BioWorld International Correspondent
LONDON - The prospects for pharmacogenomics have been oversold, and the era of personalized medicine based on gene testing remains more than 15 years away.
That is the conclusion of "Personalized Medicines: Hopes and Realities," a study published last week by the Royal Society, the UK's national academy of science.
As part of the hype around the Human Genome Project, expectations were raised that sequencing the genome would lead within a few years to personalized medicine.
"But the reality is still many years away," the report said. "There are some examples [of applications of pharmacogenomics] around today, but the complex, multiple causes of diseases mean it will be 15 to 20 years before a patient's genetic makeup is a major factor in determining which drugs they are prescribed."
Not only is the development of personalized medicines hampered by the many gaps in understanding of how genetics relates to causes of disease, but also because health care professionals do not have the relevant training, and across Europe there is a shortage of researchers specializing in pharmacogenomics.
The report recommended there be financial incentives to encourage pharmaceutical and biotech companies in Europe to work on pharmacogenomic drugs with relatively small markets.
It also called for preparatory groundwork, such as gathering and collating data on how genetics influence response to existing drugs in a patient population. That would reduce the number of adverse reactions and ensure drugs are given only to patients for whom they will be effective.
To date, pharmacogenomics has had little impact on clinical practice.
The most notable impact has been in testing cancer patients to see if they will benefit from drugs such as Herceptin in treating breast cancer, and Gleevec in treating leukemia.
Genetic testing also is in use in some clinical trials to select likely responders.
There should be more intelligent use of the genetic data companies are beginning to collect during clinical trials, and monitoring should continue once products are on the market, with the aim of linking genetic variability with clinical outcome. The report called for monitoring to be a compulsory extension to the current system of clinical trials.
The gathering and analysis of pharmacogenomic patient data introduce issues of storing the information, access, and to what extent it is anonymous.
Governments need to outline the ethical framework for researchers who will be creating or accessing large patient databases.
Pharmacogenomics might be valuable in fighting diseases such as malaria, tuberculosis and AIDs, but variation in the laws for conducting genetic research makes it difficult to combine data at a pan-national level.
The guidelines and regulation for conducting genetic research across international borders need to be reviewed, said the report.
In the UK, the Department of Health is funding six pharmacogenomic projects, which give a flavor of the complexity and the scale of the research that needs to be carried out before the widespread application of pharmacogenomics.
The largest of those is assessing the importance of CYP2C9 variants in provoking adverse reactions - including serious bleeding - to the commonly administered oral anticoagulant warfarin.
The study will involve the genetic testing and subsequent monitoring of 2,400 patients with cardiovascular disorders who are prescribed the drug. CYP2C9 is a member of the cytochrome P450 family of genes that are involved in the metabolism of genes in the liver.