I would now like to turn the call over to Christine Cassiano, Chief Communications Officer. Ms. Cassiano, please go ahead. Thank you, operator, and thanks to all of you for joining today on short notice. After the market closed today, Allogene issued a press release that provides a clinical update on our AlloCAR T program. The press release and today's webcast are both available on our website. Today's call will be led by Dr. David Chang, our President and Chief Executive Officer. During the Q&A, he will be joined by Dr. Rafael Amado, Executive Vice President of Research and Development and Chief Medical Officer, and Dr. Eric Schmidt, Chief Financial Officer. We will do our best to get to as many questions as possible. We ask you to limit questions to one per person so we can get to as many as possible. During today's call, we will be making certain forward-looking statements. These may include statements regarding the timing and ability to advance our clinical trials and regulatory matters, among other things. These forward-looking statements are based on current information, assumptions, and expectations that are subject to change. A description of potential risks can be found in our most recent SEC disclosure documents. You are cautioned not to place undue reliance on these forward-looking statements, and Allogene disclaims any obligation to update these statements. I'll now turn the call over to David. Thank you, Christine. Good afternoon. We recently issued a press release indicating that the FDA has placed a clinical hold on all our AlloCAR T clinical programs based on a single patient case in the ALPHA2 trial. While this is disappointing for Allogene, the field, as well as many of our stakeholders, I want to reinforce our conviction in the opportunity ahead. Between myself and Rafael alone, we have more than 15 years of experience in developing engineered cell therapies. Although this new and exciting field of innovation is uncharted, we know we are forging the way in allogeneic cell therapy, as we strongly believe it will be the next therapeutic option for patients. In the same way some of us encountered and addressed challenges with bringing one of the first autologous CAR T therapies to market, we feel confident that we will do the same here at Allogene with allogeneic CAR T products. The data generated from ALPHA trial supports a favorable clinical profile for ALLO-501A in patients with large B-cell lymphoma, which underlies our mission to provide allogeneic CAR T therapies faster and more reliably to patients suffering from some of the most difficult-to-treat cancers. We also recognize that today's news elicits a lot of scientific questions that have yet to be answered. Our team is working diligently to address these questions, and we are committed to communicating updates in a timely fashion. While we are not in position to provide a lot of answers today, we are working through this with a clear intention and the commitment to support the overall development of allogeneic CAR T therapies for cancer. Let me provide some background on this clinical hold. We reported information to the FDA on a patient with Stage IV transformed follicular lymphoma and c-Myc rearrangement, whose cancer was refractory to two prior lines of immuno-chemotherapy and additional radiation therapy. The patient was not able to receive an autologous CD19 CAR T therapy due to manufacturing failure associated with inadequate expansion of CAR T cells. Following infusion of ALLO-501A, the patient experienced Grade 1 CRS and Grade 2 ICANS, which required a course of high-dose steroid therapy. The patient subsequently developed progressive pancytopenia, and bone marrow biopsy showed aplastic anemia and the presence of ALLO-501A CAR T cells with a chromosomal abnormality. Early translational data showed that the CAR T cells expanded, peaking on day 28, and was undergoing contraction thereafter. The patient had a partial response to ALLO-501A and subsequently underwent allogeneic stem cell transplantation. Prolonged cytopenia requiring rescue stem cell transplantation has been reported in autologous CAR T therapies. An investigation is underway to further characterize the observed abnormality, including any clinical relevance, evidence of clonal expansion, or potential relationship to gene editing. As we work with FDA to resolve this situation, the FDA continues in parallel to actively review the end of phase I material submitted in anticipation for an ALLO-501A pivotal phase II trial. I want to reiterate that patient safety is our highest priority. We are committed to working closely with the FDA to evaluate any potential clinical implications from this single-patient report to determine next steps for advancing ALLO-501A and our clinical programs. Importantly, Allogene has dosed more than 100 patients with its gene-edited AlloCAR T product. We believe the data generated from ALPHA trial supports a favorable clinical profile for ALLO-501A in patients with large B-cell lymphoma and look forward to presenting updated data later this year. We are grateful for the partnership with the patient community, clinical investigators, our scientific advisory board, and the FDA as we work diligently toward understanding any clinical significance of these findings to support the ongoing development of allogeneic CAR T therapy for cancer. I would like to take the opportunity to thank our employees, our partners, our trial participants, and our clinical investigators for their continued hard work to advance our AlloCAR T products. We are privileged to be at the forefront of an incredibly innovative and important, albeit a complex field, as we look forward to continuing to work with the FDA to promote our efforts. We could not be more proud of the work accomplished each day by our team members, who are committed to bringing the first allogeneic CAR T therapy to the many patients in need. We will open the call for questions. At this time, if you would like to ask any questions, just press star one on your telephone keypad. If you would like to withdraw your question, just press the pound key. Your first question comes from the line of Salveen Richter from Goldman Sachs. Your line is open. Thanks for taking my question. Did you find the chromosomal abnormality in the manufacturing lot that was dosed for this patient or in other lots? Yeah. The question about whether this was seen in the manufacturing lot or our other lots. Our lots, before they are released, undergo extensive, and I should say state-of-the-art release testing that includes assessing any kind of chromosomal anomalies. Certainly all the lots that were used in the clinical trial passed the release test. Given the finding, we are investigating every possibility that could have contributed to the observed finding in this single patient. Thank you. Your next question comes from the line of Marc Frahm from Cowen and Company. Your line is open. Thanks for taking my questions. Sorry for this news. When you look in the bone marrow biopsy, do all of the ALLO-501A cells that are present have the abnormality? Is it just some of them? In that case, what percent, and are you able to detect it in that circulating samples when you talk about expansion and contraction? Yes, this is Rafael. In the karyotypic analysis, it's a fraction of cells that are detected with this abnormality. The CAR T cells peaked, and then they started to contract, and obviously that includes that population. We need to look more carefully with molecular assays to really know the kinetics of the clone in question. Okay. Are you people say with the abnormality that's being detected, is it at the site of the integration of the lentivirus? Is it similar to where you were cutting with the TALEN? Just where is it located in the genome? Yeah, Marc, this is Dave Chang. Let me answer that question. We know the chromosome location. It's chromosome 14. Other than that, in terms of where the changes occurred, is currently under investigation. Okay. Thank you. Your next question comes from Michael Yee from Jefferies. Your line is open. Hi. We had two related questions, maybe that counts as one. The first was, what, in your opinion, is the ultimate clinical ramification of what would happen and what could happen here, given the chromosomal abnormality? Can you talk about what would happen? I thought the cells would eventually go away. Maybe just talk about a little bit about the clinical implications and what would come about from this that would be concerning given the risk-benefit of the actual drug. Thank you. Yeah, Mike, let me try to answer the question. This is still very early. I will not be able to answer all the questions. We are trying to understand, first of all, whether this is a clinically relevant finding. Obviously, this is observation that has been made, and our approach is trying to better characterize what exactly happened to the chromosome, and that may require some additional investigation. As previously asked by Salveen, we are also looking to see when these changes may have occurred. Those are some of the ongoing investigation. Let me also reiterate, this is a single case report out of more than 100 patients that we have tried. This is not something that we normally look for, because most patients do recover, and CAR T cells disappear from the patient's body. There is many unknown questions, and we are working diligently to answer these questions. Thank you. Yes. The next question comes from the line of Jason Gerberry. Your line is now open. Oh, hey, guys. Thank you for taking my question. I guess I'm just trying to get my head around. It seems like there's potentially a lot of confounding variables here. Patient got prior immune chemotherapy, radiation, high-dose steroids, potentially got conditioned for autologous CAR T, but didn't get that autologous CAR T. Just wondering if you can provide any context for some of these confounding variables and how you're going to adjudicate that. Thanks. Yes. There are a lot of factors that could have contributed to cytopenia. All these patients are heavily pretreated, as you know. As David remarked, they couldn't make a graft, which means the lymphocyte count was low, and other lineages were also low. Whether or not that contributed to the overall cytopenias, it's really speculation. In general, patients that are heavily pretreated, that has been associated with cytopenias in the past. Cytopenias are seen in the autologous setting. This has been looked at, and there are theories that have been published. It's actually in every label of every approved product. There's been instances where rescue with bone marrow transplantation has been required. It's not really, unfortunately, that uncommon to observe this complication. Got it. Thank you. Your next question comes from the line of Michael Schmidt. Your line is now open. Hey, guys. Thanks for taking my question. I guess, Rafael Amado, when you go about your clinical and your investigation into this, I guess, what are possible or hypothetical explanations for that chromosomal abnormality that you will look into? What do you think you will need to do eventually to potentially move the clinical hold? Yeah. Michael, that's a great question. Let me just sort of talk about our some internal working hypothesis. Obviously, when you encounter problems like this, we have to be methodical, and we have to make a science-driven approach about finding out how this happened. Having said that, one has to understand that there has been several number of publications, in fact, with the use of gene editing nucleases, chromosomal structural changes can occur. These changes include simple things as non-homologous end joining, as well as large chromosome deletions, sometimes translocations, or inversions. That is one investigation that we're doing. The second one, and I think this is something that not many in the field appreciate, but T cells, as they undergo rapid expansion, it has been well documented that they acquire changes that includes mutations or deletions or inversions. Certainly, CAR T cells, as they encounter antigens, they can undergo a pretty rapid expansion. There are these two different sort of somewhat different hypotheses, and that is currently our main focus of investigation. Very helpful. Thanks. I guess, do you have a timeline or an FDA meeting coming up, and how should we think about, ultimately, the resolution of this? This is a very dynamic period. Certainly, we are communicating the information as we are learning from what FDA has told us. We need to better understand FDA's questions and, hopefully, with that, we will better understand what needs to be done to come out of the clinical hold. Okay. Thank you. Your next question comes from the line of Luca Issi of RBC Capital Markets. Your line is now open. Oh, great. Thanks so much for taking my question. Maybe wondering if you have done any RNA-seq analysis on the sample. Wondering if you can provide any color on whether the chromosomal abnormality actually has led to any change in the transcriptome of the cell. Maybe bigger picture, obviously, you're doing an extensive investigation. In my mind, worst case scenario is that you see some evidence of clonal expansion. Wondering if you can articulate what would be the best case scenario out of this analysis. Thanks so much. Yeah. Luca, this is a great question. As you can imagine, there's a whole host of assays that are taking place and others that will take place once we have interaction with the FDA. We want to sort of reserve any sort of opinion on results of assays or what types of assays we're doing until we actually have a dialogue with FDA and know exactly how to address their concerns. Please stay tuned. Apologies, I can't really answer your question fully, but we will give you information as soon as we have it. Got it. Thanks so much. Your next question from Mark Breidenbach of Oppenheimer. Your line is now open. Hey, good afternoon. Thanks for taking the question. David, I'm just wondering if you're seeing any potential need to revisit the notion of a suicide switch technology with your AlloCAR cells, sort of like what you had built into the ALLO-501 version before switching to ALLO-501A. If you see value in potentially reintroducing that sort of technology into the rest of your product line? Thanks. Mark, let me take that question. Suicide switch always has been a consideration with any CAR T therapy from the early days of autologous CAR T therapy. I think in the CD19, the question around the usefulness of suicide switch, I think that has been never really shown to be necessary for the CD19. With that background, in terms of what else we will be doing, I just want you to understand that this is very early sort of stages of investigation, and we will follow up with additional communications and thoughts as we better understand what's going on with this case. Okay, thanks for taking the question. Your next question from Raju Prasad of William Blair. Your line is now open. Thanks for taking the question. I think the hold is across all trials. Can you just give us a sense of the, maybe broad sense of the release criteria that you have underway, and is it similar across all trials, or are there specific differences in release criteria? Thank you. Raj, let me take that question. At this point, it's too early for us to comment about how FDA is thinking. It was a bit of a surprise that they placed a clinical hold on all our clinical trials. We have to find that out from the FDA. Sorry that I can't give you any more clarity on that, answers to that question. Your next question from Benjamin Burnett of Stifel. The line is now open. Thank you very much. I wanted to follow up on an earlier question, just around the notion of the suicide switch and getting rid of product if needed. I guess when this was discovered, what was the clinical course of action, and were steroids given? I guess if they were they effective at clearing the product? As we said in the prepared statement, there was cell expansion. After it peaked on day 28, it was contracting as frequently seen in the CAR T cell expansion profile. Essentially, the observation is made on very limited number of T cells from the bone marrow biopsy that was initiated by the investigator. That's what we know. We will let you know more as we better characterize the kinetics of the cell expansion. Is there a next question? Yes. Next question from Asthika Goonewardene of Truist Securities. Line is now open. Hi, this is Bill. I'm on for Asthika Goonewardene. I'm sorry about the unfortunate news. I had a question regarding the day 28 expansion. Could you remind me if that's typically seen, or is that within the range of the mean, or do you think this chromosomal abnormality could have contributed to it shifting away from the range of the normally seen? Thanks. Yeah, this is within the normal range of cell expansion that we are accustomed to seeing in our product. In fact, I would say this is very similar and representative of 4-1BB containing chimeric antigen receptor construct. Thank you, David. All right. Next question from Daina. Thanks for the question. Our next question from Daina Graybosch of Leerink Partners. Line is now open. Hi. Thanks for taking the questions on obviously a tough revelation. Obviously, the patient care is the most important thing here. I just had two questions. One, is there any, at least, initial evidence in terms of the disruption around the chromosome for the TCR knockout on chromosome 14? The second question would be, can you just clarify a little bit more what is initially the concern around the clinical linkage here, given the patient probably had fairly degraded bone marrow ahead of ever receiving the therapy. Is there some sort of evidence that we've seen that the CAR T positive cells that were put into the patient are somehow attacking the bone marrow or some other phenomenon that would give us pause for clinical concern here? I think we're all kind of struggling with that linkage right now. Thank you. Yeah. In terms of the reason for bone marrow biopsy, our understanding was that was done to evaluate pancytopenia that was observed in this particular case. I would say that's a routine clinical investigation when somebody has a lower blood count. I don't know whether I can add anything more. In terms of the first question, can you just remind me again on the first question you had, Daina? Yeah. If the space around the edit, presumably on chromosome 14 for the TCR knockout, is that in any spatial relation to the chromosomal abnormality itself? At this point, we do not have enough information on where the changes occurred on the chromosome. That's part of our initial attempt to find out where the chromosome flipping occurred. Once we have that, we will have much better understanding. Stay tuned. We are working feverishly to answer some of these questions. Okay. Thank you. All right. Thanks, Daina. Our last question from Kalpit Patel of B. Riley. Your line is now open. Hi, this is Yuan on for Kalpit. Thank you for taking our questions. For the reported pancytopenia, is it treatable through stem cell transplantation? Our second question is that, for these abnormal T-cells we observe here, is there a way to eliminate them, like using chemo or maybe another line of treatment? Thank you. If I understand correctly. Your first question was whether transplantation is a treatment for aplastic anemia, which the answer to that is yes. There are medical treatments, and then there are transplantation treatments. The physician that's caring for this patient has chosen to do a bone marrow transplantation. With regards to the second question, can you please repeat it? Yes. Is there a way to eliminate this observed abnormal T-cell? I see. Yes. Thanks for that. As we've been saying several times, the cells have contracted, and they are becoming barely detectable. The patient has already undergone conditioning for the bone marrow transplantation, those cells are probably eliminated with the conditioning that is given to transplant the patient. Yeah, that's very helpful. Thank you. That concludes our question and answer session. I would like to turn the conference back over to management for any additional comments. Yeah, this is Dave Chang. Thanks for joining us today. As I've said, we believe we have a tremendous opportunity to deliver a first-in-class therapy for patients. Our team is working tirelessly, and we are committed to communicating with transparency as we have more information to share. Operator, you may now disconnect. Thank you, ladies and gentlemen. Thank you for your participation in today's conference. This does conclude the program, and you may now log off and disconnect.