Table 2. Drugs for which a PGx-guided strategy was studied in economic evaluation(s).
| Drug | Therapeutic area | Gene | Notes (based on PharmGKB.org37) | Number of reviewed publications |
|---|---|---|---|---|
| Abacavir | HIV | HLA-B | Abacavir is contraindicated for HLA-B*5701 carriers as they are at high risk of hypersensitivity reaction. | 5 (refs 37, 38, 39, 40, 41, 42) |
| Azathioprine | Rheumatology | TPMT | Carriers of one nonfunctional TPMT allele may require reduced azathioprine dose. Carriers of two nonfunctional TPMT alleles are at high risk of myelotoxicity and alternative treatment should be considered. | 9 (refs 43, 44, 45, 46, 47, 48, 49, 50, 51) |
| Carbamazepine | Neurology | HLA-B, HLA-A | Carbamazepine is contraindicated for HLA-B*1502 carriers as they are at high risk Stevens–Johnson syndrome/toxic epidermal necrolysis. HLA-A*3101 has also been associated with hypersensitivity reactions. | 4 (refs 21, 52, 53, 54) |
| Citalopram | Psychiatry | CYP2C19, 5-HTTLPR a, HTR2A a | CYP2C19 poor metabolizers require reduced citalopram starting dose. Polymorphisms in 5-HTTLPR and HTR2A are associated with citalopram response.55, 56 | 3 (refs 57, 58, 59) |
| Clopidogrel | Cardiology | CYP2C19 | CYP2C19 poor metabolizers have reduced response to clopidogrel and alternative treatment should be considered. | 6 (refs 25, 26, 60, 61, 62, 63) |
| Clozapine | Psychiatry | CYP2D6, H2 a, 5-HTT a, 5-HT2Aa, 5-HT2Ca | CYP2D6 poor metabolizers may require reduced clozapine dose. Six polymorphisms in H2, 5-HTT, 5-HT2A and 5-HT2C are associated with clozapine response.64 | 1 (ref. 65) |
| Irinotecan | Oncology | UGT1A1 | Patients homozygous for the UGT1A1*28 allele are at higher risk of neutropenia and should receive a reduced starting dose of irinotecan. | 3 (refs 66, 67, 68) |
| Mercaptopurine | Oncology | TPMT | Carriers of one nonfunctional TPMT allele may require reduced mercaptopurine dose. Carriers of two nonfunctional TPMT alleles are at high risk of myelotoxicity and alternative treatment should be considered. | 1 (ref. 69) |
| Warfarin | Cardiology | CYP2C9, VKORC1 | Genetic variation in VKORC1 and CYP2C9 explain 40% variance in warfarin dose. Genetic and clinical information can be used to determine starting dose. | 12 (refs 22, 23, 24, 30, 70, 71, 72, 73, 74, 75, 76, 77) |
Abbreviation: PGx, pharmacogenetics.
a
Gene not mentioned on FDA drug label but appears in economic evaluations.