Ethics and Pharmacogenomics, does one size fit all ?
In
the last decade, new techniques in genetics have provided powerful
and potentially inexpensive tools for studying the genetic basis of
such differences in drug response on a large scale. The mapping of the human genome
and the technology that made it possible opened up a new vision, in
which individual patients could be tested for a host of relevant
genetic differences, and the results could be used to choose the safest
and most effective compound for each patient - finding each person's
'very own medicine'. This poses new challenges for public policy
makers.
Uses of genetic testing for drug choice
Genetic testing of individual patients to guide drug treatment choices in clinical settings is referred to as pharmacogenetics.
There are three main potential uses of genetic tests in guiding
individualised drug treatment: -To adjust doses -To choose the most
effective drug for a particular individual -To avoid serious adverse events due to individual metabolic idiosyncrasies" (See Quotation source*) However, such testing has major ethical, legal and social implications.
The Cambridge Genetics Knowledge Park (CGKP)
The Cambridge Genetics Knowledge Park (CGKP) is one of
six in England and Wales, funded by the Genetics Knowledge Challenge
Fund established by the Department of Health
and the Department of Trade and Industry and focuses on these ethical,
legal and social implications. The Five sectors of genetics knowledge:
Clinical; Commercial; Ethical, Legal and Social; Scientific; and Public
Health are brought together within the Cambridge Genetics Knowledge
Park for the benefit of society (right).
Ethical issues in patients' consent to pharmacogenomic trials
Blood samples are currently being collected from patients participating in clinical drug trials,
to be used for pharmacogenomics research. While there has been a great
deal of attention given to the collection of blood samples for use in
public genetic databases, there has been virtually no discussion of the
formation of such databases by or on behalf of the pharmaceutical
industry. In pharmacogenomics studies, patients are asked to consent to
three separate aspects of research: the main clinical drug trial,
research involving a specific genetic test related to a drug effect,
and unspecified genetic tests to be used in future pharmacogenetics
research. They give the sponsoring pharmaceutical company permission to
link genetic research on their blood sample to personal medical
information, such as details of their medical condition and family
history. It may be suggested that the limits of consent for
pharmacogenomics studies are being overreached.
Given evidence of the inability of patients who have decided to
take part in clinical trials to comprehend information about trial
procedures or to recall information about potential risks, it is
possible that patients entering into pharmacogenomics related trials
may not have given careful consideration to all potential risks and
benefits of this additional research. Patients who already feel
overburdened with information and anxiety, and in a weakened position
to make independent decisions, may be exploited in this situation.
Although in conventional clinical drug trials patients are subjected to
additional risks over and above conventional therapy, patients have at
least the possibility of benefiting either from the comparative drug
being tested or from the trial drug. By contrast, there is no direct
benefit to the patient in the pharmacogenomics study and thus
compromises in the consent process cannot be offset against potential
therapeutic benefit. As against this, it could be argued that the risks
are much smaller than those accepted in conventional therapeutic
trials. genetic testing
during the pharmacogenomics part of a clinical trial may potentially
be extremely valuable commodities for genetic-based drug development.
In addition to their consent to take part in the research, patients are
required to agree in writing that they have no property rights over
the sample or any data generated from it. These considerations all
raise profound questions about the meaning of consent for
pharmacogenomics trials. Should patients be financially rewarded for
their involvement, as is the case for healthy subjects in Phase I
trials and for the physicians who recruit, conduct and oversee clinical
trials? Or should the fact that patients in the main trial are likely
to receive benefit in the form of therapy be sufficient reward for
taking part in additional pharmacogenetics research? Is it right that
participants be excluded from taking a financial interest in products
that have been developed using their blood or tissue? And to what
extent should altruistic reasons on the part of patients be taken into
consideration? While pharmaceutical companies are foremost
profit-making organisations and economic generators, they are also the
vehicle by which successive governments have chosen to develop and test
new drugs. We are thus left with the challenge of determining how to
regulate clinical drug trials and pharmacogenomics research in a way
that better protects patients and research subjects, but does not
overly restrict potential medical breakthroughs.
Following
the US case of John Moore, a patient whose cell-line was patented and
sold to the drug company Sandoz for $15 million, issues of property
rights are increasingly being raised in relation to tissue samples.
Blood samples that are donated for
About the authors:
Acknowledgements: The Wellcome Trust's Biomedical Ethics Programme sponsored Oonagh's research.
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