Personalized Medicine: So Close Yet So Far
Five years ago, I was a starry-eyed admirer of personalized medicine and one of the first in the healthcare communication industry to write an article about this exciting topic. In June, the American Society of Clinical Oncology (ASCO) meeting gave me insights into the complexity and enormity of the challenges just in designing and implementing clinical trials for targeted therapies. No wonder the conversation at ASCO’s 2008 meeting buzzed around just one single marker, the KRAS. No wonder so few targeted therapies have been introduced since the approval of Herceptin® (trastuzumab) ten years ago.
My curiosity about the pace of new product launches took me to the recent Burrill Personalized Medicine Meeting. I got an even better sense of the multitude of scientific, technological, economic, cultural and sociopolitical issues surrounding personalized medicine. I particularly appreciated the insight of Dr. Susan Desmond-Hellmann, president, Product Development, Genentech. She stated that our knowledge of molecular genetics far exceeds what we know about biology, with the latter being the rate-limiting step. Thus, a key reason for the dearth of targeted therapies today is the deficit in our fund of scientific knowledge. Once a target and the corresponding therapy are identified, one of the challenges in therapeutic development is in developing and validating a suitable, robust assay for the target. The financial incentives for the diagnostic and pharmaceutical companies have to be there, as does reimbursement and acceptance by the clinical community.
But targeted therapy is only one component of personalized medicine. Much of the unharnessed power of personalized medicine—defined more broadly as individualized healthcare based on genetic variations—lies in identifying and understanding risk factors and developing a plan for mitigating those risks. This shift toward a focus on wellness from our current mindset of intervention and treatment requires more than a change in attitude among consumers and physicians. It demands new health policies that provide financial rewards for wellness. Toward that end, it will not be surprising to see an increasing role for the consumer as the seeker of the additional information that genetic testing can provide. In fact, recent history with BRCA1 and BRCA2 testing, and now the emergence of companies such as Navigenics and 23andMe, point to consumers’ appetite for personal genetic information and, more important, their willingness to pay. Perhaps the consumer will be the one leading the charge as champion and advocate for personalized medicine?
Genelex has been offering pharmacogenetic testing of the key drug metabolizing enzymes since 2000. This information can help guide better clinical decision making in many areas, and yet the pace of adoption in painfully slow. For instance, 7-10% of the population that are 2D6 PMs will not benefit from tamoxifen treatment, why is this test not widely adopted? One of the biggest barriers we have seen is lack of clinician awareness and understanding of pharmacogenetics and personalized medicine as a whole. We have created a tool, GeneMedRx, that helps clinicians apply pharmacogenetic testing by predicting the cumulative effect of drug-drug and drug-gene interactions. This type of interpretation tool will be needed in all areas for personalized medicine to bridge the interpretation gap.
I agree that lack of clinician awareness and understanding will continue to be a barrier. Randy Scott commented at the Burrill Personalized Medicine Conference that, despite compelling proof of clinical utility, only one-third of breast cancer patients today receive the Oncotype Dx test. Education and training are certainly a necessity. We also have to recognize the “first do no harm” and in many ways risk-averse culture of the clinical community.