The prostate-specific antigen (PSA) is a naturally occurring enzyme. In patients suffering from prostate cancer, it is produced in excess, which is why PSA detection is used for non-invasive early screening for carcinomas. That's the good news, but the bad news is that in three out of four cases, the overproduction of PSA is not linked to a tumor, but to an infection, which the doctor discovers only after a biopsy. Tissue biopsies are very uncomfortable for patients and stress health insurance funds. In the US alone, PSA-related false alarms cost $2 billion annually.

 

Young ETH biochemist Ralph Schiess thought there must be a solution and searched for alternatives to the PSA test in his doctoral thesis at the Institute of Molecular Systems Biology. He went on the assumption that 70 percent of prostate cancers result from genetic defects. Such mutations depend on a protein chaos, and Schiess was able to detect four proteins that are unmistakably associated with the relevant defects.

 

The breakthrough came with a small study at the Kantonsspital St. Gallen. It turned out that, like the PSA test, the new test doesn’t overlook any tumors, but incorrectly indicates only one out of five cases. Schiess together with economist Christian Brühlmann founded Proteomedix AG in spring 2010. The clinical trials will start in 2013 and, if successful, the new diagnostic tool will reach the market in two to three years.

 

Also of interest to investors is the fact that the biomarker technology from Proteomedix can be used not just in the diagnosis but also in the treatment of prostate cancer. The reason is that cancer drugs work very selectively: what works with one patient can have no effect on another. “An analysis of the specific protein mixes in the blood,” says Schiess, “can provide valuable clues in choosing the right drug.”