Although the concept of companion diagnostics is compelling, progress to the market has been slow as they require extensive collaboration between diagnostic and drug companies. There are a myriad of political, scientific, and regulatory issues stymieing progress, including whether drug firms can expend the time and money to develop biomarkers in parallel with drugs; developing a robust, reliable assay; dealing with the fact that many proposed markers are run in CLIA labs and are not approved diagnostic kits; and onerous regulatory pathways.
Another major challenge for biomarker discovery and evolution to a diagnostic kit is proving clinical utility and the major investment in clinical trials. Stephen Little, Ph.D., vp of personalized healthcare at Qiagen, estimated that a Phase III drug trial can cost $100 million and a companion diagnostic for the same indication could cost as much as $20 million more. The available market for an FDA-approved companion diagnostic is likely to be between $20 and $50 million a year.
John Schultz, senior vp of licensing and strategic development at Clinical Data, pointed out during “BIO” that IP ownership can also crop up as problem. Yet another point of consideration is which assay platform should be used, which affects pricing, said Schultz. Most biomarker platforms utilize nucleic acid testing such as PCR and immunoassays. Mass spectrometry for SNP genotyping also shows promise for prenatal diagnostics; this forms the basis of Sequenom’s diagnostics.
DNA microarrays are also gaining ground, and Illumina recently reported 510(k) market clearance for its BeadXpress System for in vitro diagnostic use only with the VeraCode Genotyping Test for Factor V and Factor II.
DNA sequencing for genomic research is growing quickly as the cost of personal human genome sequencing makes its way down toward the $1,000 mark.
Finally, Schultz noted that it is important to determine how the diagnostic can be marketed. Biomarkers have the potential to be transformative, but the business model has not yet been proven. According to Dr. Little, three possible business models include: a biomarker gets accepted as part of the drug development process; payors drive the evolution of a product when it becomes clear that a subpopulation can be targeted for improved drug efficacy and cost effectiveness; and patients pursue tests where they can obtain test data for their own treatment.