Early health technology assessments in pharmacogenomics: a case example in cardiovascular drugs.

AIM: To assess the required characteristics (cost, sensitivity and specificity) of a pharmacogenomic test for being a cost-effective prevention of angiotensin-converting enzyme inhibitors induced angioedema. Furthermore, we assessed the influence of only testing high-risk populations. MATERIALS & METHODS: A decision tree was used. RESULTS: With a willingness-to-pay threshold of €20,000 and €80,000 per quality adjusted life year, a 100% sensitive and specific test may have a maximum cost of €1.30 and €1.95, respectively. When only genotyping high-risk populations, the maximum test price would be €5.03 and €7.55, respectively. CONCLUSION: This theoretical pharmacogenomic test is only cost-effective at high specificity, high sensitivity and a low price. Only testing high-risk populations yields more realistic maximum test prices for cost-effectiveness of the intervention.

C1-inhibitor concentrate home therapy for hereditary angioedema: a viable, effective treatment option.

Economic and political factors have led to the increased use of home therapy programmes for patients who have traditionally been treated in hospital. Many patients with hereditary angioedema (HAE) experience intermittent severe attacks that affect their quality of life and may be life-threatening. These attacks are treated with C1-inhibitor concentrate which, for most patients, is infused at the local hospital. Home therapy programmes for HAE are currently being established. This paper reviews the extent of use of these programmes and summarizes the advantages and potential disadvantages of the concept so far.

Increased activity of coagulation factor XII (Hageman factor) causes hereditary angioedema type III.

Hereditary angioedema (HAE) is characterized clinically by recurrent acute skin swelling, abdominal pain, and potentially life-threatening laryngeal edema. Three forms of HAE have been described. The classic forms, HAE types I and II, occur as a consequence of mutations in the C1-inhibitor gene. In contrast to HAE types I and II, HAE type III has been observed exclusively in women, where it appears to be correlated with conditions of high estrogen levels--for example, pregnancy or the use of oral contraceptives. A recent report proposed two missense mutations (c.1032C-->A and c.1032C-->G) in F12, the gene encoding human coagulation factor XII (FXII, or Hageman factor) as a possible cause of HAE type III. Here, we report the occurrence of the c.1032C-->A (p.Thr328Lys) mutation in an HAE type III-affected family of French origin. Investigation of the F12 gene in a large German family did not reveal a coding mutation. Haplotype analysis with use of microsatellite markers is compatible with locus heterogeneity in HAE type III. To shed more light on the pathogenic relevance of the HAE type III-associated p.Thr328Lys mutation, we compared FXII activity and plasma levels in patients carrying the mutation with that of healthy control individuals. Our data strongly suggest that p.Thr328Lys is a gain-of-function mutation that markedly increases FXII amidolytic activity but that does not alter FXII plasma levels. We conclude that enhanced FXII enzymatic plasma activity in female mutation carriers leads to enhanced kinin production, which results in angioedema. Transcription of F12 is positively regulated by estrogens, which may explain why only women are affected with HAE type III. The results of our study represent an important step toward an understanding of the molecular processes involved in HAE type III and provide diagnostic and possibly new therapeutic opportunities.