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

Good morning, and welcome to the Humacyte KOL Event. [Operator Instructions] If you'd like to submit a question, you may do so by using the Q&A text box at the bottom of the webcast player or by e-mailing your questions to [email protected]. 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.

Hi. Welcome to Humacyte's webinar on the use of our HAV to treat war-wounded patients in the ongoing battles in Ukraine. My name is Laura Niklason, and I'm the founder and the CEO of Humacyte. And over the next hour, we're going to be presenting to you discussions from a number of surgeons who have used the HAV to treat war time and other types of civilian traumatic injuries. Essentially, this is going to be a key opinion leader discussion of their experiences using the HAV to treat vascular trauma in Ukraine during wartime, but also more broadly to discuss the problem of vascular trauma, both civilian and military. These are the standard disclaimers that Humacyte uses. We are a publicly-traded company. Amongst the key opinion leaders who will be participating in today's session include Dr. Shaprynskyi, who is a vascular and endovascular surgeon in Ukraine; Dr. Oleksandr Sokolov, who is a vascular surgeon and a phlebologist also in Ukraine; and also Dr. Oleksandr Stanko, who's a vascular surgeon and Head of Department of Vascular Surgery in Ukraine. In addition, providing some further background on wartime vascular injuries will be Dr. Charles Fox. Dr. Fox is a vascular and trauma surgeon working at the University of Maryland and at the Shock Trauma Hospital. He is also a retired U.S. Army Lieutenant Colonel and the former Program Director of Vascular Surgery training at the Walter Reed Army Medical Center. He's also a former 82nd Airborne Division paratrooper and a special forces medic. And so he speaks with first-hand knowledge of war injuries that were sustained by American personnel. But first, a little bit about the Human Acellular Vessel, or HAV. For those of you who may not be very familiar with the technology or the product. Essentially, Humacyte has been developing the Human Acellular Vessel or HAV, as an engineered human tissue that's grown essentially from scratch. It's grown from human cells in our bioreactors in our manufacturing facility. The HAV has been studied in clinical trials for the last decade and has been implanted into more than 500 patients. We studied the HAV in treating patients with kidney failure who require hemodialysis, in patients with severe peripheral arterial disease who have ischemia of their limbs and also in patients who suffered trauma, either civilian trauma in a Phase III trial that we're conducting in the U.S. currently or alternatively on a humanitarian basis in Ukraine, where we've used the HAV to help treat wounded soldiers and wounded patients in this conflict. What we've learned over the last decade of human clinical trial experience where we've accumulated more than a 1,000 patient years of exposure is that the HAV is durable. It's shows long-term durability and multiple indications and does not suffer mechanical breakdown. It acts as an excellent conduit for blood flow. And also, even though the HAV is engineered from human cells, it is decellularized and so it shows no evidence of immunogenicity in any of the clinical trials that we've conducted to date. However, as I'll show you in the next slide, the HAV becomes populated with cells from the patient after it's implanted. And we believe that this may provide this engineered human tissue -- human blood vessel with a resistance to infection, which makes it particularly useful in the treatment of patients with vascular trauma. Importantly, we make these vessels from a cell bank that we have here at the Humacyte facility. And these vessels have a shelf life after they're produced of 18 months. This means that we can produce human tissues, send them to hospitals and clinics, and they can be there waiting and ready when a trauma patient presents to the emergency room. As I mentioned earlier, the Human Acellular Vessel, or HAV, becomes repopulated with cells from the patient over time after it's been implanted. Humacyte has shown over multiple clinical studies that these cells when they repopulate the vessel become vascular type cells and really seem to turn the non-living HAV into a living functional artery over time. We believe that this important biological property really supplies the ability of the HAV to resist infection with bacteria but also provides the HAV with long-term durability over time and the ability to heal. In February of 2022, the Russian Federation invaded Ukraine. Beginning in March of 2022, just 1 month later, Humacyte began receiving requests from vascular and trauma surgeons in Ukraine, asking if they could have access to the HAV in order to treat some of the wounded patients who were suffering in this conflict. Humacyte takes this mission to save lives and [ wins ] very seriously. And so of course, we felt like we should step up to this challenge. And so Humacyte worked proactively with the international office at the Food and Drug Administration and also with the Ukrainian Ministry of Health to find mechanisms by which we could import the HAV from the United States into Ukraine and indeed bring it to 5 frontline hospitals that are near the conflict in that country. Again, the HAV is not yet approved by the FDA or by any other health authority. And so this is an investigational product that we brought into the Ukraine. The HAVs arrived at frontline hospitals beginning in June of this year. And since that time, we've treated a total of 10 patients with various types of wounds, including gunshot wounds, blast injuries, shrapnel injuries, et cetera. In some cases, we've treated patients who had previous repairs of their engineered arteries with another type of product, like a synthetic product or their own vein but those repairs failed and then the HAV was used to save life and limb later on in these patients. So that's the background of the humanitarian effort that we've begun this year in Ukraine and which remains ongoing. In the subsequent slides, we're first going to bring on Dr. Charles Fox, who's going to talk about his experience in treating patients who sustained severe wartime injuries and talk specifically about the types of challenges that are involved in treating severe vascular wounds. And with that, I'll hand it over to Dr. Fox.

Well, hello colleagues, my name is Charles Fox. I'm a vascular surgeon at the University of Maryland and work for the Shock Trauma Center. I have been asked to talk about vascular trauma. And just as an overview, I want to mention that vascular trauma is any injury to an artery, which carries blood to an extremity or an organ or to a vein, which returns blood to the heart and we typically categorize them as either blunt or penetrating mechanisms. In any event, an injury to an artery results in either hemorrhage or ischemia and in most cases, needs to be fixed. Well, anyone who's dealt with these problems knows that we have some unmet needs in the treatment of vascular trauma patients. For example, having it on-the-shelf, off-the-shelf option allows us to eliminate the time that's required to fall or prepare a conduit to fix an ischemic extremity. Additionally, these wounds are very prone to infection. And so the conduits that we choose need to resist infection particularly in combat trauma. Also, when we harvest the saphenous vein, these harvest sites can lead to complications and significant morbidities. They delay the ultimate restoration of flow because of the operative time that it takes to harvest the saphenous vein and the urgency by which the patient needs restored blood flow. Now I was stationed in the Army. During my final tour, I went to Afghanistan in 2010. And as you know, there were a significant number of fatalities and wounded individuals, and I was located in the Helmand province, very close to the battle area during a major operation. We were 30 minutes evacuation time from the forward edge of the battlefield and these were [ rickshaws ] that we used to move our patients from a landing strip into our emergency department. This is our resuscitation team, where we performed rapid sequence intubation and then move the patient on to either the operating room or the CT scanner. A typical casualty will have multiple extremity injuries as well chest or abdominal trauma and frequently we will be starting blood products and resuscitation efforts while the extremities are protected with tourniquets. We know that there is a rise of vascular injuries particularly in the extremities and is found in this most recently study to be about 5x higher in modern combat operations. This is probably a result of modern diagnostic imaging techniques and the advantages that we've seen with the application of tourniquets to stop bleeding. Military wounds offer a lot of unique challenges because they are deep and cavitary. They were laden with a lot of soil organisms making the wounds prone to infection. There are challenges with moving the patient through multiple echelons of care, and there are limitations to our ability to resuscitate and perform vascular reconstructions. Now we know the saphenous is a preferred conduit. That is because it is most resistant to infection, and it's also very durable with long-term patency demonstrated in short interposition grafts. We can use prosthetic grafts for wartime injuries but with some reluctance and acceptance that they are very likely to get infected or thrombosed. In civilian literature, there are some people who have championed the use of PTFE, but again, it's very likely that those grafts will have either limited durability or become contaminated. And this is why in wartime settings, there are a lot of bacteria in the soil, which gets imported into the soft tissues and sets up for wound complications. These require meticulous debridement and simultaneous reconstruction with conduit that is covered with healthy muscle tissue. Many times, the patients will have a traumatic amputation. In which case, if they have limited saphenous options, we may harvest the saphenous vein from an amputated limb but that requires transporting that limb with the patient and requires 2 surgical teams, 1 to control hemorrhage and one to dissect out the saphenous vein. Many times with these land mine injuries, our soldiers will have bilateral lower extremity injuries. This is a bilateral lower extremity popliteal artery injury where the saphenous vein was not suitable due to the diffuse fragmentation of the soft tissues. Now you can use prosthetic grafts with limited saphenous conduit, if you view it as a chunk of sorts where it's very likely to be removed and replaced. One option for performing a conduit that seems fairly resistant to infection is this Human Acellular Vessel. It's a 6 x 42 centimeter conduit. If you use bovine pericardium, it's got great tissue handling properties. It reminds me a lot of a bovine pericardial patch. It holds the suture very well. The needle tracks do not bleed very much, and it's a very soft conduit and easy to use. It's a regenerative product. It's a nice breakthrough in our technology because it comes as an off-the-shelf option. It's got an 18-month shelf life. As I mentioned, it's resistant to infection. It has no evidence of immunogenicity. The host cells repopulate into the HAV and as a principal investigator at one of the sites I have used it for both dialysis and trauma patients. It's been demonstrated to have long-term durability in ongoing studies. Now when I returned back from Afghanistan and left the military, I worked as a trauma surgeon in Denver and one late Friday night, a gunshot wound to the shoulder came in and the patient was stable. And therefore, IR was consulted because the patient had a possible [indiscernible] and a monophasic Doppler signal. The CTA showed that the left axillary artery did have some distal flow but was occluded and IR was not successful in performing an attempted covered stent after angiography. This is a view of the patient's posterior left shoulder with a bullet track and the CT scan with the arrow demonstrating an occluded left subclavian artery. The coronal slices of the CT shows the artifact that you can get from an embedded metallic fragment. There's a bullet at the clavicle, and there is distal flow into the left brachial artery, but not sufficient for limb viability. In reviewing the case before I took the patient to the OR for an open reconstruction with an HAV conduit. You could see that the left vertebral artery was intact but the left subclavian artery was occluded. There is some distal reconstitution just beyond the axilla. In this case, the patient had a large somewhat expanding hematoma. So this requires expeditious treatment, both to restore flow and reduce ischemic burden, but also to control hemorrhage. I chose an infraclavicular approach, dissected out the left subclavian artery. And this is a photograph taken from the patient's left side from the head, with the forceps touching the proximal left subclavian artery. The brachial plexus is just below posterior and deep to the resected part of the left subclavian artery. And then the final clamp is on the distal and at the left subclavian. Looking down the barrel of the artery, it's important to identify the intact non-injured adventitia so that the conduits do not thrombose because of a lack of inflow or because of occluded outflow. We passed [ Jet Line ], a [indiscernible] catheter, flush both ends with heparinized saline and then perform the anastomosis. In this case, we used the 6 millimeter HAV. We are careful not to clamp the HAV itself, but clamp the native artery and then this is the conduit with a nice ink surface anteriorly for orientation and sewing in the distal anastomosis. This is the final view of the conduit as it lies into the infraclavicular area of the thoracic outlet. The conduit is exceptionally good for extremities and torso injuries and the patient did well with the palpable pulse and had long-term follow-up. This is our surgical team in Afghanistan with me and my orthopedic colleagues, who did a lot of vascular reconstruction and we wish you well. Slava Ukrayini.

Thank you, Dr. Fox. And now it's my pleasure to introduce the first of our several colleagues from Ukraine. Dr. Oleksandr Sokolov, who is a distinguished vascular surgeon and phlebologist. Dr. Sokolov will highlight the most common vascular injuries that have been observed in this conflict and he will also review the typical treatment progression for these patients. Dr. Sokolov?

My name is Oleksandr Sokolov. I'm a Vascular surgeon from Dnipro, Ukraine. I have a little experience with HAV in Ukrainian conflict and I would like to tell about it. The most common vascular injuries observed in Ukraine are done with the most frequent cases of injuries that are caused by blast. So it's explosions, shrapnel or some elements of high-energy explosives. Also, I would like to tell that the most frequent body part that is injured is extremities. It's more than 84% of all vascular trauma. The most common places where we found the wounds of vessels are the femoral and [ dorsal ] veins and also the brachial vascular bundles. Other places are less frequent, but also can be found. I also want to tell that the classical and [indiscernible] evacuation way that is written in the TCCC Protocol of Evacuation in Ukraine was progressed. I think, and have alluded into the new one because our surgeons -- our war surgeons working with reconstructions and duplex ultrasound capability directly in the forward surgical teams. So as usually, we can found a lot of patients who already was reconstructed after they have wounded in the battlefield. They come to the hospitals and come to our step [indiscernible] to the city hospitals with reconstructions.

Thank you, Dr. Sokolov. Next, I'd like to welcome Dr. Vasyl Shaprynskyi, who is a distinguished vascular and endovascular surgeon as well as a phlebologist and a senior researcher. Dr. Shaprynskyi will review the first of several cases where the HAV was used in combat-related vascular injuries. Dr. Shaprynskyi?

My greetings from Kyiv, Ukraine, I'm Vasyl Shaprynskyi, vascular and endovascular surgeon, Ph.D. and Senior Researcher. Here are my case studies of patients treated with HAV in Ukraine. So from June to October, we performed 9 patient operations, with using Human Acellular Vessel. There were different kind of injuries and [indiscernible] shrapnel and black shrapnel injuries. All 9 treated patients in Ukraine have now reported the loss of primary patency and zero infections of the HAV despite contaminated wounds. So let me introduce to all cases . First one is 51 years old male with traumatic vascular injury from an industrial accident fall. He had bilateral injuries to the femoral artery and on preoperative CT angio scan, we checked that the superficial femoral artery on the thigh were injured. Because of phlebectomy performed on the left side 2 years ago and profundoplasty of the femoral artery profunda because of stenosis 2 years ago as well. We decided to use Human Acellular Vessel on the left side because of absent great saphenous vein and to put great saphenous vein on the right [indiscernible]. So using Human Acellular Vessel, we put the anastomosis in standard technique. This time anastomosis was put with parachute technique using 6.0 sutures -- suturing needle and proximal anastomosis was put using 5.0 suturing needle. In the follow-up, 1.5 months and 4 months, we checked that HAV has primary patency and we found no -- any evidence, no stenosis of the anastomosis, and flow and effusion in the legs treated with HAV and it was even better than that in limb treated with autologous saphenous vein, may be it depends on the 2-level injury on the right leg. The second patient is 55 years old male. We see a latrogenic injury of common femoral artery with thrombosis. It was post punctured pseudoaneurysm of the common femoral artery which was repaired with the HAV patch, size of the patch was 0.5 x 5 centimeters. Following the surgery, patency of the common femoral artery was confirmed and continued to remain patient at 1 month follow-up. And the last patient is an interesting patient, 37-year-old male with mine blast injury, femoral bone fracture and concomitant injury. On preoperative CT angiogram, we found pseudoaneurysm complication acute in both proximal and distal anastomoses of original arterial repair of the superficial femoral artery. After [indiscernible] antibacterial therapy of the bone repair, we decided to put Human Acellular Vessel in femoral to distal popliteal bypass position using HAV that is 6 [ centimeters ] by length. And in the follow-up, 1 month, we saw that HAV has primary patency and we found no aneurysm, no stenosis and different complications of the anastomosis. And to resume, I would like to say that in case of massive tissue infected defect, when there is no good vein or no time to look for good vein, the bypass due to prolonged ischemia, the HAV can be one of the best choice graft, which is quite compatible, immediately available and slow infection susceptible and [indiscernible]. And we're happy to have this opportunity to use the amazing graft, and we are happy to help our patients, which are going from our clinic on their both legs -- both limbs. Thank you for your kind attention.

Thank you, Dr. Shaprynskyi. And now we'll turn it back over to Dr. Sokolov again for his review of some additional cases from his personal experience with the HAV. Dr. Sokolov.

Saw some cases from our practice about patients who were treated with HAV. The first patient was a 26-year guy with a shrapnel injury of the left upper limb. It's a result of mine blast and imaging confirmed a metal fragment in the soft tissues. It was -- it has a size near 1 centimeter and the ballistic way of this shrapnel piece went through the vascular bundle. First, [indiscernible] was formed, and we saw that there was contrasting in veins. So we suspected the arteriovenous fistula and soft tissue injury. In the surgical operation, surgical [indiscernible] on the revision we found that the brachial artery was damaged. We have reconstructed it with the 7 centimeters piece of the Human Acellular Vessel. The vein was ligated. And the patient after it was ligated, was discharged without any complications. At 3 months follow-up, the patient is doing well and primary patency of HAV is great. And the functional limb was in full range. No any lack of sensitivity or movement. And also, we have found no signs of infection. Second patient came to us in August 2022. He was 2 years older -- 28 years old male with shrapnel injury of the right lower leg. We have found the [indiscernible] in the popliteal artery. We have done the repair with 5 centimeter HAV with prosthetics by end-to-end anastomoses. After 2 days, we confirmed good flow on HAV on the ultrasound. And the same was on the day 30 follow-up. HAV retains probable primary patency with no evidence of infection and with excellent limb perfusion. In September, we had a patient with more severe [ clinics ], 21-year old male with blast shrapnel injury of the left hip with damage of the vascular bundle, massive pulsating hematoma with clots and metal fragments. We repaired the superficial femoral artery with a piece of HAV near 7 centimeters. Once the patency of the HAV was confirmed and continued to remain patent with no evidence of infection at 1 month follow-up. In October, we have got the most severe soft tissue injury in a patient who came from the battlefield. 29-year-old male with multiple shrapnel injury. It was the left hip and we found that the vascular bundle in the area of inguinal ligament is [indiscernible] after the aneurysm on the CT scan it's presented, you can see it. Repair of the common femoral artery was performed using the end-to-end anastomosis with [indiscernible] On the day patents -- on the day 10 patency of Human Acellular Vessel was confirmed and continued to remain patent with no evidence of infection at 50 seconds day of the follow-up. So you can see the confirmation on ultrasound directly right now. So thank you very much.

And finally, our last speaker will be Dr. Oleksandr Stanko, a distinguished vascular surgeon and the head of his Department of Vascular Surgery. Dr. Stanko will review additional cases that highlights his experience with the HAV in Ukraine.

Dear colleagues. I would like to share with you our experience of treating of 2 patients with injuries of arteries of the limbs, both of them are the soldiers of Ukrainian Army, who were wounded on the battlefield. So our first patient is 42 years old male who was shot with [indiscernible] caliber 545 automatic rifle. He was previously operated in our clinic where the injury of superficial femoral artery was diagnosed. And doctors used [indiscernible] muted graft to replace this [indiscernible] defect femoral artery. Next day, the thrombosis of this [indiscernible] graft occurred and there were signs of infection. So these patients was transferred to our clinic. Urgently, we made the revision and debridement of the wound, removed the this thrombosed and infected graft and used about 25 centimeters long HAV conducted in medial part of rectus femoris muscle and we have made 2 made to end-to-end anastomoses. Both of anastomoses were covered with muscles. The duration of ischemia of the leg [indiscernible] was about 15 hours. So in postoperative period developed the necrosis of part of muscles of the shin. In postoperative period, we used the negative wound pressure devices for treating the wound of the hip. Nevertheless, in the 4 months follow-up, the patency of HAV was confirmed on Duplex Ultrasound and the geography with good blood velocities in femoral artery, popliteal artery, and tibial arteries. And there were no signs of infection of HAV. Our next patient is 32 years old male with shrapnel wounds on both legs in the hospital near the battlefield. The injury of left popliteal artery was diagnosed. And they used the primary suturing of the popliteal artery. Patient was transferred to our clinic. In 2 hours after the patient admitted to our hospital, the massive bleeding from postoperative wound began. We made the revision of this wound, resected the injured part of popliteal artery and replaced it with autologous great saphenous vein. Three days after, unfortunately, the massive bleeding from postoperative wound relapsed. Due to infection and infection destroying both anastomoses between arterial and popliteal artery. We tried to make the general reconstruction using the great saphenous vein from the hip. But as you can see on the second picture, it was very close. So we performed the femoral distal popliteal repair using HAV about 28 centimeters long. Subsequent skin grafting was performed to close the wounds on this leg. At 3 months follow-up, the HAV retains with primary patency with good blood [indiscernible] velocities in popliteal and tibial artery and we observed no signs of infection of infection of HAV. In conclusion, discussing these are our 2 cases, I would like to stress on the point that both of these HAVs were working in very hard and maybe tough condition and we had now such option like HAV. I guess there were no chances to save the limbs or even lives of our patients. For us, it was just like a miracle. Thank you for your attention.

Thank you, Dr. Stanko and to all of our guest speakers today. We can only express our sincere gratitude for your participation in today's program, and also, more importantly, for the care of these terribly wounded patients, both in the Ukraine and also in the Middle East. We're very grateful for your work and for your service. Before we begin our question-and-answer session, I want to spend a few minutes discussing the role of these results that we are obtaining in Ukraine in real-world war injury settings and how they relate to our planned Biologics Licensing Application or BLA filing, that we plan to do with the FDA next year. What we believe we're seeing from the results in Ukraine, as was described by the surgeons in this session is that the HAV has been vital for providing blood flow and restoration of function to injured limbs in multiple Ukrainian patients. This restoration of blood supply has allowed all of these patients to avoid amputation and we've also seen zero infectious complications from the HAV implants despite being implanted into very contaminated settings. The Ukraine experience, therefore, represents genuine real-world experience in a fairly -- in an area that is fairly constrained for resources and might be considered an [indiscernible] environment. The severity and the heterogeneity of these injuries really complements the ongoing civilian trial that we're doing in vascular trauma in the United States, which we refer to as the V-005 Clinical Trial. Importantly, as I mentioned earlier in this program, Several of the patients who we've treated in Ukraine actually received the HAV for limb salvage after prior attempts at fixing their arteries have failed. Two patients had failed saphenous vein grafts, and one patient had a failed and infected graft made out of a synthetic material called Teflon. So it's important to note that these are all patients who might very well have faced limb loss because the first attempt at salvaging their vasculature failed, but the HAV was able to restore blood flow and allow these patients to retain life and limb. So again, we're very grateful for the work that's been done in Ukraine by these caregivers. And I'm also quite frankly, very grateful to all of the people at Humacyte who've managed to make this possible. And with that, I'd like to turn it over to the audience for questions and answers.

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

All right. Great. Appreciate the case studies and everything you guys are doing there. I guess I'm wondering for the surgeons from Ukraine, just given the variation of the injury site, which arteries or veins do you believe that the HAV is best suited for as you think about the 10 patients that have been treated, where do you find the best utility based on the site of injury?

Dr. Stanko, would you like to answer that?

I guess, the best arteries to repair with HAV is arteries for the moment are the limbs. It may be very [indiscernible] quick and with the diameters of arteries between 6 millimeters and maybe 4 or even 3 millimeters. I guess it would be also possible to repair the tibial arteries with HAVs, but we have no experience on this.

Any other comments from our Ukrainian colleagues?

Well, thank you very much. My name is Oleksandr Sokolov. Hello, everybody. About site of [indiscernible] recommendation, I can comment that the best places are brachial arteries and femoral arteries due to diameter of the graft. I think in future, there will be the graft with diameter less than 5 millimeters or 4 millimeters. It can be possible to work with the tibial arteries. But in this case, the limb salvation is not so critical as to end the brachial or femoral artery is damaged. As for iliac segment, I can say that the HAV can be used as part of something like patches to make from it to subtotal implantation or [indiscernible] recovery. That's all. I think it's correct for today's base. Thank you.

And then just my other follow-up is, as we think about the follow-up, patients so far 3 months postoperatively appear to be doing well. Are you expecting or concerned at all about longer-term follow-up? And kind of how do you think about what may arise from the HAV in these patients as we think about long-term care?

That's a great question. I think -- as for a long-term follow-ups and for data gathering now on Ukraine, we have a lack of opportunities for it. But for the cases that we have reported already, from my personal opinion, it's not so easy, but it's possible. We gathered the data more than 3 months. And I see that it's due to our friendship of colleagues in Ukraine. So we are meeting with the doctors from other cities, and they can help us to get access to patients. And now we see, and we are sure that we can do it, that we can find the patients in the cities in the more than half of the cases. It's a large percent. And due to higher education level of Ukrainian Vascular Surgeons, they are using the ultrasounds and most of them has an access to our ultrasound equipment. And for sure, we can gather that. About patients that got already 3 months follow-up and procedures of the post-operational steps, I can say that we have 100 persons of working implants and we have 100% of [indiscernible] with high risk of infection. And also it's as Dr. Shaprynskyi said in his presentation, it's our common opinion, that we are saving time in surgical [indiscernible] when we don't gather the vein for making a graft. It's very, very significant for patients in critical status. As for the survival and for limb salvage [indiscernible] too. So I think everything is possible. Thank you very much.

Our next question comes from Bruce Jackson from Benchmark.

A question for a panel of surgeons. The data speak for themselves. It's really excellent. If the HAV were approved for use and readily available and you were presented with the choice of whether to do a harvest of a vessel or use the HAV, which one would you choose?

So I can continue if it's possible. So thank you for your question. For sure, the classic surgical way is vein grafting. It's classical and it's recommended in all of the evident-based recommendations with vascular surgeons of the world. And I can say that it's really significant because if we have time, if we have a patient resource, his health [indiscernible] source to provide the classic operation for sure, it will be cheaper, it will be more classical way. But for the patients with trauma, they have not only the punctured points injuries. For the patients who got the wounds in war, mine blast injury has a lots of sutures not on the fragments of ballistic way. It's a tissue contusion. It's not [indiscernible] directional ballistic way. For sure, it's a contaminant damage of soft tissues, nerves and also the saphenous vein that is damaged in the most of the cases. It is very frequent, but we should say that the saphenous vein as Dr. Stanko said in his presentation can be varicose and has varicosities, it can be damaged with chronic renal disease. That's why it's not -- we cannot get a diagnostic imaging directly before the surgical operation in 100% of cases. That's why the HAV, it can [indiscernible] , it can be varicose changing. It kind of has varicose changing. And also, it's proof leak and it can repair itself. It is -- we have an evidence in the trials in the [indiscernible] fistulas that were made before this event, yes. That's why I think that the HAV has a lot of [indiscernible] due to vein harvesting and significant and relevant infectious protection. So it's very nice features for it. That's why when we see that the patient is young, and have a nice saphenous veins, it's not in spasm, and we can for sure use it, but HAV get a lot of [indiscernible] classes. Thank you very much. I think Dr. Shaprynskyi will continue in this case.

/> Hello, everybody. Excuse me, maybe I will be interrupted because of poor Internet. I totally agree with Dr. Sokolov, and I would like to say that if you would have the opportunity to use HAV as a tissue graft in the future. I think that, in my opinion, I will use it HAV at once, if I have this choice. If we do have another diameters of this HAV graft, it will be more better and more suitable in different localizations of the lesions. That's why I think that bioengineering graft is the future, and there is no need to use great saphenous vein or others to use to waste time and because we will have the best choice graft. If I completely understand the question because of interruption.

Just want to add about a few words. If we are talking about atherosclerosis and occlusions, maybe I would prefer the great saphenous vein and autologous vein. But if we are talking about injury and trauma, at this moment, I would prefer HAV because it has a stable diameter. It has -- we don't need the previous diagnostic for finding the vein or looking for it and makes the time of ischemia much shorter. We don't lose our time to harvest to the vein. And if we're are talking about injuries it's a very important point.

So our next question comes from Matt O'Brien from Piper and I'm going to read them out loud. So his first question is, are there any limitations to the HAV in terms of the types of patients you can treat? And do you need larger HAVs in the future?

I just think that HAV is the future, and we will not -- I don't know what future we are talking, but I almost certain that we will not use in future any other grafts, but some kind of HAV or something like that. It's very comfortable to work with it. It's fast and it's predictable for now. And I guess it would be better in the future, much better than now, okay.

And for big diameters like aorta and as I had in the first question, we need a bigger diameter HAV. And I would like to add for the first question that in my personal practice in the case of infected aorta and we have no adaptive vein to this segment, I use great saphenous vein preparing for the adoptive diameter. I use the great saphenous like cutting it longitudinal and by spiral suturing making with adaptive diameter. That's why I would like to say that even this diameter HAV 6.5, we can use in preparing to the big diameter using this technique of serpentine suturing preparing a big diameter. So if we will have this in the future, a big diameter, we will not wasting time to do these diameter by handmade with saphenous vein. I hope you understand. Thank you.

Sure. So from my opinion, every segment of surgical technique has its own place. And I think the HAV will have the strong and one of the first places in future of all the vascular surgery. As Dr. Stanko said before, for sure, we should adapt to it as a society, but I think it will be the fast process because it's really very comfortable. And for sure, the selection of the graft, [ Dacron ] graft, PTFE graft, vein graft has that significant courses. That's why this bioengineering product can be the choice of selection and the point of view in all the vascular surgery in the world. I think everyone will be happy to work with it. Thank you.

Great. So his next question is what is the longest you have a patient out to at this point, for example, 3 months, 6 months, et cetera.

So I can answer. So our first patients have came in the summer, and we have follow up near 5 months so already [indiscernible] will be completed for this success result. And 4 of these [indiscernible], the most part of the significant complications are already passed in the general practice of the vascular surgeon. So we have some [indiscernible] thromboses, aneurysm that can be found, any kind of anastomotic interruptions at all. That's why after a half of year where I can certainly say that yes, for sure, it works. And it's not worse than the vein, it's not worse than the [indiscernible] former tissue graft for now. And we continue to observe the patients to investigate their adverse events there because it's a point of interest for assets in specific for investigators. But now the new cases are coming at the Russian aggression is still not stopped for PT. We are waiting for victory. But our point is right here, and we are continuing to work with wounded soldiers. Thank you.

Our first patient visits us unexpectedly last week, and it was a 6-month follow-up. And there were no evidences of complications of HAV, no evidence of infection, or thrombosis. We made the duplex ultrasound and I don't think it was good to me. So it's the longest case for follow-up for now.

And for me, the longest case is 4.5 months. And as well. The results are quite good because of absence of aneurysm, hematomas, infection, and so. Thank you.

Great. And one last question from Matt. If there is a problem with the HAV, how difficult is a revision procedure? And what might you be able to do for the patient.

What do you mean of the revision procedure for HAV?

I think revision is -- revision procedure is the same as for any vascular trauma. It's similar. We have some issues when we are working -- I'm trained because it has some type of difference in its structure. It's different from the vein. It's different from the PTFE graft. That's why I think the opportunity with vascular training [indiscernible] it's the point for everyone. But I think the 1 or 2 anastomoses in the laboratory, it's enough because all other parts of surgical intervention is similar. As I understand your question if it's correct. Yes?

I do think I'd like to jump in here just for a minute to address Matt O'Brien's question a little bit. I do think the Ukrainian surgeons may be at a bit of a disadvantage because I'm not sure there have been any reinterventions on the HAV that have been implanted. Certainly, we have re-interventions on HAVs in the U.S. from some of our other trials. But I think for these 3 practitioners, I'm not sure they've had to reintervene yet. But from -- speaking with other surgeons, they all report that reintervention on the HAV is exactly as they would do with other types of bypass. So there's nothing special about it.

Great. Anything else, Dr. Stanko?

We have no experience of reinterventions with HAV. So I can add nothing.

Okay. Great. So this concludes our question-and-answer session. I'll now turn it back over to Laura for closing remarks.

Well, again, I just want to express my sincere thanks for everyone who's participated this morning or this afternoon as it is in Ukraine. I know, obviously, our surgeons are very busy. And again, we really appreciate you taking the time and sharing your experiences with us. Humacyte's HAVs has been used across Europe and in Israel and across the United States. So we're really developing a global experience. And we hope to move forward with gaining U.S. and then international approval for using the HAV to treat traumatically injured patients. So again, thank you for your time. This was a great session.