NEW YORK (GenomeWeb) – With a CHF 1 million ($1.1 million) addition to its Series B financing round announced this week, Swiss proteomics firms ProteoMedix plans to begin clinical validation of its four-protein prostate cancer test.
The company will this year start clinical studies for the test in central Europe, the UK, and the US, enrolling a total of 1,500 patients, Co-founder and CEO Ralph Schiess told GenomeWeb. He added that ProteoMedix hopes to begin commercial roll-out of the test in the next two to three years, launching first in Europe and then in the US.
This marks a shift from the firm's original timeline, which called for a launch of the test sometime in 2015. Schiess said the company pushed this launch date back in order to do more extensive clinical validation, including a prospective trial in the US, before putting the test on the market.
The four-protein panel is intended as an improvement over prostate-specific antigen for determining whether patients suspected of having prostate cancer should undergo biopsies. PSA testing suffers from poor specificity, which leads to large numbers of false positives and unnecessary biopsies, and so, improved prostate cancer diagnostics have been an area of significant focus in molecular medicine.
The ProteoMedix panel is aimed at patients with indeterminate PSA scores of between 2 and 10 nanograms per mL, and based on the results of the test, a recommendation is made as to whether or not a patient should be biopsied. The test uses measurements of four proteins combined with the patient's PSA score. In a 143-patient study published in Proceedings of the National Academy of Sciences in 2011 that is the basis for the test, the four-protein panel detected prostate cancer with an accuracy of 84 percent, compared to 70 percent for PSA alone, and offered specificity of 79 percent compared to 45 percent for PSA alone.
Schiess said that data from a recent 180-patient study suggests that the test could reduce negative biopsies by more than 50 percent.
ProteoMedix was spun out of the lab of Swiss Federal Institute of Technology researcher Ruedi Aebersold in 2010, and in 2011 the company raised CHF 2.6 million in its Series A funding round. Much of this funding was used to convert the markers, which were originally discovered using mass spectrometry, to an immunoassay format. Over the last year, the company has continued to refine these immunoassays, recently getting them to the point, Schiess said, where they are ready for clinical validation.
The CHF1 million raise announced this week is an addition to the CHF 3.2 million Series B round the company closed last April. In the round, a new private investor joined the existing group of investors including Altos Venture, Zürcher Kantonalbank, and several other private investors.
In addition to the four-protein panel for determining whether a patient is likely to have prostate cancer, ProteoMedix is also working on a proteomic test for gauging the aggressiveness of the disease in patients with confirmed cases. Because many prostate cancers are slow developing, some patients can be managed by watchful waiting as opposed to surgical removal of the prostate, which can lead to a variety of side effects.
In September, the company said it was taking part in a research project for the development of such a test funded by CHF1.6 million from Switzerland's Commission for Technology and Innovation.
Schiess said the company is investigating markers identified in the original PNAS study and plans to identify a number of candidate markers for transferring to immunoassays within the next six to nine months.
Both tests will face considerable competition from other proteomic offerings and genomic tests. For instance, Opko Health last year launched US sales of its 4Kscore proteomic test for assessing whether a patient should undergo a prostate biopsy. And companies including Genomic Health, Myriad Genetics, GenomeDx, and Metamark all have genomic or proteomic tests on the market for gauging the aggressiveness of a patients' disease.
On the prognostic front, Schiess said one thing that could help the ProteoMedix test stand out is that, unlike many of its genomic competitors, it is blood-based, which, he said, makes for a more convenient and potentially more accurate test.
"It's well known that there is a bias in taking biopsies," Schiess said. "You might miss the most aggressive part of the cancer [with a biopsy], and by having a blood based test you are really independent of this concern."
"The other thing," he added, "is sampling. If you put a patient on active surveillance, it is much easier to redo testing with a blood-based test than if you have to redo a biopsy every time."
Convenience is also the notion behind ProteoMedix's decision to transfer its panels to immunoassays, Schiess noted. While he said that he felt mass spec is ready for clinical proteomics in the case of certain more specialized tests, "if it is a test that is used for early diagnosis and screening, you need a high-throughput test that is cheap and easily available, and that's still an advantage of immunoassays."
ProteoMedix does not do its mass spec-based discovery in-house, Schiess said, but, rather, collaborates with Aebersold's lab on this work. Aebersold is a co-founder and scientific advisor to the company.