This year is turning out to be a banner year for the multiplexed assays-first came the news of FDA approval to OVA1TM (a multiplexed serum protein test) for the detection of ovarian cancer (see my previous post). Now comes the news that ArrayIt Diagnostics has licensed out ovarian cancer biomarkers from Wayne State and will apply for pre-market approval with FDA for its diagnostic test.
OVA1TM is a qualitative serum test that combines the result of immunoassays against five different proteins into a single numerical score using a proprietary algorithm to indicate likelihood of ovarian cancer. The five proteins tested are Transythretin (TT), Apolipoprotein A-1 (Apo A-1), β2-microglobulin (β2M), and Transferrin (Tfr) on Seimens BN™ II System and CA 125 on the Roche Elecsys® 2010 system. Though the test uses multiple immunoassay tests for predicting ovarian cancer but technically it is essentially five separate monoplex immunoassays stiched together by an algorithm.
The ArrayIt system on the other hand is a true multiplexed assay based on the protein array technology developed by Prof Tainsky at Wayne State University. Prof Tainsky’s technology measures autoantibodies against the multiple tumor antigen simultaneously in a single sample. Using antigen array with 65 different tumor antigens immobilized on a single chip a sensitivity of 55% and specificity of 98% was achieved.
The final format that ArrayIt will use is not clear and can be protein array format or bead array platform like Luminex. Whatever is the platform, it is clear that multiplexed assays are finding their niche in diagnostics and possible drug discovery.