SHAHBAZ MALIK: Thanks, Kim, for that lovely introduction. And thank you all for making the time to come here today in person and those who are joining us on the Webex. I have quite a few slides. So this might be a little bit quick. If there is any burning questions, please interrupt me. But there should be time for some questions at the end.

So I'm tasked today to talk about chimeric antigen receptor T cells. It's an exciting area of recent advancement within the field of oncology and immunology. And so we'll talk today about the background toxicities and efficacy of this new therapy.

I have one disclosure. Last year, I was invited to an advisory committee for Kite, which has one of the commercial products. And I received an honoraria for that.

Just a shameless plug for our medical center and for our program-- I work at St. David's South Austin Medical Center. The program was promulgated in 2014 in February. I had Dr. [INAUDIBLE] joined later that year. And it was started by physicians from San Antonio. We became FACT-accredited quite early on for autologous stem cell transplant. We became allogeneic FACT-accredited, and immune effector cell therapy-accredited last year. And our volumes have picked up considerably over the past several years.

We are part of a larger group, the Sarah Cannon Blood Cancer Network. You can see all the locations here and overseas. So this is our umbrella organization. And they've helped us implement standardized protocols across our network to ensure quality control and ensure our patients receive quality care throughout the HCA and Sarah Cannon Blood Cancer Network.

Our facility in Austin or in South Austin comprises of eight dedicated BMT beds behind double-locked doors. It's HEPA-filtered, and our whole floor has 24 beds. We're planning on expanding the sixth floor. And hopefully, we'll pick up some more beds as our volumes have picked up considerably.

We also have a clinic on the first floor that's very easy for us to go and see our patients and for them to come into our unit from downstairs if they need to be admitted. It's just five flights or a short elevator ride up or down. And we're expanding that later this year. Hopefully, we'll have occupancy with expanded capabilities in October.

As you can see, our volumes have picked up over the past several years since the program started. This is updated as of April 30 of this year. May and June are going to be pretty-- or May has been, and so far in June, going forward are going to be quite busy months. We're projecting about 50 transplants by the end of June, so on pace for about 100 transplants this year while we did around 67 last year.

Our local immune effector cell therapy committee, which is important for these CAR-T cells, as you'll see later, because they have unique toxicities. I met for the first time in preparation for this new therapy in September of 2017. The committee consists of transplant physicians at South Austin Medical Center, myself and Dr. [INAUDIBLE] and my partner, local oncologists.

And if there are any oncologists up here that want to join us for our meetings, we'd be happy to have you all. Pulmonology, critical care, ER, hospitalists, neurology, infectious disease, and cardiology, that we all have representatives and champions in those fields, are working with us on this important therapy as well.

In those meetings, we discuss and implement protocols surrounding CAR-T cell therapy, order sets, standards of care. And we will also, when we have the therapy available, discuss incoming patients as these therapies become available locally.

So our objectives today are five-fold-- to establish the landscape of cellular immunotherapy, identify current indications for CAR-T cell therapy, summarize toxicities, define the term "cytokine release syndrome," and describe options for treatment of cytokine release syndrome and its close cousin, CAR-related encephalopathy syndrome, or more simply, neurotoxicity associated with this therapy.

So despite the advances in the past few decades, there's still much to be accomplished, without being said, for cancer care. This talk will focus specifically on hematologic malignancies, more specifically ALL and aggressive B-cell lymphomas. While many patients respond, the patients who relapse after first line therapy-- they have pretty dismal outcomes in general. And we'll go over specific numbers for that. CAR-T cells are an exciting new therapeutic option that we'll talk about further as this talk goes along.

So immunotherapy really got its start back in the 1890s with Dr. William Coley up in New York City in an institution that would eventually become Memorial Sloan Kettering Cancer Center. He had a young patient who had osteosarcoma who died of the disease pretty quickly. He was a surgeon, and he attempted to amputate further and further up. He combed the literature and found that a patient had erysipelas, or a skin infection-- went into a spontaneous remission.

So he took the bacteria that causes this and injected into many patients. Several patients, it worked. For most, it did not. And it went by the wayside. As radiation therapy became something that was feasible and more-- how should I say this-- more predictable. That became something that was standard of care. And this immunotherapy went by the wayside.

Got picked up again up in the mid-1900s where an autologous stem cell transplant came into being, and allogeneic stem cell transplant came into being. We were able to put patients, who otherwise would be insensitive to chemotherapy and radiation, into remission using donor stem cells. And even further than that, patients who even relapsed after allogeneic stem cell transplant-- be able to rescue them with donor lymphocyte infusions.

So as the century went on, we discovered more and more the importance of the immune system in regulating homeostasis and preventing cancer and also for eradicating it. The rituximab era, the antibody era, came into being in the late 1990s. And it brings us over the past 15 to 20 years into CAR-T cells.

You know, the efforts initially for CAR-T cells were stifled by lack of funding. The NIH had multiple grants written for them from various groups, most notably from the UPenn group. And they were rejected multiple times. There was private funding that was of approximately $1 million given to them by the Alliance for Cancer Gene Cell Therapy to fund their work.

They had initially treated three patients with that $1 million. And two out of the three patients who had CLL achieved a CR. As funding ran out, they published these findings as case reports. And that brings us to August 25, 2011. These reports piqued the interest of the medical community at large as they were published in The New England Journal of Medicine and other prominent journals and allowed for further funding from the NIH.

This patient was the first CAR-T cell patient, Emily Whitehead, who was treated at UPenn with the new NIH funding. And this video is pretty illustrative and pretty heart wrenching-and dramatic. So I'll show it to you. It's about six minutes long.

[VIDEO PLAYBACK]

- She relapsed in October 2011. And at that point, we know it wasn't kind of the standard garden-variety leukemia. Then she relapsed again in February 2012. And so it was at that point that we made the decision that we needed to go somewhere else where-- we really needed to try something new and something different.

- We were told that we were down to 48 hours on making a decision, or she could start to have organ failure.

- We knew that there were things offered here that would be different from what a local hospital could offer, and things that were more, I guess, cutting-edge, newer things were being tried that weren't being tried anywhere else.

- So we're really down to the CART-19 as what's left for Emily to cure her. So we're ready to go today.

- Right now, we're feeling hopeful, really hopeful. It's a little bit scary because Emily is one of the first patients to receive this. She's the first pediatric patient.

- I felt all along that she's going to beat cancer. And today's our day when we're going to start doing it. You want to say anything else, huh? What are we going to do today? What are we going to do today? You going to get your T cells?

- Mhm.

- What are they going to do?

- Do you remember?

- Mm-mm.

- Mm-mm.

- What are they going to take away?

- The cancer.

- Cancer. That's right.

- So CART-19 is a treatment for patients with fairly advanced leukemia. Most patients who have the kind of leukemia that CART-19, treats which is the most common kind of childhood leukemia-- it's called B-cell ALL. That is a disease where most patients are treated very successfully with standard chemotherapy.

But there's a subset of those patients and a substantial number of children in the United States for whom chemotherapy does not work, or it works temporarily. So for that group of patients who have very treatment-resistant disease, we need something brand new. And CART-19 is for those patients.

The essential nature of the CART-19 treatment is that we have to get cells from the patient. These cells are called T cells. They're cells in the immune system that need to be engineered. And we can engineer these cells to go after cancer cells and kill them.

[MUSIC PLAYING]

- So Emily had her-- the CART-19 therapy April 17. And we were told to expect that she would possibly get a little bit of a fever and feel like she had the flu. But she ended up getting pretty sick shortly after. And she was put on a ventilator because of how sick she was.

- They had come with a team of doctors in the PICU every morning and did rounds with us. And we were always first. And they would come to us and kind of show us a line on the floor and say, if that's the line of survival, Emily has almost stepped past it.

- During the few days when she was quite sick, she was receiving the most advanced medical care that's available on the planet. So the people in the hospital were taking care of this child during the period she was quite sick until such time as we learned what was wrong, had a chance to intervene, and made her better.

One of the results of her T cells growing in her body was that she had an increase in various proteins that control the immune reaction. And this increase in those proteins were actually making her ill. We actually found that one of these proteins was quite elevated. And as it turns out, there's a drug that targets that exact protein. We gave her that drug, and she had a dramatic response. The ICU doctor on that night told me that he had never seen a patient that sick get better that quickly.

- We weren't sure at that time if the CART-19 cells were working, if they weren't working.

- About three weeks after we gave her her T cells, we did another bone marrow test. This young lady had not been in a remission for a number of months. And she now was in a complete remission. So she completely responded to our T cell therapy.

[MUSIC PLAYING]

- We were able to go home June 1. And since that time, she's been great. She's been happy and healthy and returned back to school in the fall. We know CART-19 was really the only option left for Emily. And although we weren't sure how it's going to work because she was the first child, we still felt like by enrolling her in the trial, even if it didn't work, it would give them a little bit more information.

And from that, hopefully, they would learn something and be able to help other children. You know, but we entered her into the trial really hopeful. She's extremely smart. She's very creative. She's funny. She makes us laugh all the time. I mean, she never complains.

- She told us from the beginning that she would continue to fight and do what we ask as long as we were there with her. So we've both been there through this entire fight, all three of us together. And we just stick together as a team. And she's definitely our hero.

- And we checked her bone marrow for the possibility of disease at two points. We checked her three months and now six months out from the treatment. She has no disease whatsoever. We need to treat a larger number of patients before we understand what the success rate might actually be. Seems like the cells stick around for a long time. That actually might provide long-term disease control.

That is, of course, the most exciting potential part. But we need more time to know if that's actually where we are. To see her go from leaving the hospital and starting to recover, to basically going to school and playing soccer and looking like every other kid is just wonderful. I think the best thing about doing what I do.

[END PLAYBACK]

SHAHBAZ MALIK: OK, so CAR-T cell therapy is currently approved in the US. The first approval-- OK, so CAR-T cell therapy is currently approved in the US. The first approval occurred back in August of 2017, I believe August 30, and was approved for ALL based on the trial that Emily was a part of.

So they treated patients up to the age of 25 with B-cell precursor acute lymphoblastic leukemia. And the indication on the FDA labels that the disease has to be refractory in second or later line-- refractory or in second or third line therapy or further.

The other indication which came later in the late fall was another drug called axicabtagene-- these are pretty bad tongue twisters, both of these medications-- that a trial was published in The New England Journal Medicine. We'll go over it later in 2017. But the trial was reported in multiple meetings. And this prompted the FDA to approve it in diffuse large B-cell lymphoma and other aggressive B-cell lymphomas that you can see listed here.

So how does CAR-T cell therapy work? It harnesses the power of cytotoxic T cells to recognize a target cell, in this case, a tumor cell. And it either released enzymes like granzyme B and perforin to poke holes in the cell and also to attach to proteins which allow the cell to undergo apoptosis.

The CAR19 T cells are quite active and cause a multiple-fold increase in multiple inflammatory cytokines, as you can see here, interferon gamma, TNF alpha. Increases in IL-10 granzyme B also occur. This is just illustrative.

The CAR-T construct-- and this is what made this therapy go forward in the early 2000s, were the second-generation CAR-T cells. The first generations were actually made by an Israeli scientist in the early to mid-1990s. It was first reported in 1993.

Problem with the first-generation CAR-T cells is that they are constructed of multiple parts. But the most important part-- it came to be-- well, they're all important. But the most important part for persistence and continued stimulation of the CAR-T cells were the costimulatory domains. There was a CD3 zeta domain that was intracellular.

And within these T cells that allowed signaling, to allow them to kill the target cell-- these cells pooped out pretty quickly. They could recognize a few cells, and then they would stop, which was not good for eradicating a cancer that was ravaging somebody's body.

So the innovation of the UPenn team was to add a costimulatory domain. They used a costimulatory domain called 4-1BB. And the one that was used for lymphoma by the other group-- that was the NCI group-- used a costimulatory domain called CD28. It's not really important to know, but there are slightly different approaches for this.

The CD28 costimulatory domain is associated with rapid effector function. But the 4-1BB domain is-- we think that it enriches for central memory T cells that allow for continued surveillance. The treatment for diffuse large B-cell lymphoma for which the CD28 domain is approved for is relatively short, a couple of months of therapy.

So for diffuse large B-cell lymphoma, R-CHOP times six works. And the disease goes into remission. But for something like ALL, the treatment last years, two, three years. And a short-lived, short-acting CAR-T cell therapy would not be very active for something that needs constant surveillance against for a number of years.

So the group at UPenn decided to use the 4-1BB domain. As it is right now-- and we'll talk about this a little bit later-- the 4-1BB domain CAR-T cell is also approved for non-Hodgkin lymphoma. that approval came in about a month ago.

This is just an illustration of what I talked about in the previous slide. The CD28 CAR-T replicates pretty quickly and then goes away. There are some patients where it persists, but this is the typical way or the typical curve that these CAR-T cells take. In the 4-1BB domain, they persist for years. Emily's cells, even six years later, are detectable in her blood.

So the manufacturing process that Dr. Grupp talked about in the video involves a process called apheresis, which is what transplant centers do all the time for every patient that needs a transplant. We either apherese from the patient for an autologous transplant or from a donor for an allogeneic transplant.

So we collect mononuclear cells. We activate the T cells. We express the CAR via viral vector, either a lentivirus or a retrovirus vector. We expand the cells. We test them and freeze them. And we reinfuse them.

This process takes anywhere from 18 to 25 days, depending on what manufacturing process is used. Now, there's companies that are trying to make this faster and claim they can, but we won't get into that. There's companies trying to do this in two days or three days because these patients, as you can imagine, are very sick.

So just to get into what Dr. Grupp touched on in the video, pediatric ALL is one of the success stories in the past couple of decades of cancer therapy in general. 80% to 90% of patients in the pediatric setting are cured with first line therapy. However, when it comes back, that's quite bad. The overall survival rate for children who have relapsed refractory disease, the minority of patients overall-- their survival at five years is about 20%.

For adults, it's even worse, about 10%. The median overall survival, even for adults who undergo allogeneic transplant, who get to that point, is 9.3 months. So even allogeneic transplant is not that good for patients who have refractory disease and go into transplant with refractory disease. If you can get him into an MRD negative state, that's good. But that's a topic for another time.

The prognosis-- this is just curves to show you in a pictorial way the survival curves, and they're pretty dismal for these patients. And just remember these when you compare them to the slides that I'm about to show you for survival curves.

This article was published in 2018 and can be pulled up on NEJM. This is the 4-1BB CAR that Emily got at UPenn. It's called tisagenlecleucel. It's a tongue twister. I don't know if I'm allowed to say brand names, so I won't say it. You can look it up. It's much easier to say the brand name.

In this trial, 107 patients were screened, 92 were enrolled, and 75 underwent infusions. So about a quarter of patients or slightly more than that dropped out for whatever reason. Some patients progressed. There was a lot of patients who have progressed and died, and patients who went on to undergo other clinical trials as well.

This is a single arm, phase 2, single-cohort study with 25 patients. It was a global study. There was sites in the US and sites overseas. The CR and CRi rate at three months was 81%. There are patients who lost their response later on in the overall survival curves. You can see an event-free survival curve that you can see, so between 40% and 50%. We can say with some confidence may be cured, as late relapses and ALL are pretty uncommon. They tend to relapse within the first few years after they go into remission.

CRS, which we'll talk about a little bit later, but it's easy to talk about now because we're talking about this trial, occurred in 77% of patients. The median time to onset was three days, which is a little bit shorter, which you'll see late-- or a little bit longer than the CD28 CAR-T cells. 47% of patients were admitted to the ICU. And on average, they stayed a week.

25% of patients needed vasopressors. 44% needed oxygen. 13% needed to be put on a vent. 37% of patients received tocilizumab, which was the drug that they gave to Emily to reverse her condition. And about a quarter received corticosteroids.

The neurologic toxicities occurred in about 40% of patients. The good thing about this trial is 0% of patients had grade 4 or above events. Any questions on the ALL trial that are burning right now? OK, well, I'll go on to the next topic.

Refractory diffuse large B-cell lymphoma patients-- you can see there's a theme here. If it's recurrent and refractory, it has a really bad outcome. If they're primary refractory, the overall survival at two years is 24%. And if they relapse post auto, their overall survival is about 20% as well. This was a schol-- it's something called a scholar study where they looked retrospectively at this data. This is not a prospective study.

Axicabtagene ciloleucel was approved by the Food and Drug Administration last fall for non-Hodgkin lymphoma based on this study, which was also published in The New England Journal of Medicine. As you can see, these trials are very small. The trial accrued 101 patients who were actually treated with the medicine, axi-cel.

There was also a phase II trial. The overall response rate was 82%. The CR rate was 54%. And the survival at 18 months was 52%. So the curve flattened out pretty well at around a year and 1/4.

If you went into a complete remission, you did well. So at three months, if they evaluated you via PET/CT scan or CT scan, and you were in complete remission, you tended to do very well. So comparing two patients who relapsed, and their survival was 20%, if you went into a CR, your long-term survival in this case was closer to 70%, which is remarkable.

Partial responses didn't do too well. There are some patients who went on to allogeneic stem cell transplant but unfortunately, a good number of those patients died as well. In these two trials, very few patients overall went into allogeneic transplant. It was in the single digits for both trials.

But if you got a partial response, you were in trouble. These patients didn't survive very long in general and went on to-- some patients were able to receive a second dose of CAR. But they were only able to receive that after the three-month mark. And in most cases, it didn't do anything.

CRS occurred in more of these patients. This is the CD28 costimulatory domain CAR-T cell. CRS occurred in 93% of patients. The median time to onset was faster. So you can go back to in your memory banks to that graph that I showed you, that these patients-- their T cells multiplied more quickly and more dramatically.

The median time to onset was two days, and duration was eight days. ICU stay wasn't reported, but in my experience, a number of patients went to the ICU. We ran this trial at Stanford.

I was involved, actually. I took care of the first patient. And that was dosed at Stanford. He did not go to the ICU, but got neurotoxicity and needed tocilizumab. He went into a partial response and unfortunately passed away several months later. There were several other patients that I was involved in the care of, about a half dozen. About half of those patients went to the ICU.

So 17% of patients on this trial needed vasopressors. Almost half received tocilizumab, and a 1/4, again, received corticosteroids. Neurotoxicity occurred in a little bit more of these patients. And 28% of these patients had grade 3 or above neurotoxicity.

In this trial, one patient died of pulmonary embolism. One died of HLH macrophage activating syndrome. And the oncologist here know what that is. But the patient was discharged from the hospital after about a week and came back to the hospital with high fevers and ended up dying on this study as well.

There was one cardiac arrest associated with cerebral edema. The patient that this happened in was at Stanford after I left, a young man in his, I believe, late 20s, early 30s, who actually died from cerebral edema, which they weren't able to reverse.

CAR-T cells aren't approved for primary CNS lymphoma. But this is a illustrative example of this medication even-- or this drug or living drug, where it can even have responses within the CNS. And you can see that these CAR-T cells were made against CD19.

So this was reported in The New England Journal as a case report in 2017. And you can see the hot spots here and here. There was a subcutaneous lesion and a lesion within the parenchyma of the brain that you can see on PET/CT and also MRI.

The patient went into remission. However, they had a subcutaneous relapse. This was biopsied. And with the biopsy, there was enough inflammation there for it to go into a spontaneous remission again. So this patient actually went into remission just when they made a little incision and took out a biopsy piece. So I believe this patient continued to be in a CR. But it's pretty remarkable that these cells stick around and are able to traffic in areas where you have an insult.

The toxicities can be global. This cartoon just shows that. It's, I think, pretty hard to read. But you can see the arrows pointing to every single part of the body. And that's why it's important that we have this IECT subcommittee meeting because we rely on our colleagues in other specialties to help us.

But the cytokine release syndrome is thought to result from a high magnitude of immune activation. Inflammatory cytokines such as IL-6 are released and activated by lymphocytes and myeloid cells. And the cascade has body-wide effects.

So it occurs typically within the first week of the aftermath of the infusion. But it can occur even several hours afterwards. In my experience, it occurred several days, just like on the trial, about two to three days afterward. Neurologic events can overlap with CRS as well, but can occur independently of this as well, as can be seen for the graph. And these side effects correspond with the acute expansion of CAR-T cells.

Cytokines such as IL-6, like I talked to you about before, and CRP, C-Reactive Protein, are elevated in patients who have cytokine release syndrome. It's hard to measure some of these things in real time. CRP is easy to measure in most cases. Another marker, ferritin, another marker that we use that can be easy to measure in real time. Most of our labs don't have the capability of a short turnaround time for IL-6. So we use, in earnest, CRPs and ferritins to help us determine laboratory-wise which patients might be at risk.

Because some of these lab values which are checked multiple times per day rise pretty quickly and slightly before we actually see clinical signs. This can be a warning sign to us. So these expand and go multifold from their baseline up. And you can see the CRP going up in milligrams per liter from undetectable to up to 300 or 400.

Peak cytokine levels also correspond to severity of CRS. The patients who went to the ICU-- you can see them in the triangles-- had high levels of peak IL-6 interferon gamma and also peak ferritin and peak CRPs. So these correspond very closely to the inflammatory response and also the clinical picture of the patient.

You can also see a marked increase in cytokines dependent on the burden of disease. So patients who have really high burdens of illness-- their peak cytokine release is also very high. And so when we see a patient who has 80% blasts or 90% blasts like Emily Whitehead had, we would be very scared for them to get CRS and be watching them even more closely than we would otherwise.

Patients who have a lower burden of disease-- and this has been meted out in multiple trials-- typically have less CRS. This is not an absolute. And patients who don't respond don't get CRS either and don't have a really high increase in cytokines, understandably so, because their T cells really aren't working against the tumors. There's multiple reasons for that, which I'll touch on at the end. But that's another topic for another time.

Treatment options for CRS-- primarily based on symptomatology, but there are various drugs that we can use. Tocilizumab is number one. And corticosteroids is the other specific therapy. So for patients who are or hypotensive, IV fluids. The patients who need oxygen, give them oxygen. A lot of it is supportive care.

Tocilizumab is an IL-6 receptor antagonist. This is approved for this indication at the same time that the CAR-T cells were approved. This medicine was available widely for juvenile arthritis.

One of the doctors at UPenn had a child who had juvenile arthritis, knew about this a drug. And they were measuring in the lab IL-6 levels and thought, well, maybe if I give him an IL-6 antagonist or Emily an IL-6 antagonist, she'll get better, which happened. And lucky for them that that happened, because the field was really in its infancy. And if this young lady died, their first patient, the trial may have been shut down.

So they used this medicine. They took it out of the pharmacy, gave it to her, and the response was pretty dramatic. She was on three pressors. And by one night and by the next morning, she was off pressors. And by about two days later, she was extubated. And we all know about this patient because she's been discussed in multiple-- I don't know her personally. but we all know about her very well because she's been discussed at almost every CAR-T cell conference and also major hematologic conferences.

So how do you assess these patients? First, you have to grade the CRS. If they're grade 1 and 2, typically, if the patient is healthy otherwise, you're able to monitor them and give them supportive care. If they're grade 3 or 4, almost without fail, you have to give them tocilizumab.

If a patient has comorbidities, otherwise has heart disease and becomes hypotensive and needs pressors, you want to give them tocilizumab earlier. If they have a healthy heart, healthy lungs, then you can wait a little while longer. So that's really the upshot of these next busy slides.

So we discussed this ad nauseam in our IECT subcommittees. And this is really lifted from our Sarah Cannon Network, which lifted it from the MD Anderson protocols, wherein they were able to grade their patients and treat them appropriately without having many adverse outcomes. There are variations of this within the community at large. There's no real universal consensus. We're still trying to get a universal consensus.

These drugs are living drugs. They have variations in them. In general, they cause the same side effects, but the onset and severity might be slightly different. So there is some debate. This is not a panacea. There's some debate about what the best therapy is and when to give it.

So we all agree on supportive care. We all agree about toci. We all agree about corticosteroids. But the issue is when to give them. So we do have to come up with some standard. And so this is the standard that we're going to adopt here at South Austin Medical Center.

Neurotoxicity or CAR-related encephalopathy syndrome-- one of the things that-- and these vital signs are every four hours. The neurologic testing is done, in some cases, every four hours, but at least twice a day. If a patient's at baseline, you can get away with twice a day. For patients having any changes at all, or if you see their lab values change, their CRPs start to go up, or their ferritins start to go up, you can increase the frequency of these neuro checks.

So the CARTOX 10 you can see at the bottom here-- it's sort of a mini, mini mental status exam where you ask the patient their orientation to year, month, city, hospital, president, name three objects, ability to write a standard sentence, and then counting backwards from 100 by 10. If they're able to get all of these-- they don't have any sign-- they don't get anything for this first row, if they are able to get only one or two questions right, they have grade 3 CRS straight away.

You want to measure for increased intracranial pressure by having your neurologist or ophthalmologist look at the patients eyes for papilledema if you at all suspect any deterioration neurologically. And also any seizures that occur-- if you have any seizure activity whatsoever, you have grade 3 CRS.

Acute CRS can occur-- or sorry, neurotoxicity can occur with CRS. And the treatment for that is tocilizumab. If it occurs delayed, most centers will give corticosteroids. Cerebral edema can also occur in these cases.

Monitoring, like we talked about in the neurologic exam, brain MRI, EEG in patients who've had any change in mental status or you suspect seizures. And in some cases, we'll do examination of spinal fluid. Dexamethasone is used as the steroid of choice in most cases for these patients because it has excellent blood-brain barrier penetration.

If you have grade 2 or greater neurotoxicity, you can put them on levetiracetam or Keppra. Some centers will put this on the patients more prophylactically at the start. However, we don't foresee during that here, as it's not something that's considered a standard across centers. Tocilizumab-- the infusion should be considered for grade 2 neurotoxicity and above if it's in relation to CRS.

And if patients do not have a good resolution of their neurotoxicity, then move on quickly to steroids. We used to think that steroids are detrimental because they're lymphotoxic to the efficacy of CAR-T cells. That's not shown to be the case in the trials. There's been no relation to the use of corticosteroids in the efficacy of our treatment.

So future work-- we all know as oncologists that the tumor microenvironment's hostile, especially for patients who have solid tumors, so lymphomas and other solid tumors-- breast cancer, colon cancer, you name it. There are Tregs that are in these tumors, myeloid-derived suppressor cells, tumor-associated macrophages. They increase their inhibitory ligands like PL1. And they also secrete inhibitory T cell-suppressive cytokines, like transform and growth factor beta, or TGF-beta, and IL-10.

The new CARs that are on their way and being tested in the lab and hopefully will be tested in patients soon are trying to address these things. And I'll show you some work on that in the next slide or two. There are multiple antigens of interest like HER2, EGFR, GD2, CA, PSMA that are being explored in vitro, and in some cases, in small trials in vivo in some of these big centers like Memorial Sloan Kettering and Fred Hutch.

So CAR-T cell 2.0 and 3.0 have already come into being. This is armored CARs and on/off switch CARs that I'm going to talk about. Split-receptor design CARs are being tested in vitro and in vivo where CAR-T cells can recognize two antigens at the same time, where you have to have two signals.

So there's no off-tumor effect. So things like EGFR, HER2, are expressed in normal cells. There are companies that are looking into having a switch on. So not only HER2 EGFR, but another antigen that would help activate the CAR-T cell in the right environment, right where the tumor is, and not have any off-target effects. So this is being worked on.

There's something called the synNotch system, where there's a transcription factor that's within the-- attached to a construct that's inserted into these T cells, wherein when a T cell encounters an antigen, that transcription factor is released and naturally expresses the CAR in these T cells and now allows the CAR to be expressed and go after an antigen after the construct is made.

So that these cells are put in where the CAR-T cell construct is not made. It's within the cell itself. They have to encounter one antigen of interest. And they will only be activated in the presence of tumor.

Armored CARs, or IL-12 secreting CARs, are something else that's exciting. These CAR-T cells excrete proinflammatory cytokines that we think increase NK recruitment and activation and anergic tumor infiltrating lymphocytes that are within the tumor cell that have tried to kill it but have become anergic to have the ability to reactivate them. And so this is something that's being worked on in multiple groups as well and may be in the clinic widespread pretty soon.

So updates for South Austin Medical Center-- tisagenlecleucel was approved for ALL back in August 2017. It was approved for non-Hodgkin lymphoma back in April, so just a month ago. And it should be the first product that's administered at South Austin Medical Center.

Our facility was visited multiple times by the company that has this drug and was approved to administer it. Our physicians were also approved via a REMS program. And we had to pronounce tisagenlecleucel for them to be able to approve us. If we weren't able to do that, then we weren't able to get on the REMS program.

But axicabtagene is another product that was approved for non-Hodgkin lymphoma back in the fall of last year. And we looked at that study. We plan on having this product available prior to the end of the year. And clinical trials are something that we're looking at as well.

There is a company in England or out of England that's looking at a dual-targeted CAR, focusing on BCMA, which we all may have heard of as oncologists, and another antigen called TACI via a natural ligand that they think may be better than what's being trialed right now. And we hope to have a trial for AML via T cell receptor-- T cell within the next year.

There's been a lot of talk about these commercial CARs and the cost of them. Medicare has not had an official policy on reimbursement for inpatients. And so although our center's approved, we are unable to give this medication at the current time, so today or tomorrow or the next week, until Medicare, I believe, makes a decision on the inpatient reimbursement, which will probably be in August of this year.

They've made a agreement, or they've made a policy for outpatient reimbursement, which would allow hospitals to cover the cost of these expensive medications. But the inpatient reimbursement would be for the DRG for the disease, which would be $15,000, $20,000 when these medications cost in the hundreds of thousands.

So we don't want to treat Medicare patients differently from any other patient. So HCA and South Austin Medical Center is holding off for the time being. We will have multiple clinical trials available towards the end of the year. So there'll be a lot of things occurring in the next several months to allow patients to stay here in Austin to receive not only commercial product, but promising CAR-T cells that are being experimented with currently. So that's all I have.

Yeah, good question. I don't think so. I think they have the data, but they haven't published it yet. A lot of these patients, as you know, that have double-hit and triple-hit lymphoma do poorly. And I think there were a good number of patients on the trial. I don't have the number in front of me. And it may be in the-- like, table 1 of patient characteristics in the trial. But I don't think they teased out response rates for them separately from the cohort as a whole.

The question was for patients who have CRS and neurotoxicity, would you measure the IL-6 level prior to giving the medication? The answer is, we plan to, but the turnaround time for that is days. So you don't have, unfortunately, days before you give the antibody. And it's approved for this, so we end up giving it.

MALE SPEAKER: So based on grade 3, grade 4?

SHAHBAZ MALIK: Yes, exactly, based on the grading clinically of the toxicity, yes. And we do have fairly good surrogate CRP and ferritin, but we don't have the specific cytokine that we have the antagonist for that we're giving. So we use surrogates, unfortunately, CRP and ferritin, just because we have a faster turnaround time.

And we can see them-- and in Stanford, even at a institution like that, we didn't have the fast turnaround time for IL-6. And we saw in patients, and there have been multiple presentations wherein that it's been shown that CRP and ferritin fall-- CRP's quicker in most cases than ferritin-- fall concomitantly with the administration of tocilizumab and with the resolution of the clinical picture.

MALE SPEAKER: What's the data with myeloma?

SHAHBAZ MALIK: Data with myeloma's pretty darn good. There's a company called bluebird bio that's working with the NCI that has a BCMA CAR. Their responses have been deepening. And the response rates, I believe, are on the order of 80% or greater for patients who are quad-refractory, penta-refractory.

So the data seems to be pretty darn good. And every time they've updated it, it's gotten a little bit better because of the clearance of the M proteins and the free light chains lags a little bit from the clearance of the plasma cells.

MALE SPEAKER: So even as a--

SHAHBAZ MALIK: At this point in time, we want you to refer anybody you think would be appropriate. If we are not able to offer them something here, we do have avenues to refer them elsewhere. But I think we-- I and Dr. [INAUDIBLE] have experience with these medications and know when it's appropriate to give them. So if we have a chance to evaluate the patient, even if we don't have them available here, we'd be happy to see them and refer them appropriately elsewhere.

MALE SPEAKER: OK, and who you'd like to have that?

SHAHBAZ MALIK: We've had several patients, and unfortunately, that we've had to send away just to get them the help that they've needed. There are waiting lists even at centers like MD Anderson that we've had patients sent over there that unfortunately haven't been able to get CAR-T cells in a timely manner. And there's multiple reasons for that. It's just getting through the system and getting put on an appropriate trial or commercial product.

MALE SPEAKER: Have you guys started on CAR-T cell [INAUDIBLE] with the lymphomas [INAUDIBLE]?

SHAHBAZ MALIK: So we're going to-- we have the approval from the company that makes tisagenlecleucel. So we should be able to treat patients. We aren't a pediatric center, so should be able to treat patients from the age of 18 to 25 who have ALL with this and are able to treat pretty much any adult patient with non-Hodgkin lymphoma as well.

We hope to treat later on multiple myeloma when we have the trial available here, and also for AML patients. The AML trial is going to be pretty-- or I shouldn't say pretty limited, but limited to patients who have HLA-A2. So there's a TCR construct that will recognize HLA-A2.

And they're looking at an antigen called PRAME, which is actually expressed on the majority of AML cells. So it's pretty sensitive, but you have to have HLA-A2. And we've looked back to see how many patients we've transplanted or we've seen that have HLA-A2, and it's about four in the past two years. So there are patients who we've seen that may benefit from that as well. The number is not high, but we don't know unless we test them.

So patients who have partial response to the medication that we get for non-Hodgkin lymphoma-- if they don't have a CR, I think looking for an allogeneic stem cell donor would be the most appropriate thing. We would have them in place before we even give the CAR-T cells just because we'd have to move quickly. If they go into a CR, I would say the answer is no because the results are so good with the CAR-T cells alone.

Now, the answer for ALL is-- the folks at the Hutch and the folks that you talk to at Penn would say do not allogen-- don't transplant them. Because the transplant data for patients who go into transplant with any positive disease-- their outcomes are dismal. If we're able to get them into an MRD negative state before transplant, then yes. If they went onto some salvage treatment after CAR-T cell, then we consider allo transplant.