UK, Australia also developed its national framework for assessing personalized
medicine products for the purpose of assisting reimbursement decisions.^26
3.1 The Differences Between the Economic Evaluations
of Drugs and Diagnostics
Economic evaluations of diagnostics share many features with the economic
evaluations of pharmaceuticals, but there are also differences. Both drugs and
diagnostics represent health technologies designed to improve the quality and the
length of life of patients, at a certain cost. However, as Garrison and Towse ( 2014 )
discuss, there are several ways is which personalized medicine technologies
(or companion diagnostics) can create additional value relative to pharmaceuticals.
Notably, they can reduce the patient’s uncertainty about the likelihood of successful
treatment and generate the “value of knowing” as a result. “Value of knowing”
refers to the fact that even if the result of a test does not lead to a change in the
treatment, the value of receiving both the knowledge about the likely result and the
best possible advice given full information carries great merit and value for patients
and for physicians.^27 Moreover, the diagnostic personalized medical tools can
improve adherence and thus the health outcomes for treated patients. Finally,
personalized technologies can raise overall uptake and utilization at the population
level.
According to the UK DAP guidelines for the appraisal of diagnostics, there are
several main differences between conducting economic evaluations for pharma-
ceuticals versus economic evaluations of (companion) diagnostics. These differ-
ences seem to have a common denominator: the quantity and the quality of
available evidence. Indeed, the quantity and quality of evidence about patient
outcomes for diagnostic technologies are typically lower than the evidence avail-
able for drugs. The lower quality and quantity of evidence can be ascribed to several
factors, according to UK DAP guidelines. One factor is the very nature of benefits
(or outcomes) that a diagnostic test produces. For instance, some diagnostic tests
detect risk factors and not the disease itself. This is becoming increasingly common
with genetic tests that do not detect the disease but help to determine the probability
of the disease developing. The benefits stemming from the results of these tests are
confined to modifying risk and risky behavior before the onset of disease or disease
prevention, overseeing patient’s condition, or introducing early treatment following
disease onset, all of which are benefits that are difficult to model. Another important
(^26) Merlin et al. ( 2013 ), pp. 333–342, provide an overview of the Australian guidelines.
(^27) This idea is further discussed by Annemans et al. ( 2013 ), pp. 20–26, and Payne and Annemans
( 2013 ), pp. 32–38.
118 A. Bobinac and M. Vehovec