Objectives: To describe changes in the private market for selected originators, branded generics ('similares'), and generic products during the 10 years following passage of the Brazilian Generics Law.

Methods: We analyzed longitudinal data collected by IQVIA(R) on quarterly sales by wholesalers to retail pharmacies in Brazil from 1998 through 2010, grouped by originators, branded generics, and generic products in three therapeutic classes (antibiotics, antidiabetics, and antihypertensives). Outcomes included market share (proportion of the total private market volume), sales volume per capita, prices and number of manufacturers by group.

Results: In the private market share, generics became dominant in each therapeutic class but the speed of uptake varied. Originators consistently lost most market share while branded generics varied over time. By the end of the study period, generics were the most sold product type in all classes, followed by branded generics. The number of generic manufacturers increased in all classes, while branded generics increased just after the policy but then decreased slowly through the end of 2010. For approximately 50% of the antibiotics analyzed, branded generics and generics had lower prices than originators. For antidiabetics, branded generic and generic prices were quite similar during the period analyzed. Price trends for the various subclasses of antihypertensive exhibited very different patterns over time.

Conclusion: Sales of branded generics and originators decreased substantially in the three therapeutic classes analysed following the introduction of the generics policy in Brazil, but the time to market dominance of generics varied by class.