Bioequivalence has become a standard request for drug commercialization in most high income countries, and significant efforts have been made to implement it in many low and middle income countries. In Chile, the requirement of bioequivalency has been gradually implemented since 2008, associated to a communicational campaign to inform the general population about its scope and importance. The objective of this study is to estimate the effect of the implementation of bioequivalence on the prices of products that have been affected by this policy. We conducted a difference in difference study in a set of 30 chronic use drugs, selected from the eighty clinical guidelines published by the Chilean Ministry of Health. The effect was assessed according to the date when the corresponding ministerial decree was published. A control drugs was selected for each analyzed medication in order to estimate the effect of implementation independently of other factors of the market.

We identified three groups of drugs:

(i) those which experimented a significant increment of price due to bioequivalence; (ii) those where prices decreased; and (iii) those where prices did not (significantly changed) decrease. A sensitivity analysis complemented the study results and identified the significant effect of the date when the bioequivalence was implemented. It is concluded that the implementation of bioequivalence in Chile had a significant effect on prices of some medications. However, the magnitude and direction of such effect depends on the characteristics of the particular market defined by each drug.(AU)