The first commercial PD1/PD-L1 interaction and phosphorylated PD1 in situ assays are now launched.
PD1/PD-L1 signaling has proven to be significant in cancer progression, and immune checkpoint inhibitors targeting PD1/PD-L1 have emerged as essential therapies for cancer patients.1 But despite the success, many patients do not benefit from these therapies, and predictive biomarkers improving patient stratification are needed.1-3 Today, the leading technology used to determine whether a patient is likely to benefit from PD1/PD-L1 immunotherapy is PD-L1 immunohistochemistry (IHC). However, existing PD-L1 assays are insufficiently standardized, and PD-L1 positivity of patient samples doesn’t directly correlate with activation of the inhibitory pathway or patient response to immune-check inhibitors.3 PD1/PD-L1 interaction has predictive value for patient prognosis and survival. Still, up until now, the possibilities to detect it in tissue samples have been very limited3.
PD1 activation is an essential step in the signaling pathway and requires PD1 to be both bound to PD-L1 as well as phosphorylated 4, 5, yet phosphorylation of PD1 in situ is not well studied, mainly due to a lack of specific methods.
Here is how our newly developed in situ assays make a difference. Navinci has developed two Proximity Ligation Assays for the specific detection of the PD1/PD-L1 interaction and phosphorylated PD1.