Companion Diagnostics Q&A: Dan Snyder, Molecular MD

October 10, 2017

What are the particular challenges around creating a companion diagnostics for PDL-1 and other immunotherapies?

I think when you are looking at diagnostics associated with the immune system versus diagnostics tied to an oncogene, with an oncogene things are much more black and white. There tends to be a lot more gray area in I/O and it tends to be more iterative.

The other piece of this, though, is that drug companies like that grey area in some ways because they want to use these IO therapies in terms of combinations and they want to continue to have the freedom to test these combinatoins without being restricted by some of these biomarkers. With targeted therapies, you get response or not response. With IO you may not be able to get optimal response, but you can get partial response.

Are we moving to an age where it is almost necessary to analyze multiple analytes in a single test?

Yes. And I think that gets more challenging in terms of how physicians are going to use that data. how you combine the data and the expense that goes into that. When you are looking at more targeted data versus IO data and combining that, I think it is going to be heavily dependent upon how far pharma really wants to push this in terms of the diagnostics piece and what their clinical trials effectively demonstrate.

In some cases, they just want enough data to get the indication. Whereas if you have a really strong biomarker you are going to get that much more efficacy. For most, they just want to get the indication and go from there. Looking at these combination therapies and how the role of diagnostics is going to play out, given the complexity, is yet to be seen. Because for physicians, even now, it is hard for them to keep up with all the diagnostic information they are getting.

IHC is a tried and true testing technology. But are we moving into an era where there will be a much broader array of technologies and many newer technologies that will be used in diagnostics. If so, does that present problems in terms of the installed base?

It is at least a hindrance. Ideally, when a drug company is using a diagnostic to support their approval indication, particularly if there is a potential drug class where there are multiple players competing, they all want to compete on the same level in terms of the same diagnostics that is performing at the same sensitivity.

Everyone knows IHC and even though ther is some subjectivity based on your pathologist it is a fairly standard approach. On some of these other modalities at least in terms of supporting the development, for us, the real opportunity will be to how do we standardize these tests in how they are used and how they are interpreted.

Let’s talk about some of the emerging biomarkers in I/O like tumor mutational burden and MSI. What are the opportunities here for developing companion or complementary diagnostics?

I think one of the greatest challenges is going to be standardization of these tests from an interpretation perspective, and cutoffs perspective. These are pretty complex tests.

But even prior to approaching standardization, as a company who partners with pharma on these tests, we are do not yet have a lot fop pharma companies knocking down our doors saying we need to be enrolling patients using this data.

I think they are certainly collecting samples internally and they are running the tests, but they want to develop their own proprietary data to best use these tests.

For us the biggest challenge is how to best validate them for their purpose and indication for use. We have all the platforms and basic technologies to perform these but right now we are just collecting information on how best to validate these tests so they will be able to be deployed in clinical trials.