Health technology assessment in the era of personalized health care.

OBJECTIVES: This article examines the challenges for health technology assessment (HTA) in the light of new developments of personalized health care, focusing on European HTA perspectives. METHODS: Using the example of the Integrated Genome Research Network - Mutanom (IG Mutanom) project, with focus on personalized cancer diagnostics and treatment, we assess the scope of current HTA and examine it prospectively in the context of the translation of basic and clinical research into public health genomics and personalized health care. RESULTS: The approaches developed within the IG-Mutanom project are based on innovative technology potentially providing targeted therapies for cancer; making translation into clinical practice requires a novel course of action, however. New models of HTA are needed that can account for the unique types of evidence inherent to individualized targeted therapies. Using constructive health technology assessment (CTA) models is an option, but further suitable models should be developed. CONCLUSIONS: Integrative, systems biology-based approaches toward personalized medicine call for novel assessment methods. The translation of their highly innovative technologies into the practice of health care requires the development of new HTA concepts.

CYP2D6 genotyping for psychiatric patients treated with risperidone: considerations for cost-effectiveness studies.

In order to ascertain data availability and feasibility for conducting cost-effectiveness studies in pharmacogenetics, and as part of a European Commission Joint Research Center, Institute for Prospective Technological Studies (JRC-IPTS) study, data concerning risperidone use and cytochrome P450 (CYP2D6) genotyping in medical care was collected in Germany, Spain and the USA, and are summarized in this perspective. The gene coding for CYP2D6 is highly polymorphic, resulting in a significant part of the population being poor metabolizers and ultrarapid metabolizers. Individuals who are CYP2D6 poor metabolizers, have an increased risk of adverse drug reactions (ADRs) when treated with CYP2D6-metabolized drugs, suggesting that CYP2D6 genotyping might be beneficial for patient care. This might be especially important in psychiatry, where approximately 50% of the patients use at least one drug primarily metabolized by CYP2D6. In particular, ADRs and poor response to treatment are major problems for some antipsychotics, including risperidone. However, there are no published cost-effectiveness studies on CYP2D6 genotyping, and the benefit that pharmacogenetic testing might represent by identifying problematic patients is still unclear. The present European Commission study found that current clinical and economical data concerning the frequency and direct healthcare costs of risperidone-related ADRs, the relation of such ADRs with the patients CYP2D6 genotypes, and costs for CYP2D6 genotyping, are not sufficient for determining if routine CYP2D6 genotyping might be cost beneficial for patients treated with risperidone. Therefore, efforts should be put on performing prospective cost-benefit studies with randomized treatment according to the CYP2D6 genotype to establish the utility of CYP2D6 genotyping for personalizing antipsychotic treatment.

Ancestry in translational genomic medicine: handle with care.

Disparities in health outcomes of members of different ancestral or ethnic groups can be observed in both developed and developing countries and continue to be a global concern. Genomic medicine can help toward closing this gap by expanding the knowledge on novel alleles related to disease risk and drug response, their frequencies, and their relation with disease and drug-response phenotypes, in as many countries and ethnic groups as possible. Without such knowledge, genomic medicine cannot deliver upon its promise of contributing to health for all. However, the use of ancestry or ethnicity-related genetic information as a selection criterion for assigning varying levels of access to health care is condemnable. Translational genomic medicine will allow for individualized clinical decision making - doing away with the use of race, ethnicity or ancestry as a proxy.

Personal genomics services: whose genomes?

New companies offering personal whole-genome information services over the internet are dynamic and highly visible players in the personal genomics field. For fees currently ranging from US$399 to US$2500 and a vial of saliva, individuals can now purchase online access to their individual genetic information regarding susceptibility to a range of chronic diseases and phenotypic traits based on a genome-wide SNP scan. Most of the companies offering such services are based in the United States, but their clients may come from nearly anywhere in the world. Although the scientific validity, clinical utility and potential future implications of such services are being hotly debated, several ethical and regulatory questions related to direct-to-consumer (DTC) marketing strategies of genetic tests have not yet received sufficient attention. For example, how can we minimize the risk of unauthorized third parties from submitting other people's DNA for testing? Another pressing question concerns the ownership of (genotypic and phenotypic) information, as well as the unclear legal status of customers regarding their own personal information. Current legislation in the US and Europe falls short of providing clear answers to these questions. Until the regulation of personal genomics services catches up with the technology, we call upon commercial providers to self-regulate and coordinate their activities to minimize potential risks to individual privacy. We also point out some specific steps, along the trustee model, that providers of DTC personal genomics services as well as regulators and policy makers could consider for addressing some of the concerns raised below.

Improving pharmacovigilance in Europe: TPMT genotyping and phenotyping in the UK and Spain.

Thiopurine S-methyltransferase (TPMT) is the rate-limiting step in the conversion of thiopurine drugs including azathioprine (AZA) to inactive metabolites. Heritable deficiency of TPMT activity increases risk for adverse events, most notably, myelosuppression leading to leukopenia and neutropenic sepsis. The reported European Commission study was undertaken to identify current evidence for the clinical utility of testing for TPMT status and extent of uptake, by either genotyping or phenotyping, in the clinical setting. Data presented here for the UK and Spain indicate that there has been a considerable increase in the uptake of TPMT testing in recent years. There are some data that support routine TPMT testing before AZA prescribing for reducing AZA-related adverse events. Key data include evidence in favor of TPMT testing in addition to the current practice of routine monitoring for reducing the number of AZA-related episodes of myelosuppression, averting deaths from neutropenic sepsis and improving health-related quality of life. Further data are needed for determining the cost-effectiveness of routine TPMT testing.

TPMT testing in azathioprine: a 'cost-effective use of healthcare resources'?

This study aimed to critically appraise the current level of economic evidence available for thiopurine S-methyltransferase (TPMT) testing of thiopurine drugs, such as azathioprine. Six economic evaluations of testing were identified, which all recommended that TPMT testing is a cost-effective use of healthcare resources. Critical appraisal, using published guidelines, showed potential limitations in model structures, approaches to data analysis and input parameters, which were mainly based on expert opinion. Where data did exist these were from retrospective studies. To conduct economic evaluations with more robust findings, decision analysts need good quality data for the following key parameters: current prevalence of profound neutropenia among patients prescribed thiopurine drugs; mean length of related hospitalization and clinical outcome; impact of introducing the test on clinical pathways in terms of resource use; and clinical effectiveness data in terms of number of cases of neutropenia averted and subsequent impact on mortality and health-related quality of life. An iterative approach may be used to stimulate the production of a sufficient evidence base for innovative technologies, such as pharmacogenetic testing. Such an iterative approach involves starting with simple models using available existing clinical and resource use data, as in the case of TPMT testing. The use of formal value of information methods may guide the decision whether prospective studies are required to address uncertainties in the key parameters driving the model results. The results from well-designed prospective studies can then be used to populate more complex economic models.

Cost-effectiveness of pharmacogenomics in clinical practice: a case study of thiopurine methyltransferase genotyping in acute lymphoblastic leukemia in Europe.

Only a few studies have addressed the cost-effectiveness of pharmacogenetics interventions in healthcare. Lack of health economics data on aspects of pharmacogenetics is perceived as one of the barriers hindering its implementation for improving drug safety. Thus, a recent Institute for Prospective Technological Studies (IPTS) study, entitled 'Pharmacogenetics and pharmacogenomics: state-of-the-art and potential socio-economic impact in the EU' included an explorative cost-effectiveness review for a pharmacogenetic treatment strategy compared with traditional medical practice. The selected case study examined the cost-effectiveness of thiopurine methyltransferase (TMPT) genotyping prior to thiopurine treatment in children with acute lymphoblastic leukemia (ALL). Information for the cost-effectiveness model parameters was collected from literature surveys and interviews with experts from four European countries (Germany, Ireland, the Netherlands and the UK). The model has established that TPMT testing in ALL patients has a favorable cost-effectiveness ratio. This conclusion was based on parameters collected for TPMT genotyping costs, estimates for frequency of TMPT deficiency, rates of thiopurine-mediated myelosuppression in TPMT-deficient individuals, and myelosuppression-related hospitalization costs in each of the four countries studied. The mean calculated cost per life-year gained by TPMT genotyping in ALL patients in the four study countries was euro 2100 (or euro 4800 after 3% discount) based on genotyping costs of euro 150 per patient. Cost per life-year gained is expected to further improve following the introduction of the wider use of TMPT genotyping and the availability of lower cost genotyping methods. Our analysis indicates that TPMT genotyping should be seriously considered as an integral part of healthcare prior to the initiation of therapy with thiopurine drugs.

Biochemical and pharmacological characterization of the serotonin transporter in human peripheral blood lymphocytes.

The serotonin transporter (5-HTT) plays a critical role in the termination of serotonin neurotransmission and represents the prime target for selective serotonin reuptake inhibitors (SSRIs). In the present study, the 5-HTT protein in human peripheral blood lymphocyte was characterized pharmacologically and biochemically. The tricyclic antidepressant drug [(3)H]imipramine, an established ligand for the neuronal and platelet 5-HTT, bound saturably and reversibly to a single population of non-interacting binding sites in fresh human peripheral blood lymphocytes. The affinity of [(3)H]imipramine (K(d)) to the transporter, calculated from association and dissociation kinetic experiments, was similar to that obtained from the equilibrium study. The function of the transporter was studied using high affinity [(3)H]5-HT uptake into fresh lymphocytes. [(3)H]Imipramine binding and [(3)H]5-HT uptake were inhibited by tricyclic antidepressants as well as by SSRIs. Western blot analysis as well as immunoprecipitation analysis revealed labeling of a single protein band of approximately 100 kDa. The presence of the 5-HTT in easily accessible nucleated cells such as peripheral blood lymphocytes might permit molecular genetic studies in mood and anxiety disorder patients, and might enhance the understanding of the different efficacies of antidepressants in depressed patients.