Multicenter evaluation of the Idylla IDH1-2 Mutation Assay Kit for detection of IDH mutational status in glioma

The study evaluated the concordance and failure rate of the Idylla IDH1-2 Mutation Assay Kit compared to routine reference methods in real-world clinical settings using archival formalin-fixed, paraffin-embedded (FFPE) tissue, and extracted DNA from glioma patients. This was a retrospective, observational, non-interventional study conducted across 12 centers. Each site selected archived FFPE tissue (n = 135) and extracted DNA samples (n = 75) from glioma patients; the sets were enriched with isocitrate dehydrogenase (IDH)1-2-mutation-positive samples. All samples had previously been tested for IDH1-2 mutational status using routine reference methods and were retested using the Idylla IDH1-2 Mutation Assay Kit run on the Idylla System. Discordant results were further assessed using a third method, when available. Concordance was calculated using overall percent agreement (OPA), positive percent agreement (PPA), and negative percent agreement (NPA) values, excluding invalids and error test results. Failure rate was calculated as errors plus invalid test results on total sample set. Out of the 210 samples, reference methods had identified 111 samples with an IDH1 mutation, 18 with an IDH2 mutation, and 81 as IDH1/IDH2 wildtype. The final concordance analysis resulted an OPA of 98.51%, a PPA of 97.64%, and an NPA of 100.0%. The validity of the Idylla IDH1-2 Mutation Assay was 98.06%. The Idylla IDH1-2 Mutation Assay Kit showed comparable performance to other well-validated methods for IDH mutation analysis while demonstrating excellent assay turnaround times.