Prior to this year’s virtual annual meeting of the American Society of Clinical Oncology (ASCO), we spoke with Blythe Adamson, PhD, MPH, principal quantitative scientist at Flatiron Health. Here she discusses study results she was presenting on the use of immune checkpoint inhibitors in end-of-life care.
Please tell us about the abstract you are presenting at ASCO on adoption of immune checkpoint inhibitors and patterns of care at the end of life.
This study was really led by a tremendous investigator, Dr Fauzia Riaz, who at the time was at Yale University at the COPPER Center and has now recently moved to Stanford. When she designed this study, you know, she was really interested in this end-of-life quality measure that's often used, which is that patients who are at the very end of their lives, it's not really considered a good practice to administer really aggressive therapy at the end of someone's life. Because it's likely to just add a lot of distress to these patients and add unnecessary costs when it's the least likely that they're going to achieve meaningful health gains from these things.
And so, you know, while we've had a lot of incredible scientific breakthroughs with immune checkpoint inhibitors in recent years, across multiple tumor types, in this real-world evidence study, we're looking at the unintended consequences, maybe of the therapeutic profile that we're seeing for checkpoint inhibitors, which is that they have a pretty favorable tolerability and very high expectations of effectiveness.
And so Dr Riaz had a hypothesis that she wanted to test, which was that after these new products were approved by FDA, she expected that it would increase the percentage of people who are receiving systemic therapy right at the end of their life which would, by this general quality measure, be not a good thing. So, what we did was defined a cohort of patients who died between 2013 and 2017 and looked at 2 different cases of 2 different types of cancer, where we saw an FDA approval of one of these types of drugs. So this was advanced or metastatic non–small cell lung cancer and metastatic melanoma, and both of those received FDA approvals during this time.
But then we also needed to select a negative control. So, we wanted to make sure that we could attribute, really, changes in the end-of-life care, to approvals of these drugs and make sure that it wasn't just something else that was going on in the world at the same time. And so, for that negative control, we chose colorectal cancer because during this time period, there were no medications of this type that were approved by FDA in that time period, and so we wouldn't expect a similar increase if there was one.
And so, we assembled together a pretty large cohort with more than 20,000 cancer patients and showed that the FDA approvals were indeed associated with an increase in the percentage of patients who received systemic therapy at the very end of their life. And the biggest driver of that was really the use of these checkpoint inhibitors. So, that was how we walked through the study from hypothesis all the way to testing it and learning from those experiences.