The therascreen PIK3CA RGQ PCR Kit is a real-time qualitative in vitro diagnostic PCR test for the detection of 11 mutations in the phosphatidylinositol 3-kinase catalytic subunit alpha (PIK3CA) gene using a sample of DNA extracted from either formalin-fixed, paraffin-embedded (FFPE) breast tumor tissue or K2EDTA anticoagulated blood plasma, taken from a patient with breast cancer.

The therascreen PIK3CA RGQ PCR Kit is the first companion diagnostic (CDx) test approved by the FDA to aid in the selection of patients with breast cancer who may be eligible for treatment with the alpha-selective PI3K-inhibitor, PIQRAY (alpelisib), in combination with the estrogen receptor antagonist, fulvestrant.