As you know, right now we have early detection or screening tests for only four cancers that have been proven and are in routine use. So 70% of cancer deaths and 70% of incidental cancer diagnoses are due to cancers for which we have no early detection capabilities. As a practising oncologist I get questions all the time from family, friends, from my patients on behalf of their family and friends – what can I do, I have a family history of kidney cancer, pancreatic cancer, ovarian cancer, you name it? We don’t have a good answer for that.
Blood tests that are designed to detect many cancers at the same time, so-called MCEDs, or multi-cancer early detection tests, really promise to change that and expand cancer screening beyond the four cancers we have today to many, if not most, cancers.
What was the methodology behind this study?
At Exact Sciences we’ve been committed to a science-driven approach to blood-based multi-cancer early detection. It began with landmark studies of tests that were based on two biomarker classes – mutations and proteins – and that was published in 2020, the first prospective, large, interventional study to evaluate such a biomarker. Over the last couple of years the team has been working hard to improve on that test by adding additional classes of biomarkers.
So what we reported at ESMO today is the results in a retrospective case control study with a three biomarker panel and a four biomarker panel. What’s really the most important finding from our study is that with the four biomarker panel we were able to markedly improve sensitivity for early stage, stage 1 and stage 2 cancers, exceeding 30% sensitivity for stage 1 and approaching 40% for stage 1 and 2 cancers. Those are unprecedented numbers for blood-based multi-cancer early detection.
What were the implications of this study?
What we’re going to do next is complete an additional independent prospective case controlled study. In 2023 we plan to launch the largest ever conducted multi-cancer early detection prospective study in the United States, the SOAR trial, that’s going to be designed to gather the sort of data that we’ll need to go to the FDA and apply for an approval of an MCED test. So we’re working hard to move forward.
Is there a way to improve the sensitivity?
We continue to work at that and the primary ways in which we’ve been able to improve sensitivity is by moving to a four biomarker panel and combining four different biomarkers. We’re continuing to refine the panels and the selection of the biomarkers within each class and we’re also working on developing a shared classifier that will essentially interpret all four biomarkers together in a single artificial intelligence style analysis. So that’s where we see the way forward for potentially further improvement.
Where does this sit in relation to other screening options?
The current screening landscape is limited to four solid tumours and this approach promises to really address close to all the other cancers that currently go unscreened. So we think that in conjunction with current proven screening blood-based multi-cancer early detection is the way forward to radically expand our ability to detect cancer early.
Were there any false positives?
False positives, of course, are situations where a blood test suggests the presence of cancer but no cancer is found. The multi-cancer early detection tests, including ours, are all geared to a very high level of specificity to limit the number of false positives. That continues to be a cornerstone of our effort. But one can’t eliminate false positives, they’re common in medicine, they’re common with all kinds of tests in medicine. So the second part of that is to develop an efficient, effective and confident path to resolving those. That’s a component of our plans, is to make sure that when a signal positive develops we have a rapid, clear and confidence-inspiring approach to either confirming the diagnosis of cancer or confidently ruling it out.
From a patient’s P.O.V. why would they be interested?
That’s something I encounter a lot in my journey as an oncologist. People are very interested, as you might imagine, in doing what they can to reduce their risk of cancer. Right now, outside of the four common cancers they really have nothing to turn to. So the level of interest amongst people I’ve talked to, my friends, my patients’ families, in the ability to take advantage of a screening test for most cancers is really great because they want to find ways to protect their health.
I appreciate the opportunity to chat with you. This is an exciting and important area. The main point I’d really want to make is that our multi-biomarker class approach is something that we started with six years ago, ran the very first large-scale prospective interventional study, really launched the field of MCED and now our results are producing a compelling combination of sensitivity and specificity that give us great confidence to move forward with a large prospective study and make this a reality.