Andrew Klink: In 2016, after recently completing an RWE study to determine patient response to cancer therapy, our team was surprised by the findings. When we analyzed the physician inputs in aggregate, across a cohort of patients, we found that the proportion of patients with complete or partial response to therapy was much higher than the responses reported in the drugs’ randomized clinical trials.
We wanted to understand the reasons behind this variance, so we sought out qualitative feedback from the participating physicians, to learn what measures or tools they were using to evaluate patient response. We found that most participating physicians weren’t using standardized criteria at all; they were primarily using their own clinical judgment to evaluate patient response. For example, perceived clinical benefit demonstrated by improved lab values or less symptom burden might have contributed to a more subjective interpretation of response.
While the treatment of most forms of cancer can definitely be both an art and a science, it was inarguable that these methods for measuring patient response were far more subjective, and less consistent, than the gold standard, RECIST. The RECIST classification compares changes in a patient’s lesions and tumor sizes over time, and is the methodology typically used to measure solid tumor response to therapy in clinical trials. We hypothesized that the more objective RECIST approach would be likely to deliver more accurate patient response results than those formulated based on the individual clinical judgment of each participating physician.