The progression-free survival (PFS) of patients with heavily pre-treated rare or refractory cancer usually declines with every new line of therapy. However, new research presented at the European Society for Medical Oncology (ESMO) 2017 Congress has shown a one month increase in PFS in these patients when treated with Caris Molecular Intelligence–guided treatment compared to prior therapy. This clinical benefit was mainly driven by the precise and evidence guided use of available chemotherapies and only very few patients were given expensive targeted therapies.
Researchers pooled data from four prospective studies. In total, 140 patients from Australia, Austria, the United States and Lebanon were included in the study. These patients, who had a range of solid cancers including breast cancer, colorectal cancer, non-small cell lung cancer, gastric cancer, and pancreatic cancer, were profiled by Caris Molecular Intelligence between March 2010 and August 2016. Caris Molecular Intelligence testing included a combination of sequencing (Sanger, Next-Generation Sequencing 592 genes including total mutational load (TML) and microsatellite instability (MSI), pyrosequencing) protein expression (immunohistochemistry including PD-L1), gene amplification (CISH/FISH) and RNA fragment analysis.
It is well established that PFS is expected to decline over subsequent lines of therapy for patients who have refractory cancers. The researchers were looking at the effect on PFS when patients were treated with Caris Molecular Intelligence-guided treatments.
Figure 1: Kaplan-Meier showing PFS comparison in prior and MMP-guided treatment lines in 140 patients treated according to the MMP report.
In the prior line of treatment which patients received, the median PFS was 89.5 days. However, when treated in-line with the results of Caris Molecular Intelligence, the median PFS was increased by over 30 days to 120 days. In addition, 8% of patients remained progression-free for one year of PFS follow-up. Seventy-three patients (52%) had a PFS ratio ≥ 1.3.
Importantly, most treatments that patients received when guided by CMI were conventional chemotherapy treatments alone (71%). This is significant as most of these treatment decisions were driven by the results of IHC testing. By comparison, 9% of patients received targeted therapy alone, 8% received targeted therapy and chemotherapy together, 4% received hormone therapy and targeted therapy together, 4% received hormone therapy alone, 2% received both hormone therapy and chemotherapy, and 2% received immunotherapy alone. The fact that the majority of treatments guided by CMI were traditional chemotherapies means that there is not a significant cost increase by treating in-line with the Caris Molecular Intelligence report when compared with the costs of the prior line of treatment.
Figure 2: Breakdown of CMI-guided treatments in 140 patients.
This research highlights the clinical benefit and utility of Caris Molecular Intelligence to improve progression free survival for patients who have refractory or rare cancer and have previously been treated. It is soon to be published in The Journal of Cancer.
- Seeber A et al. Comparison of progression-free survival (PFS) on comprehensive multiplatform profiling-guided therapy to PFS on prior therapy: A pooled analysis from 4 contemporary prospective studies. 2017. Presented at ESMO 2017. [PDF]