Good morning, welcome to the SELLAS Life Sciences Group KOL event. At this time, all attendees are in a listen-only mode.
A question and answer session will follow the formal presentations. Kindly note that we'll be taking verbal questions from our covering research analysts and then written questions from the remainder of the audience. If you'd like to submit a question, you may do so by using the Q&A text box at the bottom of the webcast player, or by emailing your questions to questions@lifesciadvisors.com.
As a reminder, this webinar is being recorded and a replay will be made available on the SELLAS website following the conclusion of the event.
Before we begin, I'd like to make reference to the forward-looking statement slide on the screen. I'd now like to turn the call over to your host, Dr.
Angelos Stergiou , founder, President, and Chief Executive Officer of SELLAS Life Sciences Group. Please go ahead, Angelos.
Thank you very much, Tara.
Good morning, everyone, and thank you for joining us today for our KOL webinar to discuss SELLAS' Phase III clinical trial of galinpepimut-S or GPS in patients with acute myeloid leukemia in second remission, the REGAL study.
We're privileged to be joined by renowned hematologist oncologist, Dr. Omer Jamil , who's a REGAL study principal investigator at the University of Alabama at Birmingham, one of the highest enrolling REGAL sites. Dr. Jamy will share his perspective on the AML treatment landscape, focusing on patients in second complete remission and will share his sentiment around the REGAL trial.
To preserve integrity of the study, Dr. Jamy will not reveal or discuss any REGAL patient-specific outcomes.
At SELLAS, we believe that GPS has the potential to change the face of treatment for leukemia as it is a highly differentiated immunotherapeutic that has demonstrated measurable clinical benefit in extending the lives of AML patients in remission, a growing unmet medical need. Clinically and statistically significant survival benefit was previously reported in our Phase II study in patients with AML in second remission who received GPS monotherapy, which is the same population as the Phase III trial.
In the Phase II study, we observed an almost 16-month differential, 21 months versus 5.4 months with a p-value of 0.02, and a substantial difference in leukemia-free survival.
In November of last year, we made refinements to our ongoing Phase III REGAL study protocol based on emerging aggregate study data, which suggested that the median overall survival in the pooled study population is likely considerably longer by a factor of 2x than the initial estimates which drove our original statistical assumptions for study design. We continue to remain blinded to patient allocation per arm following this review of pooled data, and therefore cannot specifically assert as to why or which patient cohorts are living longer.
The apparent increase in median overall survival could be attributed to many factors, including the potential for increased clinical benefit accorded by the active GPS arm, as we had seen in our earlier Phase II study with the same patient population, and or by the treatment landscape and potentially better care for the patients participating in our study receiving either GPS or best available therapy. Interim analysis is expected by the end of the year or early next.
While the Independent Data Monitoring Committee, the IDMC, will continue to review unblinded data at their scheduled ad hoc meetings, and as in the most recent IDMC meeting last month, the IDMC confirmed that there is no safety issue based on their review of the unblinded data and concluded that risk-benefit assessment of the data warrants the REGAL trial continuation with the refinements we implemented.
Another significant update for the REGAL study is that 3D Medicines, our licensed partner for the development and commercialization of GPS in Greater China, has agreed to participate in the trial through the inclusion of approximately 20 patients from the Greater China territory. This triggers a $13 million milestone payment to SELLAS, which we expect to receive during the first half of this year.
Furthermore, GPS can potentially reach the market in Greater China much earlier now than had been anticipated if REGAL meets its primary endpoint for efficacy and the Chinese regulatory authorities determine that the REGAL data is sufficient for approval in China. This would trigger additional regulatory and commercialization milestones and royalties for SELLAS, which is very exciting. I would also like to briefly comment on the GPS Keytruda combination study in ovarian cancer.
The Joint Development Committee of SELLAS and Merck will meet again to further assess the data from this study and, as I've said on previous occasions, we will also explore with other partners the most optimal path forward in the best interest of everyone and for this program. This is a really very exciting year for SELLAS. With our two promising assets, GPS and our highly selective CDK9 inhibitor, GFH009, progressing through clinical development.
With several near-term clinical milestones and potentially value-creating events for SELLAS, we are pleased to kick off the year with a discussion on our lead program, the GPS REGAL study. Before hearing from Dr. Jamy, it is my pleasure to introduce Dr. Dragan Cicic, Senior Vice President of Clinical Development at SELLAS. Dragan?
Thank you, Angelos. Let me provide a brief reminder about the study design and characteristics of the REGAL study before I hand it over to Dr. Jamy, who, as Angelos said, is one of our key partners in GPS development.
REGAL is a registrational Phase III randomized trial in acute myeloid leukemia patients in a second or later remission. Primary endpoint is overall survival. Patients are randomized 1-to-1 to either a GPS monotherapy arm or best available therapy arm, where best available therapy is defined as physician's choice of most commonly used drugs in any combination, at any dose level, and with any pathology that the physician deems best for the individual patient.
The best available therapy drugs are defined as venetoclax, hypomethylating agents, azacitidine and decitabine, and cytarabine. All patients in second or later remission are eligible in principle, except for the patients who received or are scheduled to receive a bone marrow transplant after their most recent remission. Exclusion of transplant patients has been made for statistical reasons.
However, pre-patients who previously received a transplant and relapsed after transplant are eligible for our trial, as those patients unfortunately have poor prognosis. In addition, randomization is subject to stratification, and the trial has 4 axes of stratification, namely presence and absence of minimal residual disease, duration of the first remission, less than 12 months or 12 months or more, cytogenetics, meaning unfavorable cytogenetics against all other types of cytogenetics, and status of the remission, i.e., complete remission versus complete remission with incomplete platelet recovery.
Keeping the balance with stratification is imperative given that the aforementioned factors can result in two-fold or even bigger differences in the expected survival. This is the reason why we have very carefully designed our REGAL study to reflect real patient issues and thus give GPS the highest probability of success. I will now hand the call over to Dr.
Jamy to put the REGAL study in the context of the most up-to-date approaches in the clinic. Dr. Omer Jamy is an Assistant Professor of Medicine in the Division of Hematology and Oncology at the University of Alabama at Birmingham, and Associate Scientist in Experimental Therapeutics at the O'Neal Comprehensive Cancer Center. He's the Principal Investigator on several clinical trials, including our Phase III REGAL trial. His main areas of interest include myeloid malignancies, acute leukemias, and allogeneic stem cell transplant. Dr. Jamy, please.
Thank you for the kind introduction, Dragan, and I'm really happy to be here today to talk to you guys about acute myeloid leukemia, allogeneic stem cell transplantation, and how the REGAL study is actually trying to help a really high-risk subset of patients with AML, where there's a truly unmet medical need. Before that, I'd just like to discuss about the progress we've made in AML over the past 10 to 15 years.
We've actually made significant advancements in trying to understand the biology of AML over the past 10 to 15 years. This mainly includes understanding cytogenetics and molecular abnormalities which drive this aggressive disease in a way which helps us stratify these patients into different risk categories so that we can actually tailor the treatment plan for individual patients.
I think this has given us an idea about what patients benefit from what kind of chemotherapy, what patients may benefit from allogeneic stem cell transplantation in first remission, and therefore, I think gives us a better sense of the overall picture for a patient with AML.
Whereas, this gain in we made significant gains in understanding the pathology of AML, over the past five to six years, I think we've also made progress in therapeutic advancements for AML. We have seen. Prior to 2017, there were actually, you could count the number of drugs approved for AML on just one hand.
In the past five or six years, we've seen several drugs being approved to treat patients with AML, both in the frontline setting as well as relapsed refractory AML. All of these drugs have been approved based on prolonging survival for our patients. The prolonging of survival has been exciting with some agents and has been modest with others, but at the end of the day, there has still been a survival benefit, and it is giving physicians more options to offer to our patients at different time points during their journey.
This, even with therapeutic advancements and seeing numerous drugs being approved, there are still areas where research needs to be done, research is being done, and these are areas of unmet medical need.
One of the areas which the REGAL study is highlighting is patients in second remission ineligible for one reason or the other to proceed to stem cell transplantation. The REGAL study is trying to prolong survival in this really high-risk subset of patients, which is truly impressive. Let me talk to you guys a little bit about relapsed refractory AML first, just to give you an idea about the importance of the study. Patients who have relapsed AML, which means that they've achieved remission at some point and then unfortunately their leukemia has relapsed.
Your goal as a physician is to get them into a second remission or beyond, depending on how many relapses they've had, right? Once a leukemia relapses, the leukemia sort of tells you that chemotherapy by itself is probably not sufficient for long-term disease control.
At that point, anyone who achieves second remission or beyond ideally should proceed to stem cell transplantation for the best possible outcome. I'm going to talk to you about transplant in a little bit as well, just sticking to the relapse refractory AML point, you can treat patients with relapse refractory AML with various chemotherapy regimens.
These could be intensive chemotherapy regimens, these could be less intensive chemotherapy regimens. In fact, at UAB, we did a study looking at our patients with relapse refractory AML treated with both intensive and less intensive therapies just to compare outcomes of both regimens. We found for most patients that outcomes are very similar. The interesting thing was that survival was prolonged for those patients that were able to make it to stem cell transplantation.
Over there, survival sort of was 1 or 2 years or beyond. Actually, patients who are unable to proceed to transplant after achieving remission though, so this is for patients who've achieved a second remission or beyond but are unable to proceed to transplant, their median overall survival, depending on what study you look at, is anywhere between 6 to 8 months. It's not the greatest. Really, that's why I think it is important to, as a, as a transplant physician and a leukemia physician, my goal is always to take these patients to transplant, But as I'll talk to you about transplant in a little bit, not everyone is eligible for transplantation.
We need chemotherapy regimens, maintenance regimens, or different strategies, be it maintenance with vaccines, which is what GPS is, to prolong survival for this patient population. Therefore, I think, I think if you're not able to go to transplant, that is an area where I think research needs to be done and is being done in the form of the REGAL study.
Let me explain to you a little bit about transplant and what the advancements have been and what the barriers are, so you get a little sense of why not everyone can proceed to transplant after achieving second remission, As a transplant physician, I'm also proud of the fact that we have completely refined the transplant process in the past few years.
we have a better understanding of patient selection for transplant. We've got a better understanding of donor selection. This is mainly because of not just finding good match unrelated donors, but being able to offer haploidentical stem cell transplantation to our patients, expanding the pool of patients to which we can offer a bone marrow transplant. We've definitely improved our supportive care techniques with infection prophylaxis and treatment. We've improved our graft versus host disease prophylaxis based on some recent late-breaking abstracts at ASH.
All just to say that transplant can be offered to more and more patients. The median age of someone with AML in the U.S. is around 68 years, and about 10, 15 years ago, offering a transplant to someone above the age of 60 was unheard of.
Nowadays we can offer a transplant to patients up to the age of 75, but I would say between the age of 70 and 75, you sort of cherry-pick your patients because there is still significant morbidity and mortality associated with stem cell transplantation despite these advances. Again, at our center, we've transplanted folks up to the age of 75 if every other criteria is met.
What are some of the barriers to transplant, ? Let's say, we can divide barriers into various categories, but if you have a patient above the age of 75, that may be a hard no at most centers, including ours.
The patient may have no other comorbidities, but age by itself just made them ineligible for transplantation, so you'd have to find ways to help prolong survival without transplanting these patients. What about younger patients? Younger patients may have other barriers, If you have a young patient who has a significant comorbidity burden and has a poor performance status, then the risk of transplant may outweigh the benefit of transplant,
When I talk about comorbidities, I don't mean well-controlled comorbidities like blood pressure, diabetes, hyperlipidemia. I mean comorbidities which can cause serious, seriously poor outcomes after transplant. These may include chronic kidney disease because it interacts with almost every medicine you need for a transplant to be successful. This could include COPD on oxygen. This could include congestive heart failure.
Serious problems which can occur because of the chemotherapy we've given to our patients, or these patients may have had these comorbidities prior to the diagnosis of AML as well. These can be legitimate barriers to transplantation. I've been obviously telling you how we've done a great job in finding donors, or expanding the donor pool for our patients, but even today, a lack of donor availability is a serious problem, and it is mainly a problem for racial and ethnic minorities.
Again, we are still trying to find donors for everyone, but sometimes, unfortunately, just not having a donor, is also a reason someone's unable to proceed to transplant. These are some medical reasons why someone may not be able to proceed to transplant.
You also have to look at the socioeconomic factors which factor in when deciding if someone can proceed to transplant. Transplant is perhaps, I would say, the most complex immunotherapy we have to offer to our patients. It is a completely life-changing event, more so than a diagnosis of AML. I think, Most transplant centers require people who live more than 60 miles from their center to completely pack up and move to the city for 3-4 months. That's not easy for everyone to do.
At least our center, and I think most centers, require 24/7 caregiver support for the first 3-4 months after the transplant for the transplant to be successful.
Again, many factors go into coordinating or planning a successful transplant for our patients. What, what I've discussed with you here, a few barriers which I see in my practice, because I will tell you this, that my goal for anyone with relapsed refractory AML is to take them to transplant.
I would try everything to make sure they go to transplant. But I still encounter many scenarios in which I'm unable to do so, as I've described to you just now. I think that is where the REGAL study comes in. I think, the REGAL study, as been discussed by Angelos and Dragan previously, is looking at patients in second remission or beyond, unable to proceed to transplant. The exact patient population I'm talking about.
A very high-risk population because these patients without transplant, honestly, and unfortunately, will not live for that long. We need to do everything we can to prolong survival in this high-risk subset. REGAL study is taking GPS, which is a vaccine designed against Wilms Tumor 1, which is expressed on leukemia cells.
The Phase II data, as has also been discussed, showed that the median overall survival of patients receiving GPS in a similar setting, was significantly prolonged, and at around 21 months, which is very fascinating for this high-risk population. What's the next step to do? The next step is to confirm these findings in a well-designed randomized Phase III study, which is what is being done over here.
you may have good phase two studies, but you'd always want to confirm the data in a randomized phase three. I think credit to the people designing the REGAL study, and we'll go over the clinical design in a little bit as well. Now we have a randomized phase three looking at GPS versus best available therapy.
Another thing I really like about this study is the multiple options in the best available therapy arm, which I think many phase threes would be. I mean, sometimes the control arm is not very appealing. I would say that being able to offer pretty much anything to patients in the control arm deserves credit as far as the design of the study is concerned.
After a very strict inclusion/exclusion criteria, which is very appropriate, I think enrolling patients on this study definitely it has the potential to help these patients based on the Phase II data. The randomization is 1-to-1 in the GPS arm versus the best available therapy arm. Is also stratified or along these axes, which I think is great actually. duration of response, as Dragan mentioned.
Duration of response means the time you reach your first remission and the time you relapse, the longer that duration is, the better your chances of achieving second remission or beyond. The better your survival, as opposed to someone who relapses very early.
Using that variable, along with measurable residual disease, which is a very important topic in AML these days, MRD positivity and negativity is impacting outcomes. Lastly, risk of disease, as I discussed with cytogenetics. It is taking all the right variables into account when stratifying patients between GPS and best available therapy.
We have been part of the study. We've enrolled several patients on the study. Based on the Phase II data, I liked the efficacy, but also the safety and the fact that there's potential to preserve quality of life while also prolonging survival, which is very important for our patients with AML.
we remain enthusiastic about the REGAL study and I think the fact that the blinded analysis shows that everyone on the study is doing well is great. The statistical modifications to change the number of events, for 80 for final and 60 for interim should ensure that the study completes in a timely manner. To me, I eagerly await, as I'm sure everyone else does on this call, the final results of the REGAL study.
I would be I think it would be If the study shows clinical meaningful statistically significant difference, I think it'd be a great option for a patient population where there's not a whole lot to offer.
with that, I'd like to end my presentation and hand it back to Dragan and Angelos. Thank you.
Thank you very much, Dr. Jamy. I think it's exciting from our perspective. I also want to thank you and your study team for participating in the trial. As you correctly pointed out, we're going after a patient population that's either unable or ineligible for transplantation, which still today, unfortunately, as you mentioned, relapse and die ordinarily within six, seven months or so.
Obviously, our hope is what we saw in the blinded data that is going to translate once we unblind the trial, that hopefully GPS is really the driver in survival benefit. With that, Tara, can we open it up for questions by our analysts first? Obviously we'll take questions by the written questions that participants have submitted that are REGAL relevant.
Yes. Thank you, Angelos. Our first verbal question comes from Li Watsek from Cantor Fitzgerald. Please go ahead, Lee.
Hey, good morning. Thank you for the presentation.
I got a couple questions for Dr. Jamy. Maybe first, can you give us a sense of what percentage of patients will be eligible for GPS treatment among the AML patients? The second is that given the treatment landscapehas evolved as you alluded to earlier. How do you think the prior therapies might impact how a patient responds to GPS? Can you also talk about what the potential impact might be on the phase three REGAL trial?
to answer your first question about who would be eligible for the REGAL study. I can't give you an exact percentage, but let me tell you what my thought process is, because I do both leukemia and stem cell transplantation, right? When I see a patient with AML, although there are some that may actually not need transplant, I don't tell them that. To me, there's no such thing as favorable-risk AML. It's a relative term, and I think 70%-80% of all AML patients at some point in their journey are going to require stem cell transplantation. I'm talking about first remission.
Let's say someone goes to transplant, they can relapse after transplant. Transplant doesn't guarantee that...
Transplant doesn't guarantee cure is the first thing. You have patients who are ineligible for transplant from the get-go in first remission, despite their disease being eligible for transplant, which means that they will relapse. Which means that if you get them into second remission again, they will again be ineligible for transplant unless by some miracle they become eligible, which would be unlikely. I think the challenge is getting patients into second remission. That is not easy.
Like once a leukemia relapses, if you get them into second remission, that is a challenge. Keeping them in remission is another challenge. I would say, you can, you may end up with. I can just talk from my personal experience as we've enrolled several patients.
You will have patients to go on this study as the, if you work closely with both the leukemia and the transplant team, you will definitely have patients to enroll on this study. That is my take on your first question. Your second question being the treatment landscape is changing for AML. That is correct. We have, as I mentioned, in the beginning, we've had, like, several drugs FDA-approved between 2017 and today in various spaces.
Like one of those, for example, one of those agents is venetoclax, which is approved for frontline therapy for AML. You've got several agents approved for relapsed refractory AML. If you keep on, if you look into the details, people who go into remission without transplant, these drugs are not very durable, I would say.
I don't think they shouldn't impact eligibility or enrollment for a study in my opinion, in a significant manner, honestly. I've forgotten your third question by now.
Yeah, but I think you answered it. I'm just curious what the potential impact might be for the phase three REGAL trial.
A potential impact of these drugs, you mean? Yeah.
Yeah.
Yeah. so it's, I may get too technical here, but you could. For example, I'm just going to give you an example. Again, you don't have to like, make much of it, but I use this study, for various purposes. if I have a patient who's like 85 years old in second remission on venetoclax-based therapy, which I think among the drugs that have been approved is probably, one of the more appealing ones. I sometimes, can think of it as a de-escalation because you are committing to lifelong therapy if you're not doing transplant.
I feel like even despite very interesting drugs being approved, there is still role for GPS for those patients as well.
I think if I can just, for 1 second, Lee, to add on to what Dr. Jamy just said. In our research that we have done, in the U.S., EU 5, and Japan only, once you funnel through the treatment landscape, that allows for about 10,000 patients or so that would be eligible in the CR2 maintenance phase. As very well, there's nothing approved in CR2 maintenance.
Remember, we're going after patients in second complete remission where nothing is approved. Even venetoclax and hypomethylate, as you heard from Dr. Jamy, but also previously from Levi Garraway, it's still in that 6, 7, 8 months timeframe. More and more drugs have gotten patients into remission.
Unfortunately, those ineligible or unable to get transplanted just don't do well, that's where we hope GPS will make a significant impact.
Great. Thank you.
Angelo, can I-.
Our next question comes from Jason McCarthy from Aegis. Please go ahead, Jason.
Sorry, my computer's being a little wonky. Thanks for taking the question. Can you help us understand a little bit about looking at the duration of the first remission and time to that first remission, and then time to second remission and that duration in terms of how that could impact the data? Are you screening and excluding based on some cutoff for time to first remission, or is it kind of all comers in second remission and you figure out the data after?
I think, Mondo, lead this off and then Dragan, please, chime in. Basically what we do, Jason, because we have one of the stratification factors is the how long patients were in remission in CR1. It's one of the stratification factors. Ordinarily, patients who in the first complete remission are somewhere between 3 to 9 months, for example, in the second remission, they will unfortunately relapse and die somewhere between 3 to 6 months. If they have a 12 months or more remission rate in CR1, then they may do about 6 to 9 months in CR2. Inevitably it's still bad, but it's one of the prognostic factors.
Again, it's a stratification that we have built in and for obvious reasons, because we don't want to have an imbalance that one arm may have better or worse prognostic factors, so it's well-balanced. That's one of the key points, absolutely, the duration of response in CR1. As I mentioned, it's one of the certification factors that we've carefully built into our Phase III REGAL trial.
Oh, sorry. Go ahead.
No, just a quick note. We do accept, as Angelos said, all the patients regardless of the duration of their first remission, but they're stratified so that we have the balance.
General rule of thumb, what Dr. Jamy can confirm that. The general rule of thumb is that the second remission is almost invariably much shorter than the first remission. As a rule of thumb, you could even say like a factor of 2. If somebody had the first remission of 12 months, the expected duration of second remission is 6 months, right? Patients who relapse within 9 months or 8 months or 6 months, we are looking at the expected second remission of just a couple of months or so.
But that's why we have to stratify these patients so carefully.
Is it possible that if you have a 2x survival increase in the pool data, you haven't seen anything that you're getting more patients that have had longer or more durable first complete remissions and second complete remissions impacting the total trial? Or do you have more patients that have more advanced disease, shorter initial remissions, and then shorter, obviously, second remission durations?
I think
Let me just.
That's why I'm asking you to read tea leaves. I'm not.
We don't really know because we are not looking at individual patient outcomes. However, I'll ask Dr. Jamy to give his take on this from what we know and what we understand. patients who had a very good first remission, very durable first remission, they generally have more options, they are more likely to be transplant eligible, they are more likely to have a curative option. Typically, as Dr. Jamy indicated, they are not going to be put on a trial, right? Again, that's speculative in the absence of actual data. I'd like Dr. Jamy.
Sorry, Dragan. Just to be clear to Jason's question, since we have not unblinded the trial, we don't have any input to number of patients who had longer or less than 6, 9, 12 months duration in the CR1. We will only know that once we're unblind it. Suffice it to say, because we have the stratification factor, it's very unlikely that there is an imbalance between the two arms, which again, I think is pertinent to your question. I want to make sure that I answer that directly and head on.
We don't have that unblinded data, obviously. Because there is a stratification and both arms are equally balanced, I do not foresee once we unblind that's going to have an impact either way.
What we do know is that we see about a 2x survival benefit. If we look back into the Phase II study, and again our trial design overall, again once we unblind we'll know. From what I think you have heard, obviously, and I think it also speaks to Dr. Jamy being excited with REGAL. We're also very hopeful once we unblind, we'll see the data that hopefully will provide additional treatment option to patients in need.
Great. Thank you for taking the questions.
Thank you for the questions, Jason. Our next question comes from Aydin Huseynov from Ladenburg. Please go ahead, Aydin.
Hi, everyone. Thank you for interesting discussion. A lot of questions were asked and answered, but I want to sort of build on the previously asked questions as well. I'm going to ask Dr. Omer Jamy. You mentioned that the expected survival in CR2 is 6 to 8 months. I just want to ask, is this sort of based on the previously published literature which we see like 5 years, 10 years ago, or this is from your sort of current experience? What is your estimation based on your experience, based on the patients that you've seen CR2, what is the longest survival you saw in CR2 in your practice?
Sure. Thanks. To answer the first part of your question, when we talk about that number of 6 to 7 months, I would just want to be clear, that is for patients who achieved second remission and are unable to proceed to transplant. Just because if you ask me what's the longest my patient with CR2 lives for, I would say very long time because I take them to transplant. I want you to just distinguish between these 2 features very carefully. Coming back to the first part.
Sorry, Dr. Jamy, which are not the REGAL patients. I just want to make it very clear.
Exactly. Exactly. Right. Right. Right. Right. I think that part has already been cleared, that REGAL is for transplant ineligible patients. The 6-8 months actually, let's just say, okay, that 6-8 months is also with recently approved agents. I'm just going to give you Phase III data which is out there. With FLT3, which doesn't go on the study with relapsed refractory, median survival is, like, 8 months, right? With IDH inhibitors, median survival is again 8-9 months. Again, these are targeted agents. With AZA-ven in relapsed refractory, its remission rate is high, 35%-40%, but they are not durable. Again, 6-8 months.
Again, you have to realize these are all, these studies are sometimes at different centers, there are biases, but you will not see a study of relapsed refractory prolonging survival to more than 12 months, in the absence of transplant is the starting point. It also depends on what is the risk of your leukemia, right?
What was the duration between your first remission and first relapse. Too many variables go into it, but to your question, that 6-8 months is in the context of recently approved drugs as well. I would not say it's any longer, with so many, drugs approved in the past 5-10 years.
In fact, it may have been shorter if you looked at it seven, eight years ago as compared to now.
Understood. Thank you. For the choice of best available therapy, what do you use, and how do you expect the choice of the best available therapy may affect the comparison with GPS?
That's a good choice. That's a good question. I really like the fact that best available therapy is open. You could restrict it to the, to the least impressive agent, and that would be. The criticism would be, "Well, why don't you allow for more potent agent?" I, de So I would definite... I usually encrou My personal practice, and I don't know if I can share that data. I'll ask that question if I can share what I usually do with Angelos and Dragan before letting what I usually do on this study about what my choice would be for best available therapy. Is that something I can share?
You can, yeah. That's fine. I think maybe Dr. Jamy to, before you do that, just to clarify that the choice of best available therapy was discussed and agreed upon with the FDA, both for ethical reasons and secondly also to assure a proper enrollment. Because as Dr. Jamy said, if we had put maybe 1 or 2 drugs that are just not used at all, Dr. Huseynov, it would have been very difficult to enroll to the trials. It was both for ethics and per agreement with the FDA, thirdly from a statistical perspective, it's still in the range that we know how how those drugs behave. Please go ahead, Dr. Jamy.
Sorry, Angelos. I mean, just Dr. Jamy, it's, I think that the best way to respond to this is, and I think that's what Ivan's asking really, is whether you would treat those patients with those drugs outside of the trial. If you were not doing the trial, with this what you would normally use in your practice?
Exactly. Yeah. I mean, I think the, I think you bring a very great discussion in general that the control arm of any good study should be what an investigator is going to use outside of the study. you hit the nail in the head, basically. Like, if the control arm was something that I would not have used if the study was not there, then that's a poorly designed study. All credit to the designer here of opening the best available therapy options. I personally use a Venetoclax-based combination for patients in second remission, basically.
Got it. Got it. Yeah. That's, that's very helpful. One question I want to ask, probably would be more related to Dragon, is: You mentioned the CR2, is the duration CR2 is sort of reduced by a factor of 2, compared to CR1. If we do sort of back calculation, that would mean, let's say like about 24 months for CR1, would that be sort of a reasonable expectation to have a CR1 of 24 months? Just sort of try to re-engineer this study.
Yeah. Yeah. Yeah. Again, we are not restricting this. However, in clinical practice, right, patients who have CR1 of 24 months are normally patients who are
Eligible for transplant in the second remission, patients who are eligible for more aggressive therapies and so on. We don't expect to see many of those patients in our trial.
Certainly not majority, certainly not half of the patients are. Again, we don't want to, and we cannot look at individual patients and their outcomes, but in this patient population, it would be highly unexpected, highly improbable to see this, any significant number of patients with good prognostic factors.
Understood. Understood. The last question I have about enrollment and sites. I think the press release mentioned that University of Alabama is one of the highest recruiting sites. What is the percentage of University of Alabama patients that you're recruiting compared to other sites?
Yeah, I think maybe, I can chime in here. I think two things, Dr. Huseynov. One is, as far as the other sites are concerned, I think many of our participants here on the call today will be pleased to hear that over the next 24, 48 hours, an updated revised ClinicalTrials.gov will be available. It's in the court of ClinicalTrials.gov to post it up. Secondly, as it relates to the question on enrollment we have from the beginning really. Let me step back for a second. We do not provide guidance on enrollment, and we've been consistent really with that since the beginning of the study.
It's important to remember that REGAL is an event-driven study, and our focus has been on guiding to events that trigger our interim and final analyses. I think today's call really provides a unique perspective from one of the highest enrolling sites in the U.S. and provides real-world evidence and the voice to the eagerness of our principal investigators enrolling the patients in the study to reach study endpoints in the hope of putting another weapon in clinicians' tool bags in the fight against the recurrence of cancer. More specifically, Dr. Huseynov, without getting into numbers we have sites both in the U.S. and Europe, obviously, and in India. with 3D Medicines coming on board, we'll be opening up in China as well.
It's pretty from a percentile perspective, they're certainly on the higher as well as some sites in Europe. It's difficult to put a percentage quite frankly. Dr. Jamy is not an outlier as it relates to enrollment, but we just wanted to make sure that one of the U.S. sites with a higher enrolling number of patients would participate today.
Got it. Okay. Thanks so much for taking the questions.
Thank you.
Thanks for the questions, Aidan. We'll now go to the written questions. The first one is, why are you doing the call today?
Well, firstly, we're extremely grateful for Dr. Jamy joining us today and to staff and institution, as I mentioned before, for participating in the REGAL study. It's something that study is so important to us as a company, to shareholders, but really to patients alike. We're very excited to hopefully ultimately provide an option to patients in dire need, their families and physicians. Dr. Jamy, again, provides a unique perspective as an expert hematologist with experience in the dire prognosis of patients in second remission and his enthusiasm for the potential of GPS to improve patients' outcomes.
Really his insight into the current AML landscape and how GPS could serve as an important treatment option in his arsenal and overall physician's arsenal for patients as he strives to prolong survival in this high unmet medical need. The objective of today's call was really to bring our shareholders and analysts along the REGAL journey, particularly after the recent refinements. As we heard today, the median overall survival in patients in second remission, unfortunately it's not something. As a study sponsor, ultimately, we all want patients to benefit. Unfortunately, outcome in second complete remission has not changed with drugs approved. We really hope that GPS will be a treatment option that can indeed increase survival benefit.
That's the reason why we decided to kick off the year with our lead program, which is the REGAL study.
Thank you, Angelos. Our final question today is, why do you not provide updates on the status of enrollment?
Yeah. Well, I think I alluded to that earlier, I believe it was with Dr. Huseynov's question. We do not provide guidance on enrollment as we have been consistent since the beginning of the study. It's an event-driven study, the interim analysis and the final analyses are the ones that will yield hopefully the outcomes that we all envision. Remember also, the Independent Data Monitoring Committee has scheduled an ad hoc meetings where they will be able to make decisions based on unblinded outcomes that we cannot obviously see. That's the reason we have not provided updates on enrollment.
Suffice it to say that we're very excited with the interim analysis that we expect forthcoming based on our calculations sometime by the end of the year. As I mentioned before, the Independent Data Monitoring Committee, in their toolbox, if you will, can meet ad hoc and make recommendations even sooner than that. As I said, we're very excited with what 2023 will bring for SELLAS on both GPS as well as our CDK9 inhibitor.
Great, thank you, Angelos. This concludes the question and answer session today. I'll now turn it back to you, Angelos, for closing remarks.
Yeah, I think the closing remarks, really firstly, I would like to thank everyone for listening in to our webinar this morning. I want to thank Dr. Jamy for his time this morning to talk about the AML landscape and CR2 in particular, and the REGAL study. If there's something I want everyone to walk away with, is the Phase II data, 21 versus 5.4.
The fact that there's nothing approved in the CR2 maintenance phase, which is where GPS is coming in. With our other asset, the GFH009, we can go earlier and then have GPS as a maintenance therapy, God willing, if we have positive data and we get approved. The fact that it's GPS, the REGAL trial is in patients ineligible or unable to bone marrow transplant.
I think that's a very key differentiator because transplanted patients, as Dr. Jamy alluded to, may benefit. Our study does not include those patients, and unfortunately, as I mentioned, those patients ordinarily, as we have heard now from clinicians within six to seven months or so. We're very hopeful that GPS will be a treatment option very soon to patients in need and to clinicians to provide them with additional options. Really thank you very much for everyone for listening in, and I wish you all a wonderful day ahead.