The projected lifetime costs were EUR 3,983 with no intervention, EUR 34,771 with KRAS then BRAF, EUR 35,361 with KRAS, and EUR 38,662 with no testing (cetuximab for all). The QALYs were 0.4430 with no intervention, 0.934 with KRAS then BRAF, 0.936 with KRAS, and 0.947 with no testing.
The incremental cost per QALY gained was EUR 62,653 with KRAS then BRAF, compared with no intervention, EUR 313,537 with KRAS, compared with KRAS then BRAF, and EUR 314,588 with no testing, compared with KRAS.
The most influential inputs were the overall survival of patients with the wild-type KRAS mutation, who were on best supportive care, and the utility value for progressive disease. The ranking of the strategies was unaffected by changes in the model inputs.
KRAS then BRAF testing was the preferred strategy over a willingness-to-pay range of EUR 10,000 to EUR 40,000. Above EUR 40,000 per QALY, KRAS was the preferred strategy.