NEW YORK – Qiagen announced on Monday that it has received US Food and Drug Administration approval for a real-time PCR companion diagnostic to identify patients with certain gastrointestinal tumors who may be eligible for treatment with Blueprint Medicines' Ayvakit (avapritinib). Qiagen and Blueprint Medicines collaborated to develop the assay.
The Qiagen Therascreen PDGFRA RGQ PCR kit is the first FDA-approved companion diagnostic to detect a mutation in the platelet-derived growth factor receptor alpha (PDGFRA) gene that is associated with primary resistance to other drugs in patients with unresectable or metastatic gastrointestinal stromal tumors (GIST), Qiagen said in a statement.
The test uses genomic DNA from formalin-fixed paraffin-embedded tumor tissue processed on the QIAamp DSP DNA FFPE Tissue Kit for sample preparation and the Rotor-Gene Q instrument for DNA amplification and mutation detection.
Ayvakit is a tyrosine kinase inhibitor designed to target the PDGFRA exon 18 D842V mutation. It was approved in 2020 by the FDA for the treatment of unresectable or metastatic GIST harboring a PDGFRA exon 18 mutation, including PDGFRA D842V somatic mutations.
GIST patients harboring the D842V mutation in PDGFRA exon 18 show primary resistance to previously approved TKIs, Qiagen said, and approximately 6 percent of patients with newly diagnosed GIST have PDGFRA exon 18 mutations, the most common of which is the D842V mutation.
Qiagen said the approval of the PDGFRA RGQ PCR kit brings the total number of its FDA-approved companion diagnostics to 12.