Current imaging options to assess the responses of liver cancer patients to treatment suffer from blurry resolution, making it hard to develop radiotherapy plans.
Eye90 Microspheres, developed by ABK Biomedical, enable superior CT-based dosimetry , allowing for more more accurate dose estimates for treatment planning.
This work was awarded the Best Paper of the Year in the journal EJNMMI, and is being further assess in the Route90 Study.
Read the original research: https://doi.org/10.1186/s40658-022-00447-1
Image Source: Adobe Stock / FH Multimedia
00:00:03 Dr Courtney Henry
Hello and welcome to our research pod. Thanks for listening.
00:00:07 Dr Courtney Henry
My name is Doctor Courtney Henry. I’m a researcher in the field of medical physics and more specifically, nuclear medicine physics, which is a discipline that studies how small amounts of administered radioactivity can diagnose and treat disease.
00:00:20 Dr Courtney Henry
In my current work, I attempt to improve the diagnosis and treatment of cancer by advancing our understanding of nuclear medicine imaging and its role in absorbed radiation dose calculations or radiation dosimetry.
00:00:32 Dr Courtney Henry
I was first introduced to nuclear medicine research in Graduate School after I accepted a position as a research assistant and my professors lab.
00:00:40 Dr Courtney Henry
After I graduated, I continued down this path, searching for a PhD projects and discovered Doctor Alistair Sim at Dalhousie University in Halifax, NS he was studying a novel radioactive particle use for the treatment of liver cancer, and after accepting this PhD project I became more familiar with the concept of radio embolization.
00:01:00 Dr Courtney Henry
And was introduced to ABK biomedical and years later to their current CMO, doctor Aravind Arepally, who has also joined us here today.
00:01:09 Dr Courtney Henry
Aravind, could you introduce yourself and provide us with some background as well?
00:01:13 Dr Aravind Arepally
Hi, Courtney. Thanks everyone. I’m Aravind Arepally, I’m the chief medical officer for ABK Biomedical, which is developing a novel, new Y-90 microsphere technology that better leverages some of the imaging physics that Courtney has just recently mentioned. But we’ll touch on that a little bit later.
00:01:29 Dr Aravind Arepally
I joined ABK in the fall of 2022 after watching some of the clinical and technological advances they were making. Specifically, the field of interventional oncology.
00:01:37 Dr Aravind Arepally
My background, I’m an interventional radiologist with focus and expertise in the treatment of liver cancers and particularly using Y-90 radioembolization. Although this procedure has been around for about two decades, and there’s always room for continuous improvements that have the potential to help.
00:01:57 Dr Aravind Arepally
Patient outcomes and one particular area that’s really been challenging and it’s sort of an interest to me is there’s really no currently standardized way to assess the tumors after treatment with Y-90 and really see if we’ve adequately treated the tumor fully and with the proper dose.
00:02:17 Dr Aravind Arepally
So our counterpart in radiation oncology or medical oncology, they have a pretty much standardized process for assessing before and after the methodology, especially the radiation treatment planning and coverage of the tumor before and after this is something that’s lacking currently right now with the technology with Y-90.
00:02:37 Dr Aravind Arepally
I mean, we go through all this effort and the patient goes through a lot of the treatment. We should really be sure we’ve done the best we can and we’ve got the best shot at beating cancer right now, right?
00:02:47 Dr Courtney Henry
Yeah, that’s exactly right. And the only way we can validate the success of the treatment today is with post procedure, nuclear medicine imaging using positron emission tomography known as pet or single photon emission computed tomography known as SPECT post procedure is simply referring to that after we’ve done the procedure, we’re going to take some pictures either using Y-PET or SPECT to measure that absorbed dose.
00:03:11 Dr Courtney Henry
These are non invasive imaging modalities that can measure the radioactivity distribution and the corresponding absorbed radiation dose, and this is incredibly important measure because we need to know what radiation dose causes damage in healthy tissue and what dose to deliver to observe a reduction or elimination of the tumor volume and this is referred to as a dose response relationship which.
00:03:32 Dr Courtney Henry
Isn’t as well understood in Radioembolization as it is with external beam therapy, for example, where there’s a much longer observational history, and I think our lack of understanding of this dose response relationship and rationalization can be partially attributed to that suboptimal post procedure assessment you’ve mentioned, Aravind.
00:03:53 Dr Courtney Henry
Ultimately, the problem with current post procedure dosimetry options, namely PET inspect imaging, is that they both suffer from relatively poor spatial resolution, meaning the images they produce have a blurry characteristic that’s similar to images produced from an out of focus camera. You can imagine how this makes them challenging to use.
00:04:10 Dr Courtney Henry
For accurate radiation dosimetry calculations and it was actually back during my PhD at Dalhousie University that I attended to address this problem and that research was possible due to a the case production of Yttrium 90 or Y-90 microspheres for radio embolization.
00:04:25 Dr Courtney Henry
That are not just visible using PET inspect imaging, but also with CT imaging as well. These novel spheres are called Eye-90 microspheres. That’s E Y E 90, as opposed to just the letter Y as in Y-90 microspheres.
00:04:38 Dr Courtney Henry
Aravind, from your side of things, what’s your experience with post procedure, imaging and the clinical benefits of these novel Y90 microsphere?
00:04:46 Dr Aravind Arepally
Well, in my time treating patients with Y-90 Radioembolization, we currently use post procedure SPECTat my institution and that’s used to assess really qualitatively tumor coverage. However, we really don’t do an adequate job on the quantitative side.
00:05:04 Dr Aravind Arepally
For most patients, this less than precise information that comes from these diagnostic makes really the time and resources spent questionable like we’ve already talked about. And that’s why I think I’ve been very interested in how Eye90 works.
00:05:19 Dr Aravind Arepally
So first of all, I think the multi modality imaging, in other words, we can see Eye90 with PET SPECTas well as CT. It really has the opportunity to change how we measure the success of radicalization. One important ways, it’s different from conventional Y-90 is that the microspheres have a calibrated radio opacity.
00:05:39 Dr Aravind Arepally
So in other words, these microspheres are not only visible with a conventional CT scanner.
00:05:46 Dr Aravind Arepally
It takes the concentration of microspheres specifically in a target tissue.
00:05:50 Dr Aravind Arepally
And it allows you to correlate that specific concentration and its radio opacity to actually a specific dose. We can use that to actually calculate the absorbed dose to the tumor and we use that data and translate that data using some advanced physics and software to calculate how much dose.
00:06:11 Dr Aravind Arepally
Actually goes into that target tissue. With the predictable and quantifiable imaging data this provides us, this really has the ability and gives the physicians more information.
00:06:24 Dr Aravind Arepally
Regarding the bio distribution of the radiation and also to be allowed to quantify it and say what was the dose that was delivered specifically to that tumor?
00:06:36 Dr Aravind Arepally
All of this which say is we can identify areas now where there may be misses or cold spots in the tumor, which would need follow up or may need some kind of additional treatment in addition to Y 90. So it’s a big leap forward to have that kind of measurable, quantifiable, provable, actionable information.
00:06:57 Dr Aravind Arepally
I mean, just think of a patient getting to hear that doctors are even more confident that their tumors are highly likely to shrink and then not have to wait three months to see what is the response rate. We can assess immediately what the distribution looks like and what kind of dose was delivered to the tumor and then therefore we can tell immediately to the.
00:07:21 Dr Aravind Arepally
Patient, I think I’ve got the target dose to the tumor and we’ll do the follow up imaging, but I think we will be able to
00:07:28 Dr Aravind Arepally
be fine or if you didn’t get the dose into the tumor fully, you can immediately have an actionable situation where you said, look, I think we need to come back and re-treat this or we may need to do another option.
00:07:40 Dr Aravind Arepally
So this takes away that window of three months of unknown what’s happening and waiting to see the results of the therapy to now shortening that process where you have a more immediate feedback to the physician and to the patients.
00:07:55 Dr Aravind Arepally
And I feel like that will really help the whole process and also help to also figure out what is the dose we need to give to the tumor and be able to advance that process overall.
00:08:07 Dr Courtney Henry
I agree, Aravind, with these Eye-90 microspheres, we no longer have to rely on just PET or SPECT imaging alone for post procedure dosimetry.
00:08:16 Dr Courtney Henry
The composition of Eye-90 is such that it highly attenuates the incident X-rays in CT imaging and shows up pretty clearly on the reconstructed images and since CT has excellent spatial resolution relative to PET and SPECT. This provides us with the potential for very accurate dosimetry and this was the basis of my thesis, that CT imaging of these novel.
00:08:37 Dr Courtney Henry
Eye90 microspheres could potentially improve dose estimates following radioembolization. And over the course of my PhD I published my research findings that described how to perform CD based dosimetry with these microspheres.
00:08:53 Dr Courtney Henry
And my most recent paper on the topic, published in EJNMMI Physics and linked in the description of this episode.
00:08:59 Dr Courtney Henry
That’s the European Journal of Nuclear Medicine and Molecular Imaging.
00:09:03 Dr Courtney Henry
We compared PET and CT based asymmetry following the administration of Eye-90 to a rabbit model.
00:09:09 Dr Courtney Henry
And we showed that CT based dosimetry is superior and that it provides more accurate dose estimates which are more important for understanding this dose response relationship and ultimately improving patient outcome.
00:09:22 Dr Courtney Henry
This work was recently awarded the best paper of the year in the Journal, which is a huge honor and I think speaks to the value of this research for clinicians and patients undergoing the treatment. We were pretty excited and surprised, I’ll say, to hear back from them, it’s a pretty big deal in the in the research world to get the best paper of the year. So we were very, very excited to see that and the success.
00:09:42 Dr Courtney Henry
Motivated a collaboration between myself, ABK biomedical and MIM software to develop a clinical solution to implement this new CT based dosimetry framework.
00:09:52 Dr Courtney Henry
We spent some time optimizing the workflow utilizing patient data and images from a phase one first in human Eye-90 micro through study that was recently conducted in New Zealand and this set the stage for the next human study with this advanced technology and we look forward to implementing CT based on symmetry in this pivotal study. Aravind, could you go into some of the specifics for this clinical trial>
00:10:14 Dr Aravind Arepally
Sure, Courtney. So the outcomes really are coming from the research of you and Alistairs on CT dosimetry. So we’re excited to study the Eye-90 microspheres as an exploratory endpoint in our new Route 90 FDA pivotal study. It’ll really be the first time we can prospectively evaluate this technology in humans.
00:10:34 Dr Aravind Arepally
In a controlled setting with the appropriate use of CT scanners, specifically addressing CT dosimetry.
00:10:40 Dr Aravind Arepally
So we’ll also be performing the standard of care in addition of using post procedure SPECTCT dosimetry for each of these patients.
00:10:47 Dr Aravind Arepally
So now we can actually measure and compare the two models of post procedure to symmetry CT based dosimetry and SPECTCT. There’s huge clinical value.
00:11:00 Dr Aravind Arepally
And health benefits utilizing the CTC based tech Analogy. So overall it’s a very exciting time being able to really translate some of the work you’ve done in the past and now implementing this into an FDA pivotal trial called Route 90.
00:11:16 Dr Courtney Henry
Absolutely, Aravind. I’m excited to see this work getting the attention it deserves and we’ll certainly follow this clinical trial closely. For now, though, that’s all we have time for. If you’d like to know more about a BK biomedical and all the research underway there, you can just head to ABK biomedical.com. That’s the letters A B and K there they will have the links to the papers we’ve discussed, including the EJNMMI paper and the show notes for this episode, as well as links to the Route 90 trial Info.
00:11:41 Dr Courtney Henry
Thanks for listening and that’s goodbye from me.
00:11:44 Dr Aravind Arepally
And goodbye from me.