Response to the letter to the editor.

First of all, the authors are grateful for the comments [1] regarding the study “Cost-utility of talazoparib monotherapy treatment for locally advanced or metastatic breast cancer in Spain” [2]. It is certainly true that it would have been advisable to carry out the analyses with the updated data from the Litton study (2020) [3]. However, considering the results of the incremental cost-effectiveness ratio €252,420.04/QALY, the non-existence of significant differences in overall survival (HR 0.848; 95% CI: 0.670–1.073; p = 0.17) [1] and the low number of participants that were followed for more than 43 months, the authors believe that the modification of the proposed time horizon will not have a significant impact on the results. In addition, it should be taken into account that projecting the effects over time does not improve efficiency, since costs would increase simultaneously.

The authors agree on the need to adjust for overall survival for subsequent lines. However, this could introduce differences in the study population and its characteristics, in addition to moving away from the Spanish healthcare practice, which was the objective of the study.

The authors agree on the methodological limitation of the data obtained from the Ettl (2018) [4] to be used in an economic evaluation and this is reflected in the discussion. As it appears in the methodology section, these data were used in the sensitivity analysis; since the utility values from the systematic review performed by Paracha (2016) [5] were used as the base case scenario.