OBJECTIVES: To evaluate the cost effectiveness of Pertuzumab plus Trastuzumab and docetaxel (PTD) vs. Trastuzumab and docetaxel (TD) for the first-line treatment in patients with HER2+ metastatic breast cancer in Colombia.

METHODS: For the evaluation of the cost-effectiveness a health economic area under the curve model was developed. The model considers three health states: progression-free survival, disease progression and death. The proportion of patients in each health state were derived using patient level data from the CLEOPATRA trial like efficacy and safety results, with the exception where overall survival (OS) utilized data from longer term clinical registries. So far three interim analyses of the CLEOPATRA trial have been conducted. 

RESULTS: The outcomes over a time horizon show an increase in mean OS time for patients assigned to the PTD group as compared to those in the TD of 0.72 years. Mean QALYs are also higher in the PTD group than in the TD group 0.58 QALYs. The addition of Pertuzumab leads to higher total average treatment costs of $143.529 dollars per patient compared to the TD group. These findings result in an ICER of $200.509 per life year gained and of $249.582 per QALY gained. After contrast it with the results of ESMO these show that was obtained an increase in mean PFS time (2.68 vs 1.77 years) and increase mean OS (4.86 vs 3.76 years) to PTD and TD respectively. Mean QALYs are also higher in the PTD group than in the TD group (2.94 vs. 2.37 QALYs), but after ESMO results QALY was (3.37 vs 2.51 years) to PTD and TD. CONCLUSIONS: When compared to commonly accepted cost-effectiveness thresholds, these results exceed commonly applied willingness-to-pay thresholds, but Pertuzumab becomes a therapeutic alternative that offers a better health outcome.