Pharmacogenomics is the study of the influence of genetic factors on drug response.

The goals of pharmacogenomic research are: a) to study the interactions between genetic factors and response to treatment and/or b) to identify new targets for treatments. For example, pharmacogenomics research may explore whether the presence of a particular version of a gene influences the effectiveness or the side effects of a given medication. Another example is a study that seeks to identify the genes involved in the response to medications.

At this time in Canada, pharmacogenomic testing is not required for drug approval or in the prescription process. However, the development of practices involving the voluntary submission of pharmacogenomic information draws attention to the importance that such information could have in the future.

Two terms are used by experts to describe this type of research: pharmacogenomics and pharmacogenetics. These two terms are sometimes used synonymously and are sometimes used to refer to distinct concepts. Several definitions have been ascribed to each and there is no consensus on what each of them mean. In this FAQ, we use the term pharmacogenomics only.

Genetic differences among individuals are proven to contribute to their drug treatment response. Pharmacogenomic research could lead to the identification of new targets for treatments and to a better understanding of the mechanisms of action for treatments. It could also reduce cost and time in the development of new medications, as well as ensure better follow-up once treatments have hit the market. There is hope that pharmacogenomics will one day allow for the identification of those people for whom a treatment will either be effective or have no side effects. This will allow the possibility of putting medication targeted to specific groups of people on the market.

In Canada, pharmacogenomics is primarily only in the research phase. Clinical application, except in rare cases, is not yet underway.

One such rare case involves the pharmacogenomic drug, Herceptin, which is used to treat some forms of breast cancer. For women who have developed this type of breast cancer, the treatment is very effective, but for others who have developed another form of breast cancer, the treatment has no effect.

• Genetic factors are not the only influence on drug response. Environment and lifestyle are also important factors.
• The application of pharmacogenomics requires the existence of rapid, reliable, and inexpensive genetic tests.
• The clinical relevance of genetic variations must be proven.
• Applications are currently limited to a specific number of treatments for a limited number of illnesses.
• Health professionals, including doctors, nurses, genetic counselors, and pharmacists, will need to receive training before pharmacogenomics is integrated into medical practice.

An article in the editorial GenEdit entitled Consent in Pharmacogenomic Research (2007) reveals that there are few policies in this domain and specifies the importance of establishing a clear international framework in order to guide researchers in pharmacogenomics.

• In 2007, the final version of the ICH Harmonized Tripartite Guideline, E15: Definitions for Genomic Biomarkers, Pharmacogenomics, Pharmacogenetics, Genomic Data and Sample Coding was approved. This directive defines, among other things, the terminology of pharmacogenomics (for example, concepts around samples and information, such as identified, coded, double coded, anonymized, etc).
• The statement of the Human Genome Organisation’s (HUGO) ethics committee, entitled HUGO Statement of Pharmacogenomics (PGx): Solidarity, Equity and Governance contains recommendations related to the governance of pharmacogenomic research. This directive emphasizes the importance that research be guided by a concern for equity rather than solely for financial interests. It also articulates the importance of developing good governance practices so that research is carried out in an effective manner and in the best interests of the community.
• Other groups have published policies on pharmacogenomics, including the Nuffield Council on Bioethics (UK), the Pharmacogenomics Working Group and the Consortium on Pharmacogenomics. The ideas that are found in these documents could serve as an inspiration for the development of a complete ethical framework for researchers in pharmacogenomics.

• Similar to the FDA in the United States, Health Canada has developed a guidance document, Submission of Pharmacogenomic Information (2007), concerning the voluntary submission of pharmacogenomic data. This document suggests that separate consent should be obtained when a pharmacogenomic study takes place in the context of a clinical trial.
• In addition to explaining the pharmacogenomic study, consent forms must also inform participants “that pharmacogenomic testing will be conducted and the research aim, the sample and data coding strategy, and the storage, destruction and security measures used around sample and data preservation.” Other requirements may be outlined by the ethics review committee reviewing the research.

There is no regulatory framework in Quebec unique to pharmacogenomic research. Quebec researchers rely on national and international guidelines (for example, the Tri-Council Policy Statement) as well as on the provisions of the Civil Code of Quebec governing research involving human subjects to guide them in the ethical, legal, and social aspects of their research.

When pharmacogenomic research involves children, certain ethical issues must be underlined.

Parental consent to pharmacogenomic research and children’s assent can be complicated due to the complexity of the information that needs to be transmitted. The complexity of this type of research can make explaining information to children difficult. Ultimately, this could affect their assent to participate in research.

Communicating results to children raises some questions such as: who should receive the results (the child, his/her legal representative, his/her doctor, or someone else?) and in what manner? These questions are particularly important because the information could have an impact on a child’s clinical care. They could also have an impact on the family. Should the information be provided to the child’s parents? When a child is mature, should the results be communicated to them? This could lead to problems around communication of results because the child may have forgotten that he/she participated in the research or may no longer be a minor.

Pharmacogenomic research in children could lead to the formation of a new orphan disease group. This would occur where pharmaceutical companies fail to develop pharmacogenomic treatments for children because developing these treatments for only a small group would be an economic disincentive. As a result, children would not benefit from the promise of pharmacogenomic developments. American and European legislation has put provisions in place in the hope of promoting treatment development for children and orphan disease groups.