A company with a commercial interest in developing diagnostic tools for neurodegenerative diseases claims, recently announced in a press release, that it will start marketing a blood test for Alzheimer disease within the year. Power3 Medical Products, based in The Woodlands, Texas, is currently in the validation phase of their product’s development. According to CEO Steven Rash, the test, called NuroPro, can also identify patients with Parkinson disease and ALS. In an interview with Alzforum, Rash said that the test is based on a panel of 59 protein markers, but he was reluctant to divulge any specifics. He said that the company has been able to identify specific disease profiles based on these markers using a company database of 800-900 patients. The test has an accuracy of 90 percent for AD and better still for PD, Rash said, but there are no publicly available data to verify this claim.
What is known is that the test is based on 2D gel electrophoresis followed by quantification of the protein markers. Rash admitted that most commentators are a little surprised at the choice of methodology. Two-dimensional gels are not as sensitive as more modern proteomics methods or immunoassays, but the company claims they can detect as little as 0.23 ng of protein. “With 2D gel we get great specificity, sensitivity and reproducibility. We have strict collection and handling protocols, and very strict SOP [standard operating procedures] within our facilities,” said Rash. The company recently received CLIA approval (the Clinical Laboratory Improvement Amendments program is run by the Center for Medicare and Medicaid Services), which is necessary for any non-research diagnostic testing performed on humans in the U.S. In 2006, researchers at the company published their basic approach, showing that proteins of the immune/complement system contributed to disease profiles for both PD and ALS (see Goldknopf et al., 2006 and Sheta et al., 2006). It is not clear if the 59-protein panel contains these same markers.
NuroPro is currently undergoing validation in the U.S. and also in Greece. The U.S. study is being conducted at Sun Health Research Institute, Sun City, Arizona, under the direction of Marwan Sabbagh and will test a total of 300 subjects, including controls, AD, and PD patients. The Greek study is lead by Katerina Markopoulou from the University of Thessaly Medical School in Larissa. According to Rash, Markopoulou contacted the company after reading their initial findings. “We’ve been very happy with that collaboration. Dr. Markopoulou does great clinical evaluations and we are getting some very interesting data,” said Rash.
The validation studies are scheduled to be completed later this year, and the company hopes to start selling the test by the end of 2008 in Greece and the U.S., according to its press release. In addition to helping clinicians with diagnosis, Rash hopes the test will help doctors correctly identify patients and controls for clinical trials. “We can also monitor patient progress on a quantitative basis to see if the biomarkers are coming back closer to the norm,” he said. That potential may interest drug developers, as may some of the markers in the panel, which could turn out to be potential drug targets themselves. The research community eagerly awaits data to peruse. Other blood-based diagnostic tests that are at various stages of research and validation include one by the Norwegian company DiaGenic, one by the Belgian company Innogenetics, and one by the Californian startup Satoris (see ARF related news story).—Tom Fagan.
- Goldknopf IL, Sheta EA, Bryson J, Folsom B, Wilson C, Duty J, Yen AA, Appel SH. Complement C3c and related protein biomarkers in amyotrophic lateral sclerosis and Parkinson's disease. Biochem Biophys Res Commun. 2006 Apr 21;342(4):1034-9. PubMed.
- Sheta EA, Appel SH, Goldknopf IL. 2D gel blood serum biomarkers reveal differential clinical proteomics of the neurodegenerative diseases. Expert Rev Proteomics. 2006 Feb;3(1):45-62. PubMed.