had fallen apart. And in fact, the arterial wall was very clearly infected at that point. And so bovine carotid artery the artegraft was used to reconstruction left external iliac [indiscernible] profounda and then a jump graft was created through the SFA. And we thought everything was fine. Two days later, he demonstrated some signs of bleeding. His hemoglobin fell and he started having some fullness of his operative site, went for CT scan and that showed that he had hemorrhage from the reconstructed left femoral complex, really specifically from the proximal anastomosis. We went emergently to the OR and found that in that proximal anastomosis between his native external iliac and the bone graft, the anastomosis had fallen apart. And on exploration, no infection was seen at the time by which we mean no obvious purulence, right? So there's no pus, but the order is clearly very inflamed, and it was falling apart. And so that segment of the common femoral artery, which had been very clearly inflamed and falling apart was resected and an additional length of bovine carotid artery was implanted. I should add at this point that on the fourth, during the primary reconstruction exploration was made of his bilateral saphenous veins, and they were very, very small and unsuitable for use. After the 6th, he seemed to be doing much better. He had some fever on and off, but overall, his white count was tracking down. It never got below 16,000 with the normal being 12,000. So it was definitely prolonged persistent signs of systemic inflammation, but the femoral incision looked to be healing and throughout he had good pulses in the foot. On the 19th, his fever after several days of being absent spiked and personally, my worry that this repair had for the second time started to bleed prompted a really kind of a preemptive CT scan that show that, in fact, there was bleeding from the anastomosis. And this time, there was very clearly a fluid collection, which was consistent with and in fact, in hematoma. So this had been bleeding for some time. And as the blood had been collecting rather than going out of the incision, the blood had become infected and had turned into an abscess. So we were kind of at this point, at a loss because this is an infected field, resection of the conduit was absolutely indicated, there was no way that we could just do nothing. But unfortunately, because of the extent of the infection and the fluid collection every route to the target artery, which in this case would have been the mid superficial femoral and perhaps even the mid profunda artery was going through an infected field. And what that meant was that this prosthetic was completely contraindicated. This would be putting plastic right through pus, and that was guaranteed to get infected. If we have simply resected the infected artery, the boy would have lost his leg. And so after thinking about it for some time, I contacted Humacyte and the FDA, and we made an application for a compassionate use exemption. We just completed the trauma trial at our center and after thinking about it for a long time after consulting with Dr. Fox and some of my other partners, really, the ATEV was the only practicable way to keep this boy from losing his leg. Now -- next slide, please. Now because the process was going to take 36 hours or so, what I did was initially, put a temporizing stent, a covered stent across the area of bleeding, which turned out to be the anastomosis to the profunda. And this was intended as an entirely temporizing measure, but it did buy us time for the compassionate use to be approved and to get the graft. So on the 21, we were able to reexplore. We took out all of the bovine graft. We took a length of the ATEV, and we created once again from the external iliac to the profunda femoris and then a jump graft from that graft to the superficial femoral artery, essentially reconstructing his natural anatomy. The angiogram on the far right of this slide, you can see is the completed bypass, which shows good in-line flow. He had a good palpable pulse at the completion of that case. Next slide, please. So it has been, obviously, a couple of months since then. Our 6-week follow-up scan showed that the graft was completely patent. There was no evidence whatsoever of any kind of collection, no evidence of really any inflammation in the area. He had some heterotopic ossification, which is extremely common with a destructive ballistic injury. But really of note, the radiologist report did not talk about a bypass graft. He simply mentioned the native vasculature meaning that at least on CAT scan, there was no indication that the patient had, had any kind of vascular reconstruction whatsoever. Now this is something that we have seen on ultrasound several times in our center anyway that after a certain amount of time, the graft is indistinguishable from native artery. But this is the first time that I had seen a CT scan report where the radiologist was unable to tell that there have been any kind of reconstruction. Next, so in sum, the ATEV was implanted in a patient with no saphenous vein available, not only with evidence of infection, failure or previously implanted graft, but this was the third reconstruction in a patient who was on very broad spectrum antibiotics, was demonstrating evidence of continued bacteremia, and I should add that within 2 days of the excision of the bovine graft and the implantation of the ATEV, his fever broke, and his white count came down to normal within 4 days. And he remained on what we call suppressive antibiotics for the long term because he did have a very varied data infection. But currently, the last that I saw him, he was getting ready for his fasciotomy incisions to be skin grafted. He was walking, the boy was going to lose his leg, and he is walking. He still need some more reconstructive surgery for his abdomen, but this is not only as good as we could hope for, but this is a better outcome than I had in mind when what I did apply for the exemption. And the really, as mentioned in the last bullet point here, the ATEV came as a 40-centimeter graft, which allowed us to make a complex free construction. We're not just talking about an inner position graft or even a bypass, this was reconstruction of a fairly anatomically complex area in the leg, and it performed beautifully. And I really, like I said, could not have hoped for as good an outcome as we ended up having. All right. Next -- any questions from anyone.

Thank you, Dr. Kundi. So now we will conduct our question-and-answer session with our speakers.

[Operator Instructions] So our first question comes from Ryan Zimmerman of BTIG.

Can you hear me okay?

We can hear you.

All right. I appreciate all the surgeon participation. I guess, I want to take advantage of the fact that the surgeons are here and get their perspective on how you're thinking about ATEV and in a post-approval world. And so as you think about pulling the ATEV off the shelf, where do you think the appropriate cases are that qualify for its usage. I mean we've had really good case studies in terms of infected cases or war prone areas. But as you think about it in more of a commercial setting, what's when you think about it as maybe a first-line treatment, what type of case does that look like? And then just as a follow-up, is it always secondary patency that we want to look for? Is that ultimately, in your guys' mind most important, when you think about the durability of these products? Maybe you can just comment on kind of some of the functional outcomes or metrics that you look for in deciding which product to use off the shelf.

I'm happy to be the first one to address this if no one else will. In the -- after I use it in this case that I spoke about the FDA wanted some follow-up and I'll tell you what I told them when they just flatly asked my opinion about the product. As far as thrombovascular surgery, this is going to be -- it's going to revolutionize the field. The prevalence of unusable saphenous vein in our patient population in Baltimore is exceedingly high for whatever reason. And as to your other question, about more chronic peripheral arterial disease. These patients, generally speaking, are not -- the majority of bypasses done in this country, now after the advent of endovascular, I'm definitely open to correction for my colleagues here. It is not an easy first-time bypass. There are patients who have undergone endovascular revascularization, very often, they have had previous bypasses. They do not have veins. This isn't -- this is in the 1970s, everyone doesn't have a saphenous vein, it's just waiting to be used for fem-prof. And this will take the place of prosthetic period. I think if it was up to me, and this product is available, I don't think that I would use prosthetic. The number of times I would use prosthetic for a bypass case if ATEV was available, would be less than 10%.

I think Dr. Kundi articulated all of my comments, but I'd like to just say a few things in my own words because I realize in a military conflict, that's a very small niche of commercialized patients. But any time I'm worried about infection or speed of the operation, I think of alternatives of harvesting the saphenous vein. The saphenous vein is obviously our go-to conduit, but many times, time doesn't permit, or the injury doesn't permit, or the infected field might be a consideration for some alternative. And I personally don't think there's any other alternatives to the ATEV right now. This doesn't require much preparation. You basically cut it out of the plastic tubing, and you flush it and you begin selling with it, and it's got great handling properties. So it's a very fast opportunity to begin your bypass with minimal aggravations. And when time is of the essence, this is really important or when education level is of the essence, it's very important because many general surgeons don't always feel comfortable harvesting the saphenous vein and then embarking on to a difficult bypass operation. It just becomes a bridge too far. So this allows us to do something that's given very good results and seems to be remodeling into the artery and resisting infection. So I think it's going to be my go-to conduit in those situations.

Dr. Lum, do you want to add.

Yes. Thank you. So I do a lot of complicated operations at Hopkins where involve tumor reconstruction or abdominal reconstruction of blood vessels and things like that. And in those situations, sometimes you worry about contamination. But to allude to the saphenous vein, I think even though saphenous vein may be low in those situations, the size is not ideal. So the saphenous vein is about 3 or 4 millimeters, maybe 5 millimeters at best and sometimes you want the reconstruction that is 6, 7 or 8 millimeters in size depending on the -- on what you're trying to reconstruct. So I think the benefit of this over that saphenous vein as well as the size reconstruction. And as Dr. Kundi and Dr. Fox have talked about the ability to resist infection, I think, is pretty paramount over here. You could put it in effective fields, and they seem to do pretty well. So I think although the indication is for trauma, I do think that a lot of people will be using it for all sorts of other reconstructions whenever infection or size is a consideration.

Very helpful. And if I could ask maybe a follow-up, if that's okay, Laura and team. Just in terms of commercial adoption. One, do you see any impediments to adopting it at any of your facilities that we need to consider in terms of the timing of the rollout, be it -- and I would assume most operating rooms have refrigeration all set up and everything from an infrastructure standpoint needed. But how do we think about kind of how much maybe you'd keep on the shelf, for example, in terms of the volume of cases and just kind of that initial interest level in taking the product on?

So Ryan, I'll try to answer that question. As we've discussed previously with investors and analysts, as an engineered artery, the Humacyte product is not going to be cheap, right? And so we will have to do several months of work with value analysis committees at each hospital at each Level 1 trauma center, to show them the data, to show them the outstanding clinical outcomes, particularly as compared to synthetic grafts; and also to walk them through the budget impact model, which we've constructed, which really shows enormous cost savings to hospitals in the setting of trauma because by using our vessel, particularly as compared to synthetic grafts, we show that a lot of amputations are avoided, a lot of wound infections and sepsis events are avoided. And those savings to the hospital by avoiding those complications, we think will really support adoption at most Level 1 on trauma centers. As far as how many copies of our vessel, each center would stock, I think that's difficult to predict. I think in busy centers, we might expect them to stock 3 to 5 ATEVs. What I can say is that, clearly, for the trauma indication, the vessel has to be there on site. It's not like it can be ordered and shipped. So clearly, trauma centers are going to have to maintain some level of stock of the product. But that said, we can also ship from our facility and provide overnight shipments. So we're not anticipating that hospitals will have to stock 10 or 20 of these, but to start, perhaps 3 or 5. But again, that's a guess.

Our next question comes from Kristen Kluska at Cantor Fitzgerald.

Appreciate your perspectives. I have 2 questions, if I may. The first, I'm not a vascular surgeon by all means, but it seems that these 3 case studies presented are on the more complex side in terms of the degree of what you're used to with these injuries. So given the success you had in these very complex settings, how would this impact the likeliness to use this and maybe moderate or less complex trauma settings as well.

I want to talk a little bit about a paper that I wrote with Professor Gene Moore. We had a lot of knee dislocations in Colorado and usually, that disrupts the popliteal artery and leads to a very high amputation rate. But the artery that's injured is right behind the knee and if you put the patient in a prone position, you can get a really good outcome with a very short interposition graft like the graph that I showed you from the Ukrainian soldier. When they're very short, they tend to work really well. And you can minimize the number of incisions that you have to make even on a relatively isolated trauma patient with a very small injury, but a very -- but an injury that has a high amputation rate. So we like to put them in the prone position, which makes it very hard to harvest the saphenous vein, but we had excellent results with it. So I think there's another opportunity to use it for patients that don't have war injuries, but just need a very short graft.

I would say the use will depend on our comfort, I think, over time. I don't think this will overnight replace saphenous vein. That's probably not the goal of the graft. But I do think that for at least all the complex reconstruction schedule, I probably use it almost all of them instead of saphenous vein for any of the oncology reconstructions just because the size is so much better than 3 or 4-millimeter saphenous vein, probably use it for all the upper extremity stuff doing the subclavian axillary reconstructions. And we've only so far been talking about arteries. Certainly, I do some venous reconstructions as well, and I probably would try using this in those situations once the graft becomes available. So I think this -- the way I see a graph, I see there's something that's a little bit more infection-resistant and a little bit of a better size match than saphenous vein for the larger blood vessels.

I also anticipate using it in the future for dialysis access. A number of the dialysis patients that I treat don't have any vein anymore. They sort of have used up the available vein in their upper arm and the lower arms in my patient population on the East Coast is pretty nonexistent especially with diabetes and renal failure combined. So given its opportunity to resist infection, remodel and be a very easy conduit for handling, I think there's going to be a lot of dialysis access surgeons that will be interested in this.

I want to go back to something Mr. Zimmerman asked and answered that and this question at the same time. We talk about primary patency, secondary patency, but in the context of peripheral arterial disease, those are very ambitious endpoints. Really what a lot of our patients, what we are interested in is amputation-free survival and just basic claudication functioning. And so if this graft has good secondary patency, yes, that's excellent. That's wonderful because that is a threshold that is actually higher than the one that really, really is the criteria on for utility. I think that this graph is going to be used all the time. If you look at how often we go through prosthetic, you will get some idea of how often we will use this graft, which is at this point, at least in our center, a majority of the vascular surgery that we do.

Okay. And I just wanted to ask about the potential to use this product for wars. When we think about the Ukraine experience, the data looked very much in line with what was reported in the actual clinical trial. And obviously, on the war front, you don't have access to as many surgeons' medical professionals as you would in a hospital setting here. So can you talk about the appetite or the interest for thinking about utilization of the ATEV in those situations moving forward?

Dr. Fox [indiscernible] avenue.

Yes. Do you mind to repeat the question? I had something going on at work.

No problem. Yes, Dr. Fox. I was just asking about the potential to use this and the appetite for different war front experiences given that the Ukraine trial experience -- the Ukraine experience, excuse me, was very much consistent with what was reported in Humacyte's clinical trial. And bearing in mind that at war, these patients don't necessarily have access to the level of medical care we do here in terms of going to hospitals.

Yes. Well, I think this product really meets the needs of a wartime injury because of the risk of infection, the need to have an off-the-shelf option and the lack of saphenous vein because of the slides that I demonstrated. Usually, the soft tissue injury is quite extensive. So that's very typical of war injuries. What they saw in Ukraine might have been more complicated by the fact that they didn't get evacuated quickly. But all of the injuries in wartime usually involve the extremities. There's usually a turn it get applied, and there's the need for an expeditious reconstruction right there in the battlefield. You can't fly the patient several hours to a different type of hospital. So really, I think the genesis of this technology could have existed -- could have been deeply rooted in the fact that wartime injuries needed another solution.

Our next question comes from Josh Jennings at TD Cowen.

All right. We really appreciate everyone spending time with us this morning. I was hoping to just follow-up on Dr. Lum's one of his answers, he's talking about the potential for ATEV to ultimately replace saphenous vein grafts. Those saphenous vein grafts are the gold standards in most clinical scenarios. But maybe you guys could review or one of you review just the complications durability of saphenous vein grafts. And do you all think that ultimately ATEV could become a move in front of saphenous vein grafts as standard of care for most of these vascular indications?

Yes. I -- let me clarify. I don't think I said that this is going to replace saphenous vein completely or 100%. I think that will take a lot of time to convince all the other vascular surgeons that ATEV is better than saphenous vein. I'm not saying that. I'm saying this may be in better selected cases, depending on the size of what you're trying to do implant into. I think this is a very good option. And it depends on the indication as well. So I think -- I don't think this is going to completely replace saphenous vein altogether, except in areas where you worry about size mismatch or infection, and you don't have been available. Yes, sorry. Can you say...

Yes, I apologize. I didn't mean to imply that you said that. I think you just you said that you didn't expect that upfront. But over time, maybe I was just reading too deeply into your answer that there's a potential for ATEV, again over time to replace saphenous vein grafts as well. But I guess really what I wanted to better understand is just the complications of saphenous vein grafts, I mean it is considered the gold standard, but how vulnerable is it to a product like ATEV over the next 5-plus years to be replaced as the standard of care?

I don't think it will be -- we will replace all saphenous vein graft as standard of care. I think where it may replace is prosthetic grafts. I think this is more a to replace prosthetic grafts than saphenous vein graft in general. And depending on what size, right now, there's only 6-millimeter size for Humacyte. But depending on what sizes come up in the future, I think the expandability and the length of the graft, can impact replacement for almost all the prosthetic grafts in the future, I think.

Great. And maybe, just to ask about -- I wanted to hear about the frequency of infected synthetic grafts in your practice because that seems like that is a near-term indication for ATEV and also iatrogenic injury, vascular injuries caused by and other procedures. How frequently are they? Any kind of ballpark in terms of the percentage of your vascular surgery interventions for those 2 indications where ATEV may be applicable.

I will address iatrogenic one since we enrolled about 5 or 6, I think, iatrogenic cases in the Humacyte trial. I think some of these were close calls. I think some of them we thought -- might be able to peel off the artery from the tumor, but then doing the operation, it became clear that the artery was just too plastic to the tumor. So we couldn't do it that way. So those were considering iatrogenic cases. But I think -- this -- as medicine gets more complicated, and we are pushing the frontiers of medicine and what we can do with surgery, I do think there's going to be more cases of vascular reconstruction in -- with tumor cases. So all these expanded iatrogenic cases, I think, are going to play a big role. The one other thing we've not really talked about in any of these slides is IV drug use. I'm not sure about the other states, but I'm sure Dr. Fox and Dr. Kundi can attest that in Baltimore, we are seeing a lot of patients injecting to the groins and also some groin blowouts and pseudoaneurysms and infected fields in the groins. Now, right now, we're just liking them. I used to be more aggressive about reconstructing in the past by being burned with infections and worse complications that can happen after that. So right now, we do a lot of ligation. At some point, some of these patients may need a reconstruction. And I think the ATEV is probably a good feel over here, either Iatrogenic injuries such as common femoral like a vast groin disasters from groin excess from endovascular procedures are also very prevalent. I think as we push the limits on also super cutaneous endovascular reconstructions for the heart and all sorts of stuff, we are seeing a lot of those groin -- iatrogenic groin injuries. In fact, 1 or 2 of our patients that we enrolled in the study were as a result of these massive aneurysms that develop from iatrogenic groin injuries. So I do think that there's definitely a role, probably increasing role, if anything, I don't think it's going to decrease if anything is going to be an increasing role for these iatrogenic injuries in the future.

I have the benefit of being able to do literature search as while this meeting is going on. And I can tell you that as for paper -- most recently, 2022, the rate of prosthetic groin infections for femoral popliteal bypass is between 2.5% and 5% over several different papers. And that is one of the most common, if not the most common lower extremity bypass revascularization is done worldwide. And in the presence of a prosthetic graft infection ATEV one would be the option rather than using prosthetic in the first case. And second, in the presence of an infected prosthetic bypass, ATEV would absolutely be the conduit of choice for reconstruction after infection.

Our next question comes from Vernon Bernardino at H.C. Wainright.

Laura, thank you for hosting this event. I greatly appreciate you providing the KOLs to the KOLs. Thank you running your insights in your case studies. Most of my questions were answered as far as -- and they were related to the sizes used available. So perhaps a follow-up question then is related to the iatrogenic uses. And in this case, with the code that is available likely to be available, how well could assuming additional sizes could be available, would the code be applicable available or for the reimbursement of ATEV in various sizes in other iatrogenic uses situations?

This is interesting. This is where my interest in coding overlaps. I don't think it would change things right now. I think there are 2 codes, right? If you talk thinking about provider or surgeon CPT codes, those codes are probably going to stay the same. I doubt that they're going to come out with a code, a procedural code for their change in billing because the amount of work that the surgeon needs to -- or time spent for the surgeon to implant a prostatic graft or Humacyte graft are same or very similar. So I don't think it would impact the physician reimbursement. But whether they expand the codes for hospital reimbursement that I don't know for sure.

Well, then I can pipe up with. So Humacyte has obtained from CMS new ICD-10 codes, which will, I think, become effective this fall. That describe using our vessel for arterial reconstruction, some codes are for upper extremity, and some are for lower extremities. So there are new ICD-10 codes coming.

Perfect. That's exactly what I wanted to know.

So I think we're going to have to wrap this up. This has been really a great session, and I'm so grateful to our surgeons, Dr. Lum and Dr. Kundi and Dr. Fox, for making time this morning during what I'm sure is a busy schedule. Humacyte values it, and I'm sure our analysts and our investors also really valued your time. And I also appreciate the analysts making time out of their day to attend this. So I think with this, we'll wrap up. And thank you, everyone, again. It's a great session.