Pharmacoeconomic analysis of thiopurine methyltransferase polymorphism screening by polymerase chain reaction for treatment with azathioprine in Korea

Rheumatology (Oxford). 2004 Feb;43(2):156-63. doi: 10.1093/rheumatology/keh001. Epub 2003 Aug 15.


Objectives: To evaluate the value of genotype-based dosing by polymerase chain reaction (PCR)-based polymorphism screening in terms of cost-effectiveness for treatment with azathioprine in Korea.

Methods: Decision analysis was employed to compare a genotype-based dosing strategy with the conventional weight-based dosing strategy using a hypothetical cohort composed of rheumatoid arthritis and systemic lupus erythematosus patients. The time horizon was set up as 1 yr. Direct medical costs were used. Data used were obtained from previous reports, except for PCR and admission costs, which were from real cases. Cost-effectiveness analysis was conducted from a societal perspective. Outcomes were measured as a total expected cost and an incremental cost-effective ratio.

Results: In the base case model, total expected cost and the probability of not dropping out owing to serious adverse events of the conventional weight-based dosing and the genotype-based dosing strategy were 1339 x 10(3) Korean won (1,117 US dollars) and 1109 x 10(3) Korean won (926 US dollars), and 97.06 and 99.90%, respectively.

Conclusions: Our model suggests that a genotype-based dosing strategy through PCR-based thiopurine methyltransferase (TPMT) polymorphism screening is less costly and more effective than the conventional weight-based dosing strategy in Korea, as it was associated with a marked reduction in the number of serious adverse events.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antirheumatic Agents / administration & dosage*
  • Antirheumatic Agents / adverse effects
  • Arthritis, Rheumatoid / drug therapy
  • Arthritis, Rheumatoid / economics
  • Arthritis, Rheumatoid / genetics
  • Azathioprine / administration & dosage*
  • Azathioprine / adverse effects
  • Cost-Benefit Analysis
  • Decision Trees
  • Direct Service Costs
  • Drug Administration Schedule
  • Genetic Testing / economics*
  • Genetic Testing / methods
  • Humans
  • Immunosuppressive Agents / administration & dosage
  • Immunosuppressive Agents / adverse effects
  • Korea
  • Lupus Erythematosus, Systemic / drug therapy
  • Lupus Erythematosus, Systemic / economics
  • Lupus Erythematosus, Systemic / genetics
  • Methyltransferases / genetics*
  • Polymerase Chain Reaction
  • Polymorphism, Genetic*


  • Antirheumatic Agents
  • Immunosuppressive Agents
  • Methyltransferases
  • thiopurine methyltransferase
  • Azathioprine