Molecular imaging and personalized medicine: an uncertain future.

The Food and Drug Administration has described their view of the role that imaging will play in the approval, and perhaps postapproval, use of new therapeutic drugs. The therapeutic drug industry and regulatory authorities have turned to imaging to help them achieve better efficiency and efficacy. We must extend this initiative by demonstrating that molecular imaging can also improve the efficiency and efficacy of routine treatment with these same drugs. The role of molecular imaging in personalized medicine, using targeted drugs in oncology, is very attractive because of the regional information that it provides (in many cases, with a functional or dynamic component), which cannot be provided by in vitro methods ("regional proteomics"). There is great potential for molecular imaging to play a major role in selecting appropriate patients and providing early proof of response, which is critical to addressing the conflict between the high price of treatment and limited reimbursement budgets. This is a new venture in both molecular imaging and targeted drugs. However, there are various regulatory, financial, and practical barriers that must be overcome to achieve this aim, in addition to the normal scientific challenges of drug discovery. There is an urgent need to reduce the cost (i.e., time and money) of developing imaging agents for routine clinical use. The mismatch between the current regulations and personalized medicine includes molecular imaging and requires the engagement of the regulatory authorities to correct. Therapeutic companies must be engaged early in the development of new targeted drugs and molecular imaging agents to improve the fit between the two drug types. Clinical trials must be performed to generate data that not only shows the efficacy of imaging plus therapy in a medical sense, but also in a financial sense. Molecular imaging must be accepted as not just good science but also as central to routine patient management in the personalized medicine of the future.