Researchers said responses may depend on prior immunotherapy.
Prior immunotherapy treatments in patients with advanced melanoma can lead to influenced responses in PD-1 blockade immunotherapy.
In a recent study,1 researchers from the University of California, Los Angeles (UCLA) Jonsson Comprehensive Cancer Center aggregated data from 7 clinical cohorts of patients with advanced melanoma. These patients (n=514) had all received immune checkpoint inhibitor (ICI) therapy. Following melanoma tumor biopsies, they had all either undergone exome sequencing (WES), RNA-sequencing, or matched WES and RNA-sequencing. However, through the process of exclusion, the study later involved a total of 427 patients.
Researchers also collected demographic information from the cohorts, including age, melanoma subtype, original study cohort, point in time therapy was received, prior CLTA-4 blockade therapy status, RECIST 1.1 response to therapy, sex, and treatment regimen.
Past treatment regimens included anti-CTLA-4 monotherapy, anti-PD-1 monotherapy, or combination or sequential therapies involving both therapies. Participants had either had tumor biopsies with WES (n=284) or RNA-sequencing (n=442). Of these, 188 patients had tumor biopsies involving matched WES and RNA-sequencing.
As a result of the study and cohort data analysis, researchers made note of several findings, including:
"We undertook this project to establish a resource for other researchers, with the goal of identifying statistically significant correlates of melanoma responses to anti-PD-1 therapy,” said Katie Campbell, PhD and lead study author, in a press release.2
Campbell noted that the greatest differences became evident when researchers accounted for patients’ history of prior treatment with an anti-CTLA-4 blockade.
“The context in which a biopsy is collected needs to be considered to better define how biomarkers should be implemented in the clinical setting,” Campbell said.