OBJECTIVES : To: (a) summarize the available pharmacoeconomic evidence assessing the value of genetic testing for cancer drugs with clinically relevant drug-gene associations; (b) determine the quality of the studies that contain this evidence and; (c) discuss the quality of this evidence with respect to the level of evidence of the drug-gene associations.

METHODS : The PharmGKB® database was used to identify cancer drugs with clinically relevant drug-gene associations graded moderate (2A, 2B) or high (1A,1B). A systematic literature review was conducted using these drugs. Cost and effect values from every relevant comparison within the studies were extracted and the incremental cost-effectiveness ratio (ICER) was either extracted or calculated for each comparison. Quality assessment was conducted for each study and qualitative synthesis was used to summarize the data.

RESULTS : The search yielded 2,016 citations, of which 37 studies met the inclusion criteria. The studies were conducted in Asia, Europe, Canada, USA and Mexico and reported cost-utility, cost-effectiveness and cost-minimization outcomes. There was variation across studies in terms of quality. Ninety-five relevant comparisons were identified within the studies; of those that reported cost per life year or cost per quality-adjusted life year (n=58 comparisons), genetic testing strategy was dominant in 21% overall and 42%, 25%, 20%, and 8% in Asia, Europe, Canada, and USA, respectively. Variability was observed in the ICER values regardless of region or drug. Genetic testing strategy was cost saving in 18 out of 20 cost-minimization comparisons.

CONCLUSIONS : Among the cost-effectiveness and cost-minimization studies, genetic testing was dominant for 21% and cost-saving for 90% of the comparisons, respectively. There was mixed evidence regarding the value of genetic testing to guide cancer treatment. For future pharmacoeconomic studies, we recommend prioritizing drug-gene associations that are supported by compelling aggregated evidence from sources such as PharmGKB®.