It looks like Smith and Hilner have taken up the challenge by creating a top five list of common oncology practices, which if limited to situations where they are truly clinically useful, would sharply lower the cost of cancer care. In many cases, the cost-effectiveness ratios far exceed commonly accepted thresholds, according to Merrill Goozner, of The Fiscal Times. Goozner also wished they had addressed the issue: Why are cancer drugs of marginal efficacy so expensive? Why does a drug that extends life by a month or two cost $5,000 to $10,000 a month for the last year or two of a patient's life, thus adding up to a quarter million dollars to the cost of end-of-life care?
The challenge facing pharmacogenetics – the study of genetically determined variations in responses to drugs in humans – is the number and complexity of interactions a drug has with biological molecules in the body. Variations in many different molecules may influence how someone responds to a medicine. There is a great degree of variation in how people absorb drugs. Individuals have different levels of enzymes in the intestines and liver that breaks down drugs before they even have the chance to get into the bloodstream.
Teasing out the genetic patterns associated with particular drug responses could involve some intricate and time-consuming scientific detective work. Unfortunately, the introduction of these new drugs has not been accompanied by specific predictive tests allowing for a rational and economical use of the drugs. However, there are a number of laboratory tests that are better able to predict the ability of targeted drugs, to produce positive clinical responders (outcomes). To exploit the full potential of targeted anticancer therapies, physicians need laboratory tests that actually match patients to specific drugs.
No pharmaceutical company relishes turning over sizeable pieces of profitable business because a diagnostic test suggests it should. An article in Pharmaceuticalcommerce.com
, Drew Fromkin, CEO of Clinical Data warned us that drug makers must drive growth, revenue, and profitability, and personalized medicine runs against their prevailing business model. But many realized that personalized treatments were inevitable and tried to find their way within a new paradigm.
In cancer medicine, that new paradigm established a requirement of a companion diagnostic as a condition for approval of these new targeted therapies. However, it put such great pressure that the companion diagnostics that were approved often had been mostly or totally ineffective at identifying clinical responders to the various therapies. That is because genomics are far too limited in scope to encompass the vagaries and complexities of human cancer biology.
However, Fromkin believed that the impetus for personalized medicine would come from payors, not drug firms. Insurers were paying for drugs that do not provide value, and have been desperate to eliminate the shotgun approach to cancner medicine. But how would drug companies respond when these tests show their drug to be highly effective, but only in 11% of the potential patient population? What can medicine offer patients whose test results suggest no medicine will help?
A $1.5-billion-a-year drug is a blockbuster. Five $300-million drugs, taken together, do not add up. Unless the costs for developing a $300-million new chemical entity can be harmonized with the expected financial return, no one will develop such drugs. Charging significantly more for targeted therapies will work only to a point.
Given the technical and conceptual advantages of Oncologic In Vitro Chemoresponse Assays, together with their performance and the modest efficacy of therapy prediction based on analysis of genome expression, there is reason for a renewal in the interest for these pre-tests for optimized use of medical treatment of malignant disease.