Good morning and welcome to Marker Therapeutics' Webcast to discuss the phase I clinical update from the APOLLO study MT-601 in relapsed lymphoma. At this time, all participants are in listen-only mode. Following prepared remarks, the webcast will include a Q&A session. You may submit questions at any time using the Q&A function on your screen. Please note this call is being recorded and will be available for replay on the company's website following today's event. I'd like to turn the call over to Maria- Bernadette Madel, Director of Corporate Operations for Marker Therapeutics. Maria, please go ahead.
Thank you and welcome everyone to today's webcast. Before we begin, we would like to remind everyone that today's webcast will include forward-looking segments. These segments are based on current expectations and are subject to risks and uncertainties that may cause actual results to differ materially. We encourage you to review the cautionary statements and risk factors described in our most recent SEC filings. We will now pause for a moment to allow you to read our forward-looking statements. Thank you. With that, I'm pleased to introduce Dr. Juan Vera, President and CEO of Marker Therapeutics, as well as co-founder of the company and one of the developers of this technology. Dr. Vera will provide an overview of the data from the company's phase I APOLLO study of MT-601 in relapsed/refractory lymphoma, which was announced in the press release earlier this morning. We're also happy to have Dr.
Geoffrey Shouse joining us today. Dr. Shouse his Assistant Professor at the Department of Hematology & Hematopoietic Cell Transplantation , City of Hope, Los Angeles County, California, and he is one of the PIs in Marker's phase I APOLLO study. Dr. Shouse will share his perspective on the study and the broader compassionate lens. Before we open the floor to your questions, we will return to Dr. Vera for final comments. As a reminder, questions can be submitted at any time throughout the session using the chat. With that, it's my pleasure to hand things over to Dr. Vera.
Thank you, Maria, and thank you to everyone for listening. We're really excited to be here today to highlight our progress in our clinical study in MT-601 in patients with lymphoma. Marker Therapeutics is advancing the MART-T cell technology, a technology that relies on millions of years of immunological evolution to provide a product that is capable of recognizing hundreds of epitopes present in the tumor, and in this manner, providing a treatment that can avoid the efficacy of neoadjuvant medications present in cancer cells. This technology was developed at Baylor College of Medicine, where we have generated clinical proof of concept. In addition to that, the company has been sponsored by non-dilutive funding, including NIH, FDA, and CFRS. Today, we're going to be providing a clinical update to MT-601 in patients with lymphoma into our APOLLO clinical study.
Before we do that, let me just walk you through the MART-T cell technology and the mechanism of action. Next slide, please. Next slide. Thank you. If we look at this representation, we see that the MART-T cell product is generated from particular blood T cells, which are isolated, stimulated with overlapping peptides, with the purpose of enriching for tumor-reactive T cells, and in this manner, providing patients a product that is capable of recognizing multiple targets present within the cancer cells. Importantly, we're able to do so without the need for genetic modification or genetic enhancement. In this manner, this is a natural product that we have now tested in the clinic with now having evidence of clinical activity and an excellent safety profile. Next slide, please. This is a quick overview into our manufacturing process.
We're really excited now to start a strategic collaboration with Cellipont, a CDMO located in Houston, Texas, a vendor that will be responsible for the manufacture of this product in our future clinical study as well as commercial launch. As you see in this schematic, this is an autologous process, which our current base event time is about 20days- 25 days. The final drug product is collected, preserved, and sent to the clinical site in a trial manner where it can be then administered. Next slide, please. This is a representation of our current pipeline. As illustrated here, our lead asset is MT-601. Today, we're going to review those clinical results. Next slide, please. MT-601 is a clinical study that we're really excited and is now developing a MAR technology, which recognizes six different tumor-associated targets.
The results that we're going to be reporting today are results from a multicenter clinical study across the U.S. Next slide, please. The reason we are excited about these results is, one, the first objective is to recapitulate in a multicenter clinical setting observations from an academic study conducted at Baylor . This study was published in the Journal of Clinical Oncology, where we were able to demonstrate the clinical activity of this technology in patients with lymphoma. Now, as part of the APOLLO study, our objective is, first, to recapitulate these results in a multiclinical trial setting, and two, see if we can even improve upon these results, as now we have performed several enhancements to the process as highlighted in the right-hand side: more antigens, more dose, and a simplified manufacturing process that can yield a product that is four times more potent. Next slide, please.
We can see here that this is the clinical study design. Let me walk you through the structure. This clinical study has two components: a dose escalation followed by a dose expansion. As shown here, the dose escalation ranged from 100 million- 400 million cells. As shown in the right-hand side, this is open to patients with different types of histopathologies, including the DLBCL. Today, we're going to show data on 24 of these patients. Importantly, as shown in the bottom of this slide, since June 17, the SRC has deemed the dose to be safe. As a consequence, we're now going into our highest dose level ever explored in humans, which is 400 million cells, as our dose expansion in patients with DLBCL CAR r elapse. This is important as this will be the foundation of our future clinical study. Next slide, please.
These are the results that we have today. We're really excited to report a CR rate of 50% and an overall response rate of 66% in our patients with non-Hodgkin lymphoma, patients that are heavily pretreated, and for many of which there's no treatment options. We consider this to be really remarkable in terms of the clinical benefit that it can provide to patients. If we go there to the next slide, and we examine the durability of responses, we see that of these patients, three of these patients have been in complete response for more than a year, and five patients have received the benefit of clinical responses for more than six months. If we go to the next slide and look into this data in more detail, we see that many of these patients have different types of histopathologies. Many of them are DLBCL.
They have received CAR T cells as well as bispecific. Despite failing to these prior lines of treatment, we're observing that MT-601 is capable of providing complete responses, which are durable. If you pay attention on the left-hand side, I will point out that these patients have received clinical benefit despite receiving the lowest cell dose explored in this study today, which is 100 million- 200 million cells. From this perspective, I'm really excited and believe that these results we're going to be able to recapitulate if not improve, as now we move into our highest-d ose level of 400 million cells. If we go into the next slide, we can see that the highest dose level ever tested in humans, which is 400 million cells, has shown not only to be safe, but we also have seen objective responses.
These are nine patients, Hodgkin lymphoma patients, that have received the highest dose level of 400 million cells, where we're seeing an overall response rate of 78% and a complete response rate of 11%. These are clinically meaningful observations. As illustrated here on the right-hand side, this is actually a patient with Hodgkin lymphoma from Abdul Hakim, which is one of our PIs from the study from Kansas. This patient had a partial response. Despite this being classified as a partial response, you can see that this patient had a high level of disease burden, and it was controlled after the administration with MT-601. Next slide, please. Perhaps one of the elements that makes this technology very different to other alternatives is the safety profile.
What we have seen today is, as we explored 200 million and the highest dose level of 400 million cells, we have seen an excellent safety profile without dose-limiting toxicities, no antigens, and the only cytokine release syndrome that's been reported has been level 1 in two patients that have been just relief fever and response in absence of additional treatments. In addition to that, we continue to monitor the long-term toxicities. Again, remember, this is a natural T cell product that does not require genetic modification, and as a consequence, it's not really subject to some of the long-term cell transformation that have been observed in the cell therapy space using CAR T cells.
With that, we're really excited to report today these clinical observations showing the efficacy of our technology in patients that are heavily pretreated, as well as confirming an excellent safety profile even as we go now to our highest dose level. With that, let me hand over to Maria. Maria?
Thank you, Dr. Vera, for the insightful presentation. That was really a great overview of the data I wanted to give you. We are happy to have Dr. Shouse with us today, who has been directly involved in the study as a Principal Investigator at City of Hope. Welcome, Dr. Shouse, and thanks for joining us today. We're looking forward to hearing your perspective on the trial and how Marker's findings compare with our clinical test.
Thank you. Thanks for the opportunity to speak about some of the exciting results that we've seen on the study. I'll start out by going through the results on several of the patients that have enrolled with large cell lymphoma. The first one shown here was refractory to three prior lines of therapy, including CAR T cell therapy. With MT-601, you can see at the eight-week time point that their disease has gone into remission. Importantly, the patient had no toxicity associated with the treatment. On the next slide, you can see another patient, this one going through eight prior lines of therapy, including CAR T cell therapy. Again, showing at eight weeks, complete metabolic response was achieved. Again, minimal toxicity seen in this patient. No CRS, no neurologic toxicity.
This patient, shown on this next slide, achieved complete metabolic remission with prior bulky involvement of the spleen by four weeks after MT-601 treatment. This patient had both prior bispecific antibody and prior CAR T, a total of 10 prior lines of therapy. This last patient had cutaneous-only relapse of DLBCL, was initially treated without lymphoid depletion, had a partial response, then was retreated with remaining cells with lymphoid depletion, and ended up achieving a complete metabolic response, again, with minimal toxicity. Seeing this promising preliminary efficacy and this, in my opinion, incredible safety profile, we can dive in and see what the treatment landscape and CAR T relapse DLBCL looks like. On this next slide, you can see unmet needs in DLBCL persist.
The treatment landscape has seen dramatic changes and continues to undergo changes associated with the incorporation of novel therapies, including cell-dose-based therapies like CAR T and bispecific antibodies. Even with these changes, however, unmet needs persist, including patients that relapse after CAR T or patients who are now eligible for CAR T due to toxicity. MT-601 has demonstrated exceptional safety, and we've seen the preliminary efficacy. It carries the potential to fill many of these unmet needs. On the next slide, we've outlined some of the basics for the current treatment landscape in CAR T relapse DLBCL. In the upper left, you can see bispecific antibodies are likely the best available treatment we have that's FDA approved in this setting. However, long-term follow-up suggests that the durability of response is not completely clear, and it's unclear whether these are curative therapies or just treatments that can buy patients more time.
Below that, we see a combination of tafasitamab and lenalidomide, which itself has limitations in terms of efficacy and durability. Also, in the total study leading to its approval, high-risk patients were excluded from the study. In the upper right, antibody drug conjugates, such as polatuzumab and loncastuximab, have shown efficacy. For Pola, it's mainly been found to be efficacious in combination with other treatments. Right now, the most common use of Pola is in the frontline setting as part of Pola-R-CHP. If it's being used in the frontline, its utility in subsequent lines of therapy comes into question. In addition, with loncastuximab, although it has some efficacy in the CAR T relapse setting, the number of patients included in the study that were CAR T relapsed was rather small. The toxicity profile of loncastuximab is significant, with a significant proportion of patients on the study having edema.
In the bottom right, we have other treatments like selinexor and the recent approval of tafasitamab. However, these have not been widely adopted and have limitations in terms of their efficacy and toxicity as well. Looking to the future, there are many therapies currently in development. These include allogeneic CAR Ts, humanized CD19 CAR T with IL-18 expression, in vivo CAR Ts, other T cell engagers, dual and tri-specific CAR Ts, CAR NKs, and other small molecules. The main limitation of these therapies that are under development is they're limited. Many target one, possibly two antigens, up to three at times. That leads to a limitation of antigen escape for a mechanism allowing for resistance to relapse. They also have short-term durability based on an initial study. There may be increased toxicity as the number of targets are expanded in CAR T.
In addition, the bispecific antibodies and B- cell engagers may end up moving to earlier lines of therapy. That's still an unmet need in this study. Taking this all together, on the next slide, we see that the current therapies have narrow recognition and short-term durability. Unlike T cell engagers and CAR T cells, the MT-601 products do not depend on antigen expression for efficacy. Agnostic molecules like MT-601 could address the current unmet medical needs in large cell lymphoma. In summary, the last slide, MT-601 is poised to fill the unmet needs in DLBCL. Despite the promise of the current novel therapies being evaluated, an unmet need persists. MT-601 has demonstrated, again, exceptional safety and preliminary efficacy and carries the potential to fill many unmet needs.
Thank you, Dr. Shouse, for sharing your valuable perspective. This is a super nice statement as well. It's always important to hear the insights from those working directly with patients. Your comments really highlight the potential of MT-601 for both the patients and how it could be developing treatment directly. Before we go into the Q&A session, we will hand it back to Dr. Vera for final comments.
Thank you, Maria. Thank you, Dr. Shouse. I really appreciate your insights. Go to the next slide, please. I would just like to make some closing remarks. I think that definitely with our technology, we have something that is quite unique and different. That difference is precisely derived out of the mechanism of action. The ability of MT-601 to target multiple antigens in a natural manner addresses perhaps one of the major obstacles of what I will consider as an effective immunotherapy. I think Dr. Shouse alluded to that, which is a restricted target profile that multiple of the current strategies are limited by. MT-601 is able to recognize multiple antigens simultaneously, and in that manner, addressing and overcoming one of the barriers which multiple technologies are currently limited by. We're really excited by the results we're seeing today.
We thank all the participators in the study, the physicians, research coordinators, and definitely the patients. We will continue to work diligently to advance this clinical study with the objective of taking this product into the market. As illustrated in this slide, I think that this highlights a significant milestone as we have now finalized our dose escalation. We have observed no dose-limiting toxicities. We have confirmed the early observations from the Baylor College of Medicine clinical studies. Now we're really excited moving into the dose expansion, which will concentrate enrollments in DLBCL CAR T cell therapy relapse and bispecific antibody therapies relapse patients, which will be the foundation of our future pivotal study. We look forward to continue communicating our progress and clinical outcome. If you guys have any questions, please feel free to reach out to the company. We'll be always available. Thank you very much.
Thank you, Dr. Vera. Thank you, Dr. Shouse. At this time, we will begin the Q&A session of the week. The first question, Dr. Vera, the APOLLO study says that 60% of the non-Hodgkin lymphoma patients have a complete response for several occasions, maintaining response for more than 12 months, despite a median of CAR T far less than 3 months. How do you view this durability profile relative to CAR T cells? Where do most of the relapses occur within a year? How would you compare the durability of MT-601 relative to CAR T cells as well as bispecific reception and shorter remission dates?
Sure. Yes. Good question. Let me characterize the clinical landscape, right? I think that these observations are considered to be remarkable, particularly given that we're seeing them in patients that are CAR T relapsed and some of them, which are also bispecific relapsed. There's not a lot of literature in that regard when we look into the overall survival of these patients. However, from our best assessment, you basically see an overall survival for patients that are DLBCL CAR T relapsed, which is about five months, right? Without a doubt, the longer response is less than six months to a year. That's very reasonable from a clinical perspective. I think anything too bad doesn't happen in that context. Not all CAR T relapsed bispecific relapsed patients. Also, as we just heard a moment ago from Dr.
Shouse, the clinical alternatives, despite many of the things that are characterized in the literature, are not that great when it comes down to a patient that is DLBCL and has failed CAR T cells, right? I think those are the biggest issues in terms of what kind of treatments can bring to these patients in terms of the efficacy as well as the risk of toxicity. I think that the question is valid, right? Which is, how do we characterize the results we're seeing today against the competitive landscape related to products that are approved, products that are coming into the market, and the overall survival of these patients? I think that is quite significant given the fact that, again, you're talking about heavily pretreated patients that the current treatment options are not really effective. You have to combine that in an excellent safety profile.
I think that the combination makes this a very exciting and powerful clinical observation.
With CAR T cells and reduced neutrophil depletion, is there a study to discuss results on neutrophil depletion? I'll include the final MDT trial results.
Yeah, that's an excellent question. I think that we have seen objective responses from our technology, even in the absence of neutrophil depletion, right? I think we briefly reported those observations in our past clinical release. I think the implications have been profound because of the proof of inferential neuropathic expansion of CCLP T cells. This phenomenon has been, I think, recognized across multiple different treatment programs. We have been able to recapitulate those observations. A few months ago, we actually reported our findings that we actually have seen an expansion of resistant CAR T cells from implication. Now, anything that you could hope to reconcile with what was fighting for breaking up neutrophil depletion, we have not seen a detrimental effect in the safety profile. One thing that from my perspective, I wanted to point out is neutrophil depletion is not the problem.
The problem is the side effects derived when neutrophil depletion is combined with other cells treatment, such as cytokine release syndrome and long-term neutropenia, heavy pressure, and so on and so on. I think that from that context, neutrophil depletion has not had those effects in our technology, right? The importance of that is that that provided a clear guidance in terms of our direction going forward for our registration study. Going forward, the large database that we're seeing today in patients that have neutrophil depletion and going forward, patients' global conditions. Based on the neutrophil depletion as a regimen for the administration of the cells.
How can we document the registration study?
Yes, that's an excellent question. I think that this is something that is going to become our next critical milestone, which is advancing something specialized and safe to hold for a future approval. To that end, I think what's most important is how this is a high unmet medical need, right? I think that is characterized by the limited options that many of these patients have. They have a lot of toxicities. They have no strong treatments. I think that when you take that in context with the result that we have seen today, you have a very strong case to make in order to have this product advanced for a federated approval, right? We still have to meet the FDA and the comparable protocol. I believe that our clinical data have a very strong support for that particular clinical requirement.
In that context, I believe it is able to get the product approved with a single arm based on the clinical study. Again, being able to find details in terms of the site of the clinical study still has to be discussed in the upcoming conversation with the agency.
Thank you. What are the thoughts on MT-601's experience with the HIV relapse?
Yes, absolutely. I think that that is definitely the future, right? We recognize the reality, and we are very strategic when it comes down to deploying our product. As a consequence, we are advancing MT-601 DLBCL CAR T relapse patients with the objective of demonstrating in a patient population with an unmet medical need that without a doubt, this treatment works. It does so in providing an excellent safety profile. The reason to do that is so that we can get approval in, you know, otherwise we have a restricted label, but we get approval and start changing the dynamics of the company and get to a point of revenue. The objective soon after that is extending this to an earlier line of treatment.
I think that from what we have seen today, based on our data, the Baylor data, I think that it's reasonable to assume that that is a realistic future where we'll be able to move these treatments even before CAR T cells.
For the dose expansion, you mentioned that you will focus on patients with DLBCL who have relapsed after CAR T cells. You also mentioned the favorable safety profile of MT-601. Would you also consider enrolling patients who relapsed after CAR specifics in the dose expansion cohort?
Yeah, that's an excellent question. Allow me then to clarify. I think that the first thing to understand here is that when we look at DLBCL, that's a highly fluid clinical space, right? I think that recently we have seen the approval of bispecifics. We also see bispecifics now moving into an early line of treatment. What I'm trying to say is that it is at this point very difficult to predict the final evolution of the clinical landscape for DLBCL CAR T relapse patients, right? It is likely to assume that bispecifics will move potentially in a clinical application before CAR T cells due to the fact that they're easier to administer, given the fact that they're off the shelf. As a consequence, what we're envisioning for the patient population is to treat patients that are DLBCL CAR and/or bispecific relapse.
From that perspective, have a more inclusive criteria that will be able to encompass patients that need one or the other or both, given the fact that this is still an uneven clinical landscape.
Thank you. We received many questions. I think we have time for one more case. Going back, I understand it's a bit hard. Thinking from a Q2C, you've ever seen the reverse effect effective at 100 million- 200 million cells. What is now the scientific and clinical rationale to move into the higher doses and the dose expansion in patients with DLBCL?
Yeah, that's an excellent question. I think that the overall premise and the things you've been seeing both is that more is better, right? I think that there is a practical viewpoint. I think that especially in the field, we have seen a combination of three novel cell refracts, including CAR T cells, where there is an appropriation of both treatment of those cells. They do not need for cells to expand. There is an effective measure that they're able to provide more reliable and more objective responses, right? Again, the overall viewpoint is that more T cells will definitely provide a higher effective target ratio and therefore deeper responses to patients. I think that many different programs have an indication in terms of pushing the boundary as you go to more cells. They also increase toxicity.
I think that the impact here that we've observed is that despite going to the... If I could step back and look at those two terms, we have advanced in the spike from cohort in both diffuse large B-cell lymphoma (DLBCL) CAR T relapse and for bispecific relapse patient population with our highest dose level using attempts. If we're incrementing this by improving, we think that it's possible that we can develop as we know that we've implemented a bit more cells. We don't necessarily affect them with an excellent safety profile, which again makes this treatment very different. Again, we still have to collect that data, but I think that there is good scientific...
If you look at part of the DRFN, concentrate on any patient that has DLBCL and/or bispecific relapse, if we had those levels, I think that that would be a very strong foundation of where we're going into the last clinical study for this year.
Thank you very much for your overview and very nice summary. We received a lot of questions, as I mentioned. I would like to thank everyone for the questions that you've given to us. I wanted to have a look at and see if... This concludes protocol.
May I?
Yes.
Thank you.