Full Show: A Vaccine to Extend Myeloma Remissions with Syed Abbas Ali, MD, Johns Hopkins
Syed Abbas Ali, MD
Johns Hopkins Medicine
Interview Date: October 16, 2020
Thanks to our episode sponsor
There are many therapies today for the treatment of multiple myeloma, but myeloma typically returns, requiring new therapy for the majority of patients. What can be done to extend remissions? While vaccines don't help eliminate heavy tumor burdens of myeloma, they can help the immune system continue to recognize its return to keep it under control. In this informative show Dr. Syed Abbas Ali of Johns Hopkins Medicine shares the GVAX vaccine that is now in Phase II clinical trials to be used following a stem cell transplant or other induction therapy. Patients must be currently on Revlimid, have no high risk features and have a specific MRD level of disease to join. Patients may have prior stem cell transplant (must be out a year from transplant) or not. The Phase I study data is now mature enough and the results look promising that this simple vaccine could dramatically lengthen time in remission for myeloma patients.
Dr. Ali on Myeloma Crowd Radio
Jenny: Welcome to today’s episode of Myeloma Crowd Radio, a show that connects patients with myeloma researchers. I’m your host, Jenny Ahlstrom. I’d like to thank our episode sponsor, Bristol Myers Squibb, for their support of Myeloma Crowd Radio and today’s program.
Now, before we get started on today's very interesting show, I have just a short announcement about recent updates inside of HealthTree. We now have over 7,800 people who are using HealthTree, and we've built a set of Myeloma Crowd Community forums that you can find inside the platform. They're organized by topic. We have new notifications now, so when someone wants to be your twin or someone comments on your forum posts, you'll be notified inside the HealthTree.
We're looking for better ways to extend your connections with one another. In the forums, we want you to be able to go back and find specific answers by topic instead of trying to scroll through sometimes what is an endless social media feed to find what you're looking for.
In the Twin Machine, we've also expanded those notifications so if you are trying to find somebody with similar genetics to you and your myeloma, you'll be able to issue a friend request basically, and then be able to chat back and forth and see those friend requests and accept them and see other people's acceptance of yours and those notifications.
We also have a new feature in the works in HealthTree that I'm going to not share completely. I'll keep you in suspense, but go in and enter your prior treatments and your side effects to get ready to use this new feature. I know you're going to love it. We also have a team ready at all times to help you enter information if you need help doing that. We give you electronic ways to do that yourself, or we can do that for you if you prefer.
Now, on to today's exciting program. Myeloma patients have heard a lot about maintenance therapy in the last decade, I would say, which is a really good way to extend remissions, and the majority of maintenance therapy today are immunomodulators and now some proteasome inhibitors or other drug classes like monoclonal antibodies are being considered and used in the myeloma clinic. So, once the tumor burden is dropped after treatment, what else can we do to keep myeloma from coming back?
In today's show, Dr. Syed Abbas Ali from Johns Hopkins Medicine will share a vaccine in development to try to sustain remissions following stem cell transplant. Dr. Ali, welcome to the program.
Dr. Ali: Thank you very much, Jenny, and thank you to the myeloma crowd and our audience for having me. Thank you.
Jenny: I'm super excited for our show today. Before we get started, let me introduce you just a little bit. Dr. Ali is a myeloma specialist and Assistant Professor of Oncology at the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins Medicine. Dr. Ali earned his MBBS degree at Agha Khan University. He completed his residency at UAMS in Arkansas and performed a fellowship oncology at the National Institute of Health.
He spent the last several years working on the vaccine for discussion today, and I've had several opportunities to share those results at major meetings like ASH and the International Myeloma Workshop meetings. His research extends to other immunotherapies like monoclonal antibodies, and he's performed significant research on CAR T-cell myeloma clinical trials, so, a wide range of immunotherapy type of clinical trials and background.
So, Dr. Ali, we're so excited to have you with us today.
Dr. Ali: Thank you, glad to be here.
Jenny: Maybe we want to just start very broadly, talking about how are vaccines used in myeloma care. I know there are some disease-prevention vaccines, like we're thinking about with COVID and things like that. This isn't necessarily to treat the myeloma itself, but to do something else, so, maybe just a broad background of how vaccines are used in cancer care and myeloma care in general.
Dr. Ali: Thank you very much for the excellent question. To give it a broad background, we're all I think, aware now that the myeloma landscape has really changed in the last 20 years. This is because of primarily the advent of proteasome inhibitors and then IMiDs and daratumumab and other immunotherapies. Things have really changed. What's also, as you were mentioning earlier, really changed the paradigm is people are getting transplant. Even with or without transplants, people are going on long-term suppressive maintenance therapy with Revlimid. What’s become apparent with all of this is that maybe what's going on to improve our outcomes is that we're getting deeper responses.
Now, into all of this mix, there are data that show that minimal residual disease testing, MRD testing, which are data that are still maturing and whether you do MRD testing by flow or NGS model, suggest that getting into an MRD negative state is a good place to be. It improves the progression-free survival outcomes. So, the question still remains, how do you approach patients that might be MRD positive, especially where they're either low degree of MRD or high degree of MRD? Because the basic paradigm for myeloma still remains is that the primary concern for most patients over a long enough timeline is that people will relapse into this entire context.
We have the whole world of cancer vaccines. Cancer vaccines have been, in real terms, have been around for a long time, since the late 1800s when people tried giving bits and pieces of bacteria like streptococcus to patients with sarcomas and saw a response. The basis of vaccines or cancer vaccines is pretty much the same across the board, which is to amplify the tumor-specific immune response. You want to recruit T-cells or other immune cells to target your cancer. These have been tested in various malignancies, starting with the solid tumors, specially solid tumors like melanoma, which are immunogenic cancers. But you know what? We saw responses, but it isn't quite the slam dunk that we thought it would be, whether it's for solid tumors or for myeloma, at least not yet. There are many reasons why that could be.
There are FDA-approved vaccines, let's say, for prostate cancer, but not too many for any other malignancy. When you look at cancers in general, or the myeloma space, when you're trying to reduce or rather produce an immune response, then you need to try and target something. Maybe your vaccines are used to target a specific set of antigens. These are often tumor-associated antigens. How you use those, how you modulate those affects how your vaccines work. Having an immune adjuvant, a drug that helps poke the bear, poke the immune system to wake up, this is cancer, this is myeloma; that's very useful. How you use that, what you use makes a difference to how your cancer vaccine works.
Having other drugs to help jack up the immune system, for lack of a better word, drugs like Revlimid, for instance, so, checkpoint inhibitors; this also makes a difference to how your cancer vaccine or myeloma vaccine might work. Really, the other thing that's important about context is, where are you designing your myeloma vaccine for? Is this something -- or your cancer vaccine for -- is this something that you're going to try and use to reduce the amount of tumor burden, starting with a large tumor burden?
Studies have shown, for various cancers, that you can make a vaccine and you will get it to kill cancer cells, but there are two aspects to this. Reducing tumor burden, especially when there's a large amount of tumor burden, is not as easy. It's easier said than done, which shows that maybe, especially in the heme malignancy space and the myeloma space data that we have that I'll be talking about as we talk a little bit more about GVAX, and others, have shown that perhaps the best setting for these vaccines, especially in diseases like myeloma, is to try and keep things suppressed, perhaps to prevent a relapse, perhaps to prevent a transition of disease, let's say, from MGUS to smoldering or smoldering to active multiple myeloma, or perhaps to maintain an immunosurveillance-type situation, where, with myeloma, for instance, you're not eradicating the disease entirely, but because you've improved your immunosurveillance by training the immune system to recognize the myeloma via the vaccine, you are keeping a lid on the myeloma and keeping things from getting any worse.
Jenny: That's so interesting because you're not necessarily saying, okay, we're going to use a vaccine to treat the actual myeloma. You can use other drugs to do that, and there are a lot of those, even stem cell transplant, older chemotherapies like that but, yes I think that's great to think about how to use that in such a different way.
Dr. Ali: Absolutely. I think an aspect of vaccines that needs to be borne in mind is that maybe, and these are things that are still in development, that maybe one of the best uses is to keep a prolonged suppressive state and with a series of shots that you have to take it, maybe longer intermittent intervals, and that this spares you from getting the big, whopping chemotherapy, but at the same time, makes it so that the immune system keeps a check on things. And the right context for it, the right combination partners for it, whether you use Revlimid, checkpoint inhibitors, the right construct; all of these things are the things that are under development in various trials and with our own trial.
Jenny: Great. Well, do you want to talk first about the difference between allo versus auto vaccines in myeloma and then we'll talk about the other types of vaccines before we jump into the GVAX vaccine?
Dr. Ali: Absolutely. It's another excellent question. The dendritic cells, which you guys may have read about, these are professional antigen presenting cells. These were identified and described back in the ‘70s, and people have been trying to harness dendritic cells and leverage the immune system in general, to produce a response against the cancer. There are combined vaccines, whether for solid tumor or for myeloma, where you use a cell-based vaccine, and you can do something like, say, take a dendritic cell vaccine -- take a dendritic cell from a person and combine it with a tumor cell from that person, a dead tumor cell from that person, and use this as a means to give this back to the patient after culturing with different immune adjuvants, and use this as a means to train the immune system. So the dendritic cells take the bits and pieces of a tumor cell and go to the immune system. Hey, by the way, look here, this is myeloma, and we need to learn how to learn how to kill this.
The advantage, amongst others, perhaps of using autologous sources of this is that, this is as personal as it gets, right? When you say personalized medicine, you bring your own cells to mount an immune response, then these are the cells that your immune system sees every day. It recognizes these, or it sees these, or it’s been exposed to these. That perhaps is certainly one advantage of saying that, look, let's use autologous cells. These are antigens that our immune system is trained or at least has been exposed to and might recognize. That's one advantage of using autologous cells. These are self-antigens.
This, you can compare with allogeneic, but before you do that, the thing to bear in mind is that the immune system, myeloma and cancer in general, is very suppressive of the immune system. Myeloma recruits various immune cells like myeloid-derived suppressor cells. These have suppressor in their name and what they do is, in turn, they go and suppress the parts, the bits and pieces of the immune system, the business end, and keep those from attacking the myeloma. That's what myeloma does. It also does things like up-regulating checkpoint inhibitor molecules, or checkpoint molecules rather, and the PD-1/PD-L1 axis. These, in turn, shut off the immune system. The immune system is exposed to the myeloma, and the immune system tries to kill the myeloma. So, for patients with cancer or with myeloma, the immune system might become tolerized to the presence of the cancer. That is a thought that you have to have in mind that when you throw the same antigens at the same immune system, perhaps is already tolerant of those, and you may not get the sort of response that you want.
Now, when you take allogeneic sources of vaccines for myeloma, what you're essentially doing is saying that, look, I'm going to take cells from somewhere else. That sort of makes it easy because there are myeloma cell lines that are out there that have been derived years ago from patients that had very aggressive myeloma. These are myeloma cell lines that have various myeloma antigens in them. The cells are fairly deranged and used to be fairly aggressive, and so they have a large repertoire of antigens that an immune system can look at and recognize. When you kill these allogeneic cells and then give them what's the remnants and the bits and pieces of these myeloma cell lines to patients, then maybe what you're doing is, you're saying that, hey, look, this is what myeloma looks like.
These, because they're allogeneic and not autologous, are different enough that perhaps, the immune system is not as tolerized to them. When you give this in a well-designed construct, with, let's say, GM-CSF, or let's say with Revlimid, or let's say with checkpoint inhibitors or some other construct; maybe what you're doing is essentially giving the immune system an opportunity to recognize cells that are myeloma, but different enough that it might actually do something about it.
Jenny: Okay, that makes a lot of sense between the auto and allo, and I can see advantages for both. That's really interesting. The allo is like an off-the-shelf. You could have it prepared and doesn't maybe need to be personalized. Some may be a little more available too, in certain situations, like CAR-T.
Dr. Ali: Absolutely. Allo cell lines are readily available. They’re out there. The process of taking auto cells, manufacturing them, purifying them or doing whatever you need to do to process them to reintroduce; it makes it easier because you bypass that whole process. Maybe, again, the cells are different enough. When you think about allogeneic stem cell transplant for myeloma, that's an extreme form of the same idea because what you're saying is, hey, this old immune system, it works for other things, but really just completely misses the myeloma. Why don't we change out the immune system entirely and give you a new immune system from a donor? That is an extreme form of this, which is, you change out the whole immune system. So, giving the immune system new things to recognize is occasionally a nice thing for getting a response.
Jenny: I could see the advantage of that. You talked about the dendritic vaccines as being this auto idea. Are there other vaccines that are in process in myeloma, and even into the GVAX vaccine?
Dr. Ali: Absolutely. It's interesting, there's a lot of work being done in the solid tumor space in particular, as well as in the myeloma space in vaccines. We both mentioned the dendritic cell vaccines, and these are really very, very interesting. There's been a lot of work done by David Avigan’s group in Boston. It's a very interesting concept where you take these dendritic cells, you fuse them. Dendritic cells evoke a broad anti-tumor response when you combine them with tumor cells, which are your source of antigens, which are your target rich environment. Then you culture these GM-CSF. I keep mentioning GM-CSF. I'm just going to talk about that very quickly.
Jenny:. Yes, explain that.
Dr. Ali: GM-CSF shows up in a lot of different contexts as an immunoadjuvant. When I mentioned about poking the bear to wake it up, GM-CSF is a means of poking the bear and getting it to wake up and recognize the cancer. What it does is, it has sort of a stimulatory effect on CD4+ T-cells and CD8+ positive T-cells, as well as dendritic cells. So, when you give people GM-CSF, either locally or more systemically, it primes the immune system to be able to respond to something. When you cook, or culture, rather, cells like dendritic cells plus tumor cells with GM-CSF, then that whole environment is primed for the immune system to get up and recognize targets and to monitor subsequent immune response. This is how it comes to be used in a bunch of different vaccine trials, as well as other trials for myeloma and other malignancies.
David Avigan’s group, they published some really interesting and provocative data where they had initial responses with this construct in myeloma patients and then they combined this with auto transplant, in addition with Revlimid, with or without vaccine. I think this is a BMT CTN trial. I think it enrolled about 200-plus patients, and they saw some very tumor-specific T-cell responses and deepening of responses that you wouldn't otherwise expect after transplant. So, one place that the dendritic cell vaccines are being used is, the next natural step for this is to see, hey, why don't we try and find a different combination partner? Let's see if we can combine this with checkpoint inhibitor and if that gives us a better response or a deeper response because checkpoint inhibitors essentially take the brakes off the immune system. These trial data are these links for the trials are available on clinicaltrials.gov.
Other interesting trials that have been performed, really very interesting, there was a trial of construct, a multi-peptide construct called PVX-410 that was used especially in the smoldering myeloma setting. Now this is a very nice and elegant concept, to try and nip it all in the bud, get it under control, and train the immune system to realize that, look, you can't let this get out of hand. Because there are data that show we're still trying to figure out why people turn from MGUS to smoldering, there's aspects of clonal heterogeneity and so on and so forth, and why people go from smoldering to active myeloma. We're trying to find out where these transitions actually happen. One of the things that is involved is that aspects of immune surveillance change, and the immune system becomes more tolerized, or these plasma cells evade the immune system. So, maybe if you get in there and leverage the immune system before that actually happens, you have a better shot at keeping the myeloma under control for extended periods.
Ajay Nooka and colleagues published a very nice study. I think the paper came out or an abstract of this came out perhaps in 2018. What they did was they took these multiple myeloma antigens, CD138, which many people may have heard of, and something called Xbox protein 1, and SLAMF7, I believe, and turned this into a multi-peptide vaccine. Peptides are bits and pieces of molecules and proteins, and when there are enough of them or in a particular conformation, these can excite the immune system into going, whoops, I think something is there.
So, the rationale was that if you take these vaccines or these peptides which are HLA-A2-restricted, and combine them perhaps with Revlimid and give them to myeloma patients or smoldering myeloma patients with moderate or high risk of transformation, then perhaps you will see myeloma-specific immune response. Lo and behold, they saw that, yes, you did have myeloma-specific T-cells and enhanced T-cell response, especially in combination with Revlimid. When you give people this vaccine, the T-cells ended up producing interferon gamma, which, as we know, is this potent cytokine, that activates the whole immune system.
There are other aspects of looking into what other vaccines, strategies can be used. People have tried doing very interesting things like giving anti-idiotype vaccines. What they do is they put a genetic stem cell transplant, but what they actually do is take bits and pieces of the myeloma proteins flying around in myeloma patient’s blood. They make a vaccine out of that, give these to the donor of those alginate stem cells, and then give you the allogeneic stem cell transplant, with the thought process that the immunity will piggyback with that. That's a very interesting concept I’m certain is going to be developed further.
The dendritic cell vaccine is being used in an earlier setting, maybe even MGUS rather than smoldering myeloma. There is at least one trial out there, although I'm not sure if it's necessarily recruiting. There are even more ways to think about this. If what we're trying to do is wake up T-cells and grow T-cells, maybe combination strategies. I've done a lot of work in CAR T-cells for targeting BCMA for multiple myeloma, even strategies where you try and combine vaccines with anti-BCMA CAR T-cells. Because those are T-cells and when T-cells wake up, they tend to wake up other T-cells as well.
So, doing all of these combination therapies at the same time, maybe another avenue to explore that those anti-BCMA CAR T-cells might help you kill off the bulk of a tumor and then you have the vaccine that's back there that is now all woken up and activated by the immune system to keep a lid on things after the CAR T-cells have done their work. So, very interesting times and lots of avenues that are being explored in this setting.
Jenny: It's just fascinating, what's happening, and the work is just so astounding. If we had to have a cancer, this is a good one to have, with all the development that's being done. It's amazing. Do you want to give us an idea of just the history of this GVAX vaccine and then how it works?
Dr. Ali: So, GVAX is a very interesting construct. The gene in GVAX is GM-CSF, that’s aforementioned GM-CSF. The places where it was really studied and has been extensively studied is actually a lot of solid tumors, breast cancer, colorectal cancer, even pancreatic cancer in particular, a big study out of Hopkins, as well as diseases like CML, chronic myeloid leukemia.
So, what you do is you say that, look, I'm going to take some tumor cells, or I'm going to take another cell. I'm going to genetically modify these to secrete GM-CSF, so I don't need to give people injections of GM-CSF or give GM -CSF externally. I'm going to put in some tumor cells in there. I'm going to culture this all and put it in a syringe and make a vaccine out of it. When I give these to my patients, I can take pretty much bits and pieces of whatever cancer I want, pancreatic cancer, breast cancer, CML. By giving this immunoadjuvant at the same time, I give this to my patients and I see interesting responses. I see the T-cells wake up. I see cancer-specific immune responses, and maybe even some long-term T-cells that are in the system, or maybe even years later.
The larger questions then become, hey, how can I make this even better in certain settings? That's where Revlimid, in particular, comes in, in the myeloma setting. In excellent work done by Kim Noonan and Ivan Borrello, here at Johns Hopkins, they showed that what you can do is when you use Revlimid, Revlimid has a very potent effect. It’s called an immunomodulatory for a reason. It has a very potent effect on the immune system. It activates NK cells. It activates T-cells. It reduces regulatory components of the immune system like regulatory T-cells, so, in a roundabout fashion, reduces the brakes on the immune system, aside from directly targeting myeloma cells as well. So, it makes for a favorable immune environment.
Kim Noonan and Ivan Borrello showed in a very nice paper in 2012, that if you give Revlimid to patients with myeloma and you give them a pneumonia vaccine, then the pneumonia vaccine immune response is actually better. In fact, there are certain aspects of the myeloma-specific immune response that become a little bit better as well. So, these are really interesting and striking data and underscored how Revlimid is like, often, the spoonful of sugar that makes all the other medicine go down. I like using that phrase because it really improves the immune environment.
There was a follow-up study that Ivan Borrello conducted, which is the first GVAX trial. This is a very interesting study. What Ivan did was take patients, a total of 15 patients who had multiple myeloma. No one had a high-risk multiple myeloma. All the patients had low risk multiple myeloma, who were not in complete remission, but had a near-complete remission. The definition for that at the time was not having an M spike, but being immunofixation positive.
The vaccine consisted of a cell line called K562, which makes the GM-CSF, and myeloma cell lines called H929 and U266, which were irradiated, so they died. You’re irradiating them so you don’t get people live myeloma cells. We’re radiating them so that when you kill the myeloma cells, they break up, and all their bits and pieces go flying around so that they hit immune cells, and immune cells go, what's this? The goal of this was to see, look, can we, first, let's make sure that this is something that's safe to use; and can we use this to convert people into, say, a complete remission and eradicate what's left of the residual myeloma?
Now, out of these 15 patients, only five had had transplant, but patients had between one and four lines of treatment, and everyone had to be taking Revlimid, and the pneumonia vaccine was given with this at the same time. So, interesting things. First thing that they saw was that when you gave this vaccine construct to patients with myeloma, nothing really bad happened. There were no dose-limiting toxicities, no grade three toxicities. Patients could have a grade one toxicity where, if they got an injection, they may have complained of burning and pruritus. This was grade one, at worst, and resolved in pretty much everybody.
These vaccines were administered for a total of four doses, along with Revlimid, so, at month 1, 2, 3, and then six. What we saw was that, out of 15 patients -- and this paper has been submitted for publication on the updated results -- out of 15 patients, there were eight that went into a complete remission from having been in a near-complete remission, and the median time to getting there was a little over 11-and-a-half months. So, it's not something that happened immediately, but over time what you saw was this deepening of the response. When you put this in percentage terms, there’s a 52% conversion rate.
Jenny: Wow, that's really high.
Dr. Ali: When you look at this year’s out that we are now, you see that only six of those 15 had any evidence of progression, which is defined as having an M protein of more than 0.5 or more than 100 milligrams per liter when you're looking at the light chains.
What's interesting is that there are some patients who have had evidence of disease with variable amounts of M protein just a little bit beyond the near-complete remission that has shown up but still show no evidence of progression. There's disease there. You can see it in the blood, but well beyond the median PFS that you would expect, these people have remained in remission quite a bit from where you are. So, from the diagnosis, this median, the median follow-up at 6.9 years and 5.2 years on the trial, when you look at patients who are responding, the median PFS from enrollment could not really be estimated. That was really very striking to us.
Other things that were really very striking is that when Ivan in the lab and our group in the lab did minimal residual disease testing by next gen sequencing on seven patients where we had the samples that were available, what we saw is that there was a difference between having lots of MRD, maybe at 1x10-1, there was an arbitrary cutoff, but having MRD less than that, versus that level or more, was a predictor for how high you would go towards progression. So, if you had a lot of MRD then, as is expected, maybe you get a more rapid progression; but if you have low levels of MRD, then if you get the vaccine, your median progression-free survival was somewhere around 84 months.
Jenny: That’s long.
Dr. Ali: We're saying is that, in lower amounts of MRD. The arbitrary number that was said in the lab was actually very high amounts of MRD, but for people with lower or moderate amounts of MRD, what you were seeing was that there was a prolonged PFS in those lower levels.
Other interesting things that came out, when you look at the T-cell receptors to see if T-cells are expanding both in the blood and the bone marrow, you saw that, yes, they had expanded. When you looked at those T-cells to see if they were producing more interferon gamma, they were definitely doing that, and they were all these, what we call polyfunctional T-cells. When you look at these T-cells to see if they had a myeloma-specific phenotype, that was very much the case. These T-cells were myeloma-specific. They had expanded both in the blood and in the bone marrow.
In a number of these patients, what you saw is that, two patients in particular, where we had these long term samples, we saw that there was persistent vaccine-specific immune cells, up to seven years after dependence of any detectable disease. What that meant was that, look, we are reaching this, what we considered to be a form of immune equilibrium that, hey, this detectable disease or M spike showed up a while ago, however, these long term samples tell us there's a persistent vaccine-specific immune response. Our thought was that maybe why this was happening is that over all these years, the vaccine was maintaining an immune equilibrium, even though there was evidence of myeloma that was there.
There were other interesting things. You found T-cells in compartments -- tissue-resident T-cells, we call them -- that, again, are associated with longer term control of underlying disease process. Based on these data, we moved onto the phase two trial, which is what I'm leading, and what, at least part of this talk is about
Jenny: Oh, yes, for sure. The phase one, when did that start? Because that was a while ago, right?
Dr. Ali: That was a while ago. The study actually came online, back in 2011, and patients accrued over the next several years, or actually the next couple of years. The study has not been accruing patient for a good long time now. The correlators were studied extensively in the lab. When these progression-free survival just kept getting better, we thought, well, let's move this onto the larger randomized, controlled phase two study which is where we are now.
Jenny: So, you addressed safety, and you thought about dosing. What you said, I just want to emphasize it, because if you're saying persistent responses after seven years, and you only gave the doses after 1, 2, 3, and 6 months, in the phase one trial; I just think that's really remarkable, to have that long of a persistent response. You're looking at those T cells and seeing how they're continuing to respond, even seven years out, with no booster shots, basically.
Dr. Ali: Exactly, which is, as you say, very striking.
Jenny: Yes, it’s remarkable.
Dr. Ali: The cells are there. They’re demonstratively, which the paper will, once it's published, these figures will all be there, will demonstratively show that these are myeloma-specific, vaccine-specific immune responses. So, when we think about the fact that this happened with just four doses, as you say, then in the newer study, what’s built in there are booster shots on an annual basis for a couple of years, following the initial set of vaccines.
Jenny: Well, let's talk about this phase two trial. Maybe you can explain who can join, what are you looking for, how long the study is, how many patients you're looking for in the trial, and just all the details about the trial.
Dr. Ali: Thank you. So, the study is, it's a three-armed study. It's a randomized, placebo-controlled trial, and patients who are good candidates for the trial are patients who do not have a high-risk myeloma and have a myeloma that is under good control. They can be in a complete remission, or they can be in what used to be called a near-complete remission and now, most of the time, fits the definition of VGPR, but they have to be MRD-positive. Now, they have to be MRD-positive at a certain threshold.
Data from IFM/DFCI 2009, the transplant studies and many other studies showed that different levels of MRD, the persistence of MRD, give you different degrees of progression-free survival. These data from the IFM/DFCI trial are specific to the trial, but this principle is demonstrated in other settings as well, in other trials. So, we wanted to see and make sure that what we were doing was making a difference, both, scientifically in terms of learning, but especially to our patients with MRD that wasn't too high and not too low, just like Goldilocks’ porridge, not too much, not too little.
Dr. Ali: So you have to have MRD positivity at a level of 10-4, by adaptive clonoSEQ next generation sequencing. As our audience may know, adaptive clonoSEQ is an FDA-approved test for myeloma for looking at levels of MRD. Unfortunately, patients do come, who consent onto the trial sometimes, we find that their myeloma is in complete remission. We do the MRD testing, and they have, let's say, single digit copies, one or two or three copies. So, yes, technically, the MRD is there, but it doesn't meet the cutoff for the trial. More importantly, having that little MRD is also not a bad place to be. Patients who have 10-4 four or higher, that's 100 copies or more on your clonoSEQ reports, are the population that is really targeted.
Patients can have had a prior transplant. You don't have to have had a transplant. You're certainly allowed to have a transplant. If you had a transplant then you have to be at least a year out from the transplant. If you haven't had a transplant then, obviously, the requirement isn't there. Everybody needs to be on Revlimid and to be able to tolerate Revlimid. The reasons for this, that I've described before, Revlimid is what makes the immune environment favorable to this sort of vaccine.
Others requirements to be on the trial, which I forget if I mentioned, is that can't have high risk disease, so can't have a deletion 17p or a gain of 1q. These are all defined in the protocol. You need to have reasonable organ function. I don't have an age limit. If you've got a creatinine of 10, which is not all that common, but that puts you out of the range for the trial. Most people will be able to qualify the entry criteria, otherwise, in terms of overall function and organ function are not all that strict. We are looking to enroll exactly 56 patients.
What happened was that we developed the trial over a period of time, finally got all the funding that we needed and sorted out. We enrolled two people on the trial. The moment we did that and started their vaccines, COVID hit. So, we were on hiatus for seven months, and then we resumed again in September. Since September or in the last five to six weeks, we've enrolled five patients and are rapidly accruing additional patients as well. We hope to hit -- actually, we hope that we'll be able to recruit a whole number of patients within the next few months and get to our target fairly quickly.
The trial, as I mentioned, itself is a randomized placebo-controlled trial, and there are three arms. Everyone on each of these arms gets Revlimid. One arm will get Revlimid as well as Prevnar, which is a pneumonia vaccine. Part of the reason for this is because the prior trial used pneumonia vaccine, and we want to make sure that if this is a combination effect, that we don't miss it; and if this due to Prevnar as well, then we have an arm that excludes Prevnar. So, there's GVAX, Prevnar and Revlimid. The next arm, you get GVAX, and placebo and Revlimid; and in the final arm, you get a placebo and a placebo and Revlimid.
When I look at this whole thing, in my mind, what I see is that the good thing is nobody misses out on their standard of care. Everybody gets Revlimid, which is the standard of care in most maintenance settings, whether after transplant or when patients are done with their initial induction, even. At least two-thirds of people will get the GVAX vaccine, and we also answer the question of, how much input do you have from the pneumonia component? Does it also poke the bear enough to make a difference, or is it just a bystander in there? This will help us see in the long run that when we hope to take this vaccine, hopefully one day, to a point where we can get it registered and available to our patients, if the data hold up, as per the preliminary data, then we know exactly what sort of combination to use this in, best.
Jenny: So, patients cannot have a measurable M protein, right, but they have to be MRD-positive. That's like one cell in 10,000 cells, right? Is that right? 10-4? Instead of 100 copies.
Dr. Ali: Yes. When you're looking at, if that's one in 10,000 exactly or when you are looking at the report, the way the report by adaptive clonoSEQ is given, is given per million copies; and per million copies, we want 100 copies or more.
Jenny: Okay, that makes sense, but no measurable protein on your M protein tests. Then on the dose of Revlimid, if you have to be on Revlimid, can they be on any dose, or is there a particular dose that you have to be on and tolerating?
Dr. Ali: Most patients who received the Revlimid on the original trial, tended to be on 15 to 25 milligrams, and we had a lot of time meditating on what would be an optimal dose. The thing is, there's not a hard and fast rule that says that the immunomodulatory effect of Revlimid kicks in at X, Y, or Z. The way the trial is designed is that the protocol is not particularly stringent about what dose of Revlimid you come in on. However, you are allowed dose reductions, but you're not allowed dose escalations. So, if somebody comes in on five or 10 milligrams, they're not going to be going up to 10 or 15 milligrams because the only instance in which that would happen, potentially, is if things are moving along. If that's the case, we don't necessarily want to use the Revlimid to do suppress the myeloma.
The goal is to try and get the vaccine to suppress the myeloma. Although that also isn't strictly written into the protocol, by and large, the dose of Revlimid that you come on, is the dose you're going to stay on. Or if it's a high-enough dose, then it's a dose that can be reduced if patients run into problems. Occasionally, as you know, people will have side effects from Revlimid, especially after transplant. These include things like fatigue, or rash, or diarrhea, and so on and so forth. So, there's a little bit of room to maneuver in there.
Jenny: Once you get the dosing -- what is the dosing of actual vaccine in this phase two trial?
Dr. Ali: This is a phase two study in the sense that we have a standard flat dose for the vaccine so that there is no dose adjustment, up or down.
Jenny: I mean, frequency, I guess. In any other trial, you said 1, 2, 3, and 6 months. This trial, it's at what time points?
Dr. Ali: It's still 1, 2, 3 and 6 months. There's a bone marrow biopsy to begin with, a bone marrow biopsy at six months, and then an annual bone marrow biopsy. There's an annual vaccine booster. Going back to our comments that you and I were just sharing a little while ago, that we got a response to that just four doses, so we thought, if we give people annual boosters for the next couple of years, then we will even potentiate the response even further. So, there's going to be a total of seven doses of vaccine for the life of the trial.
Jenny: Okay. It's only happening at Johns Hopkins, right?
Dr. Ali: At this time, it is only happening at Johns Hopkins. I anticipate that our data will be both, in terms of the immune repertoire, the changes to the immune repertoire that we expect to see and without deeper MRD responses, I expect that our data will be striking in the months and years to come, so we hope to extend this to multiple centers as you develop more data.
Jenny: As we look at the landscape of myeloma, it's interesting that you're using transplant patients and non-transplant patients, so it doesn't really matter what type of prior therapy you've had or how many lines of therapy you've had, right? The other studies had one to four lines. So…
Dr. Ali: Yes, absolutely. Go ahead.
Jenny: Is there any expected prior lines of therapy for this phase two trial that you're looking for?
Dr. Ali: Once again, the trial, the protocol does not make a distinction with the number of prior lines of therapy that you had. The protocol does require and the study does require that if you've had a transplant, you be at least a year out. Part of this is because we think that it's reasonably safe to say that once you're a year out from the transplant, then the immune environment is kind of settled back to where it was before. There's nothing really unexpected that's going on, and it's okay to give the vaccine in that setting.
We can take patients that have a low-risk myeloma that is newly diagnosed and they’ve never had a relapse. Or we can actually take patients who have low risk myeloma that is not newly diagnosed and have had a relapse in the past. I don't have any specific requirements for X number of lines of treatment. If patients come to me in a situation where, if I find somebody, for instance, who has had 15 lines of treatment, I'm throwing a random number out there, but still clearly a low risk myeloma, have always had a low risk myeloma which occasionally flares up and requires them to go on treatment; then I will sit down and consider whether this patient can actually enroll on this trial, if they meet all the other criteria.
Athe beginning of the talk, I talked about how MRD testing and getting deeper responses, and as a trial endpoint, MRD is being explored more and more there. At the same time, every myeloma doctor will tell you that, look, I've got a patient that's been around or several patients that have been around since the ‘90s. I can't get the myeloma to go away entirely. If there’s an immune equilibrium that's been reached, and maybe that's true for patients that have these slow relapses over long periods of time. I have a patient that I have referenced to some of my other patients who come here, that I tell them about, who was diagnosed with myeloma in the late ‘90s, got some chemo in the early 2000s, said, “Look, this really isn't for me,” and shows up once a year, and always has a little bit of M protein in the blood, has not had any evidence of progression since that time, and we think has managed to reach a state of immune equilibrium and maybe been knocked back into an MGUS sort of state. So, these things are possible, even when you have had many lines of treatment. We're more than willing to look at patients that meet the broad criteria to see if this is appropriate for them to go forward.
Jenny: Right. You're getting booster shots at the facility, but it's not really that intrusive in terms of like coming to the clinic or anything like that. So, it seems like an easy study to join.
Dr. Ali: Absolutely. When you when you think about it, what's sort of missed in the myeloma world in general is, our median age of diagnosis is 69. Only 15% of our patients are under 45. Fully a third of myeloma patients are over the age of 75. I get transplant. I'm a big fan of transplant. I trained at the University of Arkansas, and I was at the Myeloma Institute there for three and a half years, with Dr. Barlogie. I'm a big believer in transplant, but there are certain settings where, especially for some patients, where you might want to think outside the box and say, hey, look, what else can I do to help bring this myeloma under better control for a longer period of time, that doesn't put my patient through a bunch of hoops that is sort of low maintenance, not particularly toxic?
I think what we've seen with the study so far is that the vaccine is very well-tolerated, that there are excellent data that suggests that it works, in the previous study that I described that is in the process of being published, and that coming in once a year to get a booster shot after you've had initial series of shots is fairly low burden. It's certainly easier than, let's say, coming in weekly for any sort of infusion, or every other week or even once a month for any sort of infusion.
Jenny: Well, completely, and if it's helping you get persistent T-cell responses for many years, you're almost up to a decade in your first study, then that's something that's really awesome for patients. I wanted to ask a question about the checkpoint inhibitors because you mentioned them a couple times in the show. How do you see that working together with -- I think everybody in the myeloma world got kind of nervous about checkpoint inhibitors when they were combined with Revlimid in some of the early studies, and those studies were shut down. How do you use them, because you're using Revlimid in this study to boost the GCAX vaccine or to expand the immune function of it? How do you use the checkpoint inhibitors or the PD-1, PD-L1, with the vaccine? How does that work together?
Dr. Ali: That's really very interesting. The pancreatic cancer GVAX, brilliant idea, great construct, didn't turn out to be what it was expected to be. To the pancreatic cancer group over here, I only half-jokingly, actually semi-seriously said to them, why don't you guys consider giving them Revlimid? Everyone looked at me like I was bonkers, but what I was trying to suggest was that perhaps what Revlimid does is it helps potentiate the immune system to make vaccine go down a bit better. So, they didn't do Revlimid, but they have a trial in the works, which combines pancreatic GVAX with checkpoint inhibitors.
The principle is roughly the same, which is that if what you're doing is taking your brakes off the immune system entirely, then really, its ability to wake up, release cytokines, recruit other immune cells and antigen-presenting cells which might recognize the cancer, and cancer antigens becomes a lot more robust. Now, with myeloma, unfortunately, what we saw was that checkpoint inhibitors plus IMiDs did lead to some really excellent responses, but the poor outcomes outweighed the better outcomes, so that was all put aside.
For us in the myeloma community, going forward, since we're still somewhat shell-shocked by that experience, we think about, look, why did that happen, and how can we make it better? Maybe the answer to that question is, you need to have a better, a different, rather, not necessarily better, but a different combination partner with the checkpoint inhibitor, other than an IMiD like Revlimid or Pomalidomide. There are drugs that have been altered, post. I think, potentially going forward for this trial as well, but that's at a later point in time, that maybe a straight checkpoint inhibitor combination with the vaccine might be something that we could explore, based on the immune profile that we see with the larger samples that we will have in this current study.
The dendritic cell vaccine that I mentioned earlier that has been studied by the Harvard group, they have a process already going with checkpoint inhibitors. There is a vaccine trial in the works, as well, that uses a histone deacetylase inhibitors or hypomethylating agents like -- it's one of the stats. I’m blanking on the name. The thought process there is that you use an entirely different modulating agent to see if you can make the immune system still sensitive to the vaccine, without necessarily giving you the same side effects.
We have to be a little bit careful, especially with checkpoint inhibitors. A single agent didn't really show as much effect in myeloma as other agents that cause problems. So, the answer to that question is probably, really want to be careful about your combination partner. I think that's where the vaccine might be an attractive thing because its intrinsic activity is different from giving a drug like Revlimid at the same time as a checkpoint inhibitor, and that's where this might even be more attractive, going forward.
Other settings for this kind of vaccine might actually be things that we've already discussed, which is, do I want to give this in high risk MGUS? Do I want to give this in high risk smoldering or even moderate risk smoldering myeloma? These are all things that we plan to explore in the future as this trial progresses and we get more data.
Jenny: That's amazing. I guess my last question will be, where do you want to go from here, before we open it up to questions? What do you see as the future -- you kind of touched on a little bit earlier in the show, but how do you see this being expanded in use?
Dr. Ali: Yes. Are we talking about the vaccines in general, or are we talking about myeloma therapy as a whole?
Jenny: No, the GVAX vaccine and -- well, we've talked about PD-1, and you're saying this in smoldering myeloma or MGUS. Do you see any other combinations that it might be considered in?
Dr. Ali: Yes. Checkpoint inhibitors we talked about, HDAC inhibitors, not with this particular vaccine at this time, but with other vaccines that are being explored, that is certainly an opportunity. I would like to eventually see, once the data have borne out what we've already seen, I would potentially like to see an expanded use for this. I think, for this to be used potentially as a standard, following transplant or even for patients that are not transplant-eligible, would be a very good place for this to be easily done. You come in, you get a shot, keeps a lid on things, you don't have to worry about taking heavy-duty chemotherapy, and you get yourself a much longer progression-free survival.
I also think that with novel mechanisms of reducing tumor burden, that a combination, as I mentioned, say perhaps with anti-BCMA CAR T-cells, as well as other constructs that may attack the myeloma-specific antigens, whether that’s DARZALEX or other immunotherapies; combining these with that may very well be reasonable. There are a whole host of immune therapies that now activate T-cells, and that's where I think a vaccine might find itself useful, when you're saying that I'm going to be using the combination to reduce tumor burden beyond just actually using it to keep a lid on things.
Jenny: Well, I think it's a truly amazing approach and one that would be easy to tolerate for patients, and not ongoing and forever, but still maintaining that response. I'm super excited about what you're working on and hope that this trial runs quickly so we can learn more. Sometimes it's really difficult now because the first trial, you waited seven, eight years to get results from some of these trials. It's a nice problem to have, but kind of challenging, so you can figure out like, in what combination are these best for, when you're getting these really long responses. That's kind of tough for you.
Dr. Ali: Absolutely, but that's where some of the rationale for the trial design comes into play. We thought about, say, taking patients who had single digit, MRDs, but we figured that the responses there are going to go an extra-long period of time. We wanted to find, again, this Goldilocks population where we thought we could make the biggest difference to our patients and learn the most about how that might work. That seemed to be around 10-4 in terms of MRD.
We do run into the potential issue that a patient may come into a clinic and screen for the trial, but we find, fortunately or unfortunately, depending on how you want to look at it, but fortunately, I think, maybe MRD-negative. You're like, you know what, that's a fabulous place to be. Go home, get yourself dinner and a Netflix movie. That will be great. These are all possibilities that we want to explore.
I, occasionally, use the expression that where I want myeloma therapy, whether it's drugs or CAR T-cells and this vaccine therapy to be -- prior to coming to Johns Hopkins, when I was at the National Cancer Institute (NCI); I, along with my mentor, we did the first in-humans CAR T-cell trial for myeloma. Whether it's CAR T-cells or vaccines, what I'd like to see one day is for a myeloma patient to walk into their doctor's office and say, “Hey, Doc, you know what? I've got a headache and some myeloma,” and the doctor’s, like, “Here's two aspirin and some T-cells, or here's two aspirin and a vaccine shot.” They do both. That sounds science fiction-y, but I think we’ll get there one day.
Jenny: I think it's totally amazing and it’s so exciting what you're doing. Thank you so much for sharing what you're doing today. I want to open it up to caller questions. If you have a question for Dr. Ali, you can call 347-637-2631 and press 1 on your keypad. We'll start with the first caller. Go ahead with your question.
Caller: Hi, Dr. Ali. That was fun to listen to, very densely packed with information.
Dr. Ali: Thank you so much.
Caller: I'm looking forward to reading the transcripts and unpacking that. There's a couple things -- by the way, I agree with you. I do believe that the headache was a mystery until there was aspirin and then it was off. So, we’ll look back on this someday and say, “Oh, it was -- it's always simple looking backwards; very complex, looking forward. One of the things you said in your densely packed information that you gave us was, something just popped out at me. You talked about how the GVAX vaccine could work in combination with a CAR T-cell because they're both triggering an immune response and they might play off each other. Could you expound on that?
Dr. Ali: Yes. Thank you very much for the question and for the gracious comments. I hear you on the dense packing. I will endeavor to unpack it for for these talks, definitely.
Caller: No, -- I mean, that was fun. It's mind-bending because every couple of minutes, you jumped into a new important concept. You just brought years of thought and research, then you went onto the next one and on to the next one. They're all triggering exciting thoughts, but this is one that just really stood out.
Dr. Ali: Absolutely. Thank you. There's always been this concept of, you guys may have all heard, whether it's with COVID or with CAR T-cells, that people can get cytokine release. We know that one, one immune cell wakes up and releases cytokine, it wakes up other immune cells. There's this concept in T-cell therapies in general, whether you're using bispecific antibodies or bispecific T-cell engagers or CAR T-cells, that once the system is activated, then you get epitope spreading. Although you started out targeting just BCMA, for instance, now that you've woken up your T-cells, they begin to recognize a whole host of other targets. Hopefully, as the cancer cells start dying, then more of these targets become apparent, and then the T-cells recognize even more targets.
When you give these constructs potentially at the same time, what I think is perhaps, could happen is that you could say, look, I'm going to get my BCMA therapy. That will take care of the bulk of your tumor. It will perhaps cause a little bit of fevers and cytokine release, and there will be bits and pieces of dead T-cells flying around. Those dead T-cells will release a bunch of antigens that will synergize with your vaccine construct which, as we said, has an immune adjuvant in there. Together, they will play off each other and recruit even more cells and give us a bunch of T-cells that now are exposed to a bunch of different antigens that are all cancer antigens and that may have long live memory and may stick around, like we saw with the vaccine trial, earlier on. These are concepts that are described both within the CAR T-cell world and also within the vaccine world, with our own trial and with our first trial at the NCI and with other CAR T-cell trials in lymphomas and leukemias, looking at CD19, that there is a certain thing to be said for persistence in certain settings. Some of those data are a bit controversial, but we do find that there are aspects of a cancer-specific immune response, beyond just the target that you were initially targeting that you may get to persist for long periods of time.
Another way to think about this actually is a trial that our group here that, again, Dr. Borrello has pioneered, using what are called marrow-infiltrating lymphocytes. He takes lymphocytes from inside the bone marrow with the assumption that, you know what, these are the guys that were at least around the cancer, and we're trying to kill the cancer, which is myeloma. We take these out, we culture them, and then we give them back after transplant. This study has been completed, and it's undergoing analysis, with the assumption that, look, we have these T-cells that were exposed to the cancer and recognized a wide repertoire of antigens from the cancer. If we give them back after transplant, with certain other molecules, like phosphodiesterase inhibitors, and take the brakes off the immune system, then the whole thing will -- this thing will feed off the next.
So, it turns out there's more than one way to try and skin this cat, and we want to try and find the ways to get the immune system to work using different methods that may benefit our patients. I hope that was useful.
Caller: Fabulous answer. Thank you.
Caller: Thank you so much.
Jenny: Great. Thank you so much. Okay, we have other callers. I know we're over time, but I'm wondering if you could stay --
Dr. Ali: Sure.
Jenny: -- just a few more minutes. If you could keep your question short because we have several questions. Go ahead with your question.
Jenny: Caller go ahead. What's your question?
Caller: Hi, Dr. Ali. This is Bonnie. How are you?
Dr. Ali: I'm good. How are you doing, Bonnie?
Caller: I'm good. Thanks for this great talk. I'm so happy more people are learning about your trial. My husband's in this trial, so you stimulated me to ask some questions. When you do repeat bone marrow biopsies, at what time and point would you expect to see a response and how much -- is there a certain amount of copy number change that qualifies as a response?
Dr. Ali: I'm sorry, is there a certain amount of what change? Copy number change, you said?
Caller: A change in the, yes, a change in the number of copy numbers that is statistically significant to qualify for seeing a response from the vaccine?
Dr. Ali: That's a great question. The first thing is that the MRD testing on the prior trial were done after the fact. Because back when the trial started and patients started enrolling, the kind of MRD testing that is being done now simply wasn't around, so these were done after the fact, on samples that were available. That's number one. How and when the MRD may have turned or not turned for that matter, is not easy for me to identify. What I can tell you is that the median time to people going into a complete -- and everybody on the trial, on the original trial was in a near complete remission -- the median time for going into a complete remission was about 11 and a half months.
What we also know about these immune responses are that these responses take time to build. There's an initial priming event, and then there's subsequent exposures. Each of these build on each other, over time. I really hope to begin seeing at the sixth month bone marrow biopsy, the beginnings of changes in the T-cell repertoire in patients. What's interesting about your question is that when you say, “When do I necessarily expect to see changes in the MRD,” I can't answer that question just yet. More importantly, part of the knockoff effect of this trial is I don't know yet how important it might be for me to see MRD actually change. Because I know there were people on the original trial, who had M protein flying around, who are still in remission well beyond when they should have relapsed.
The thing for us to also explore is, does it matter whether we push people into deeper MRD or not, if the immune equilibrium that we're establishing keeps a lid on it? There are well-published curves looking at what do you expect to see when somebody is MRD-positive at 10-4? These are taken from different studies, so it's not as easy to compare them all of the time because the induction was different or somebody got a transplant, and so on and so forth. The principle is still there; less MRD and PFS is longer, more MRD and PFS is shorter. These are published data, and so we will be looking at if our patient had X amount of MRD, which everyone will because we want them to have more than 100 copies, how long before I saw any change in one direction or the other? That will help inform our understanding of the vaccine and where we go next.
I hope that addresses the question. I guess what I'm saying is that, do I want to see -- does it matter that I see deeper MRD, at least right now, with this vaccine? I don't know the answer to that question. That's something I'm trying to explore.
Caller: Can I just tag onto that, one corresponding thing? Since that we know sample bias exists and we know that that would definitely affect the MRD readout, does that also affect what you're looking for in seeing changes in the T-cell repertoire? Or would you see that, no matter where you sampled from?
Dr. Ali: That's a good question. If I I understand correctly, you're saying that when I'm looking at -- because there's sample bias in the way bone marrow biopsies are done, that you could hit one spot and get nothing, hit the next spot and get a bunch of cells. Is that what the question was?
Dr. Ali: That's an interesting question. By and large, when you get a good marrow sample with a bunch of cells in there with a bunch of spicules in there, then is it possible that going into an empty space gives you an empty result in the lab? Sure. I don't know if you're well aware, you guys had a second biopsy, right?
Dr. Ali: The first biopsy was suboptimal. The first biopsy was suboptimal to the point that when we looked at it, the aspirate was really aspiculate. The pathologist looked at it and said, yeah, this is full of blood. That's a waste of everyone's time. That's not something that makes any sense. The second biopsy, you know what, we took the research sample, we got an excellent core, we got the the MRD testing that we were looking for, and we got the results that we expected to see. So, it's possible that it makes a difference. It's kind of difficult to predict because bone marrows are patchy. So long as you get a good sample, I think we're okay.
Caller: I guess what I’m asking is, is the T-cell repertoire also -- does that have sample bias? Or is the response in T-cells, would that be reflective, homogeneously, no matter where you sampled from?
Dr. Ali: I would say that the -- to borrow from the solid organ setting, in the solid organ setting at the NIH, what they started doing was taking tumor-infiltrating lymphocytes, stick a needle into a tumor, they got T-cells from there, not just go straight to the blood for it. Because that's what the tumor microenvironment is, the tumor microenvironment for the myeloma is the bone marrow. As long as your sample is good, I would expect that perhaps -- I may expect more T-cells in the vicinity of a cluster of myeloma cells, but I think you will find that there are diffused changes in the bone marrow as well. If the sample is good, that should show up.
Caller: Okay, great. Thank you so much.
Jenny: Thanks, Bonnie. Thanks, Dr. Ali. Go ahead with your question.
Caller: Yes. Thank you, Doctor, very much. Two points to clarify, please. One is, how long do we have to have been on Revlimid before we start, or can we just start Revlimid once the trial starts? Secondly, do you require any kind of a maintenance from a regular myeloma drug after the treatment, or do we have to take Revlimid after the treatment?
Jenny: That’s a good question.
Dr. Ali: Yes, these are excellent. Actually, these are excellent bread-and-butter questions for the trial, and maybe I should have addressed them. Number one, everyone who's going to get on the trial has to have had a standard amount of consensus chemotherapy, so, standard induction for six cycles, followed by transplant; or if no transplant then a standard induction with six cycles. That standard induction regimen should have contained Revlimid. Ideally, people coming on the trial will have been on Revlimid and have had the response that they've had for at least the past three months.
Once people are enrolled on the trial and start getting vaccine, then they are expected to continue the Revlimid through the life of the trial. Typically, as you know, Revlimid is given with variations for 21 days on and a week off. What we try and do is, when people are getting the vaccine injections, we try and make that coincide with the middle of the cycle, so that they've been on Revlimid for at least some time and not give the vaccine when they're actually in their off-week. Bottom line with this is, have to have had at least six cycle of initial chemotherapy, it should ideally contained a Revlimid-containing regimen. You should have had the response that you're in now for at least the last three months, and have been on Revlimid for at least three prior months. Or most people who are, after transplant now will already have been on Revlimid for at least a period of time. Since we're not taking anyone who is not a year out from transplant, everybody comes to us on Revlimid in one way or another. You have to be willing and able to continue Revlimid once you start on the study. Does that answer your question?
Caller: So, even after the trial, the medicines that you give, afterwards, you expect to be on Revlimid. There are many of us who have taken Revlimid and then go off Revlimid. I've been off Revlimid now for like five years.
Dr. Ali: Yes. That's a great question. I'm sorry, I didn't mean to interrupt you. Did you have…
Caller: Yes. In that example, a patient who took Revlimid in the beginning then went off for four or five years, and now wants to go into this trial.
Dr. Ali: So, the protocol specifically provide for this instance. You will have to have been on Revlimid for the last three months, and you will have to continue on Revlimid while you're on the trial. Because the likelihood of getting the vaccine to work any better… we think that the vaccine is disadvantaged when it's not given with Revlimid. If we want to maintain a persistent immuno surveillance state with the vaccine, then the combination is to do it with Revlimid. If you have been off for five years, first of all, congratulations, it sounds like you're not taking any other therapy. Is that accurate?
Dr. Ali: You're on Kyprolis as a single agent.
Dr. Ali: If you were on Kyprolis, let's say, if you're on Kyprolis right now, and you're looking to get on the study, then to qualify for the study, you will have to be on Revlimid for three months and be off all other therapy, including steroids or Kyprolis.
Jenny: So, you’d switch.
Caller: Yes. Thank you.
Dr. Ali: Thank you.
Jenny: Great, thanks. Great question, very practical question. Okay, last question - go ahead with your question.
Caller: Yes. I'm just a little confused because I'm getting so many different variations about the 1q amp from some of the leading myeloma specialists. Is that not being high risk? It's like a 50-50 high risk. Can you comment on that? Because I’d like to be part of the study but, unfortunately, have that chromosomal anomaly.
Dr. Ali: Thank you very much for the question. There is some controversy as to the 1q amplification. There are still some older studies that shows, that suggests that it is intermediate risk, and it is median survival of seven years or more. These are interesting to me. There are a lot of nuances to this that, amongst other things, have to do with how much amplification is there? Are there four or more copies? Are we talking about a gain? Are we talking about further amplification? If you ask people like myself, who trained in Arkansas, at the Myeloma Institute, then we tend to take 1q very seriously.
The way I explain it to my patients is that, and what we learned from our experiences in Arkansas, where Dr. Barlogie and our other colleagues, Josh Epstein, Dr. Usmani, many others, designed a gene expression profile, GEP70 and GEP80. What this gene expression profile did was that it gave you a score as to whether you were low risk or high risk, based on what genes were being expressed by the samples of your myeloma. A big chunk of those genes were all on Chromosome 1. So, changes to Chromosome 1, whether it's deletion of 1p or gain of 1q or imbalances in Chromosome 1, we think, have a lot of impact on myeloma biology.
In my mind, and often the way that I explain it to my patients is that, there are a bunch of genes there that are kind of go signal genes for myeloma cells, and having amplifications of them make your myeloma be in a situation where there's a foot on the gas. It comes down how many myeloma cells have this sort of situation? I looked at a patient who has had myeloma since 2011 and is on Revlimid maintenance, was on an extended Revlimid maintenance study. When you look at the earlier bone marrow biopsies, 2% of the cells had a gain of 1q. Well, what does that really mean? It's 2% of cells. It's below the threshold.
All of these nuances come into it. How many cells are actually involved? Do they meet any sort of threshold? What do we mean? How many copies are we talking about? Is it just a gain of 1q or 1q amplification? Over and above all of that is, how has the disease behaved? If somebody comes to me and says, “Doc, I've had myeloma for five years. It was difficult to get me into remission, and I came out of remission quickly. Then I had to give salvage therapy, and then I went to a transplant, and I relapsed within six months,” all of these say something about how the myeloma is behaving and the myeloma etiology, even if I don't necessarily find it on my standard tests.
Caller: So, a small percentage would be, what, less than 5% or 4% or 2? It's a very small percentage of the total. You just said 2%, so I don’t know.
Dr. Ali: Yes, 2%, that was well below any threshold. These thresholds are typically defined by the labs that are performing these tests.
Dr. Ali: Yes. I, typically, and for the purposes of this study, always take 1q-plus seriously, especially when it hits a predefined threshold that is generally set by the labs performing these tests.
Caller: Okay. Thank you so much.
Jenny: Thank you so much for everything that you've provided for us today. We went way over time, and you've been so gracious with your time and so informative for us as patients. What you're doing is just fantastic work. We all, as patients, want to know how to just really extend the treatment that we're getting, so this is really exciting for us as patients. Thank you so much for dedicating your work to myeloma and for doing this important work.
Dr. Ali: Thank you very, very much. My hats off to all our myeloma patients out there, yourself, Jenny, all my patients, everyone else's patients, for doing what you do in facing myeloma every day. Thank you for contributing to our knowledge of myeloma and myeloma trials, in particular new drugs of myeloma. Also, thanks also to my colleagues, Dr. Borrello, and many others who have done really just excellent work in myeloma that we hope to continue building on and work towards the Big C, which is a true cure for myeloma. It's a good four-letter word to use, like love and hope.
Jenny: I love it.
Dr. Ali: Absolutely.
Jenny: I totally love it. Well, thank you so much for helping contribute to that cure, and we're excited to see what you learn from this trial. Thank you so much. I would encourage patients always, to me, this expands the reasons that you need a myeloma specialist in your corner, first of all; and secondly, the reasons you should consider clinical trials at all times, even when you're doing fairly well, because those are the patients that you're looking at, in this study. I'm a huge advocate for that and appreciate everything you're doing to run this trial.
Dr. Ali: Right. No, thank you. I agree. We are sympatico.
Jenny: Thank you so much. Thank you for all our listeners for listening to Myeloma Crowd Radio. We encourage you to tune in next week to learn more about the latest in myeloma research and what it means for you.