Point-of-Care Devices in Liquid Biopsy

Rory McCann:
Hi everyone and welcome to this podcast from Cambridge Healthtech Institute for the Next Generation Diagnostic Summit, which runs August 15th through the 18th in Washington DC. I am Rory McCann, conference production coordinator. We have with us today one of our speakers from the Enabling Point-of-Care Diagnostics Conference, Dr. Andrew Ko, professor of clinical medicine at the University of California, San Francisco.

Dr. Ko, thank you for joining us.

Andrew Ko:
It's my pleasure.

Rory McCann:
Is it feasible to use point-of-care devices in cancer detection?

Andrew Ko:
This is certainly something that we're very interested in pursuing, making something that's very user friendly that can be done within the comfort of a person's own home. It's something that could have a potentially broad spectrum of applications including in healthcare arena. A lot still needs to be worked out in this realm in terms of the specific applications, and how patients would use this technology, and how those results would then be shared and discussed with their healthcare providers.

Obviously there is a lot of excitement in going down this path and it may be ultimately a very cost effective approach, and certainly very patient and user friendly, and potentially much more cost effective.

Rory McCann:
You mention some challenges that you expect to face as you develop this technology. What are some of those challenges that you anticipate?

Andrew Ko:
I'm thinking almost in terms of being a product of successes in terms of, I can envision in my arena which is oncology, patients will have the ability to track and monitor some aspects of their disease at home. While on the surface it sounds wonderful, I think doing it without the ongoing guidance and interacting with their healthcare providers to put it in some context just could lead to potentially panic, or uncertainty, or things.

Again it's almost as I said, a byproduct of having something that might be so potentially successful and user friendly at home, I think it's still important to recognize that the results of these technologies really need to be discussed with a healthcare professional to understand them fully and understand the implications of them.

Rory McCann:
With Two Pore Guys, how are you using point-of-care devices?

Andrew Ko:
Two Pore Guys is really a company with a fascinating technology that offers a promise of this sort of point-of-care use for home use and for consumers or patients in the future. Right now we're at the point of just proof of principal with looking at this for select patients in clinics who have a cancer diagnosis.

We've collaborated on a pilot research project where some of my patients who I'm taking care of who have a known cancer diagnosis, and in their case we know that their tumor harbors a particular genetic mutation. It's something called KRAS G12D, a very specific point mutation that's seen in almost all pancreatic cancers, and a significant proportion of colon cancers, and actually a number of other different types of cancers. It's a very common oncogene that is mutated.

What we're trying to do is identify this particular point mutation in patients’ blood and urine. Right now we're still at the point of where these patients who agree to participate are giving a blood and urine sample when they see me in clinic. They're being analyzed using Two Pore Guys technology.

We're not yet at the point of saying, "Go home, test it at home yourself." That's still to come in the future, but that's ultimately where this will lead. Right now it's just showing the accuracy and ability to detect this particular point mutation in patients’ body fluid that will get us to the point where we can use similar technology more broadly within a patient's own home.

Rory McCann:
How do you think the technology will eventually impact the future of liquid biopsy?

Andrew Ko:
Right now the process by which we do liquid biopsies, which is already sort of revolutionizing the way we monitor patients with cancer diagnosis, is really getting a blood sample when a patient comes into the clinic, sending it out, waiting for turnaround time, a week or two weeks or however long, getting those results, and the associated costs, some of which is out of pocket for patients. This really may offer a much more cost-effective, inexpensive, and rapid turnaround kind of process in which to glean some of that very same information.

You can envision in the future that's for patients who are actively on treatment, monitoring their levels of particular mutations of interest in their blood and/or urine that they can even do at their own home and get a readout right away. That gets back to the point of we might have eager or anxious patients who are doing it very frequently at home, perhaps more than indicated. What do we do with that information?

On the positive side, it really is something that we can get a quick turnaround time, a rapid answer and then it might then inform treatment decisions. We might have a patient who is rendered free of cancer following an operation but their at risk for relapse. This would be a tool that they could use at home potentially to monitor for cancer recurrence by looking for these particular genetic mutations in blood at specific points it time.

Rory McCann:
Between now and then, what are some challenges you anticipate in manufacturing these devices?

Andrew Ko:
I won't try to speak for the company, but I think really the issue is having this technology and being able to do it in a very cost-efficient fashion, which I believe they're able to do. It really is these test strips, they like to use an analogy of not that dissimilar to a home glucometer where patients with diabetes are checking their blood sugars at home.

They have a test strip and on the test strip there are these pretty awesome nanopores. Basically you're just putting a small amount of blood, or urine, or saliva onto this test strip that then runs through the test strip and basically will allow for detection of single molecules whether it be DNA, or proteins of interest, or any sort of analyte really.

It basically sends off an impedance signal that with a home reader will produce a particular signature that will allow you to say, "Okay, this person has a detectable amount of this particular genetic mutation, or this protein, or this antibody, or whatever analyte it is." Then really the readout for the patient is going to be, "Yes, it's detected", sort of a yes/no, or maybe quantitation of the amounts.

Again, that information could be shared, or transmitted, or shared with the patient's healthcare provider. That can then be used to make treatment decisions. Anyway, all of that technology, the idea is to do that in a way that maybe lead to cost savings compared to current technologies requiring a send out and with equipment that would cost a lot more.

I think the other piece to this is some of these analytes that we might be looking for may be present at very low levels. I think one of the challenges for Two Pore Guys or anyone doing this sort of detection of, in this case cell-free DNA in blood or body fluid, is being able to detect at very low levels, so just having really good sensitivity. I think that's one of the ongoing challenges that we're facing.

Rory McCann:
Sounds like this technology has a lot of potential to really make a difference in a lot of patients. Do you anticipate there being any concerns on the side of the patients? How is the technology being developed in a way that they can use it on their own?

Andrew Ko:
Like I was saying, I always think information is never a bad thing to have as long as it's accurate obviously. Again, I wouldn't want patients to have this information and just have it in a vacuum and not know what to do with it.

That's why I'm saying this potentially very convenient and rapid turnaround and all those things, and again the success of this as I envision will really require patients not go rogue and sort of do this on their own without ongoing counseling and interaction with their healthcare provider to really understand part of the implications of a particular test result.

Is it something that warrants a change of treatments, or that warrants getting another CT scan, or anything like that? In some ways I think it empowers patients more but it's important that they are able to put it in context through discussions with their physician or healthcare provider.

Rory McCann:
Great. Dr Ko, thank you so much for talking about this technology with me. I'm really excited that you are going to be speaking more about it at the Next Generation Diagnostics Summit.

Andrew Ko:
Sure, it's my pleasure. I think the only other thing I'll mention is while I'm looking at this as an oncologist, really from a cancer angle, I think the possible applications of this handheld sensor, this home device or whatnot, has applicability to testing for infectious diseases, influenza, HIV, any types of things. It has potentially a wide range of applications in the medical field, in food or environmental safety, agriculture.

With further validation and with any different analytes that can be tested with this, I think it's wide open in terms of a number of different fields that this could potentially impact. Obviously we still need to do a lot more work in these respected areas but it's exciting to think about.

Rory McCann:
It definitely is. Thank you so much and hopefully we can learn more about this at the meeting in August. I'm looking forward to hearing your talk then and hearing what questions and discussions it brings up.

Andrew Ko:
Absolutely, I look forward to it.

Rory McCann:
That was Dr. Andrew Ko, a professor of clinical medicine at the University of California, San Francisco. He'll be speaking at the Enabling Point-of-care Diagnostics Conference, part of the upcoming Next Generation Diagnostics Summit, which runs August 15th through the 18th in Washington DC.

I'm Rory McCann, thank you for listening.