Feng, Xiaodong_ Xie, Hong-Guang - Applying pharmacogenomics in therapeutics-CRC Press (2016)

272 Applying Pharmacogenomics in Therapeutics
• Pharmacogenomics (PGx) promises to improve healthcare outcomes of the
patient by increasing drug safety and efficacy in patient care, but it cannot
be assumed to be cost-effective if relevant economic evaluation is not available
in terms of potential additional costs and benefits as a result of genotyping.
Therefore, a PGx-based intervention needs to answer a key question
of whether or not it provides the patient with improved healthcare outcomes
at a reasonable additional cost when compared with conventional strategies.
• The term pharmacoeconogenomics, coined in this chapter, refers to the
study of economic evaluation of the PGx intervention in terms of the fact
that the PGx component has been incorporated into the research field of
pharmacoeconomics.
• Not all patients would benefit cost-effectively from only genotype-guided
medications.
• Marked cost-effectiveness would more likely be anticipated for the drug
whose therapeutic window is narrow, whose treatment response is highly
variable among individual patients, and whose indications are severe
chronic diseases that are difficult to treat or to measure.
• Information on pharmacoeconogenomics should be detailed in drug labeling
and be updated over time.
INTRODUCTION
The marketed drug or medication is a class of special goods that is approved to
treat, prevent, or diagnose diseases. Currently, disease-burden and healthcare
spending have risen at meteoric rates throughout the world because of scarce
health resources; upward-spiraling costs of technological innovation; rapidly
escalating costs of drug research and development (R&D); gradually declining
R&D productivity; increased demands for evidence of safety and efficacy
when a new drug is approved; widening gaps in the ratio of R&D successes
to failures; relatively shorter patent exclusivity periods; and fast-growing global
populations, in particular, the aging populations (who often need polypharmacy).
Therefore, evaluation of the costs and benefits of healthcare has become increasingly
important in the management and distribution of limited resources. In other
words, economic considerations are of paramount importance for optimal choice
of the drug and dosage in patient care. A large number of clinical research studies
have well documented that the cost has become a common barrier to the widespread
use of an expensive new drug, medical innovation, or biological technology
in clinical settings. 1 Therefore, better safety, higher efficacy, and lower costs
have been widely accepted to be the gold standard of optimal drug therapy. 2–6
In short, pharmacoeconomics comes of age. 4
Optimal drug therapy is desired to be cost-effective (less costly and more effective).
Pharmacogenomics (PGx) promises to improve healthcare outcomes of the
patient by increasing drug efficacy and minimizing adverse drug reactions. PGx
testing performance is a critical factor that could affect cost-effectiveness of drug
therapy in terms of potential additional costs and benefits as a result of genotyping. 7
Although PGx-based personalized medicine has the potential to increase drug