(196) The Effect of Generic Market Entry on HIV Treatment Cost in Portugal

Publication Number: 870

Background: HIV infection remains a public health concern, with approximately thirty-eight thousand people in treatment in Portugal. This results into increasingly high consumption levels of medicines for HIV, associated with high costs for the Portuguese healthcare service. Hospital management boards have tools that help control expenditure, and manage tight budgets; one of them is the use of generics. When branded medicines lose market exclusivity, generics typically enter the market at lower prices, decreasing the cost of treatment for patients.

Objectives: To determine the impact of generic entry on the HIV patient treatment cost between the period of 2011 to September 2021. Additional outcomes aimed at the characterization of the consumption and expenditure evolution of HIV pharmacological classes across a time period of nine years (2011-2020).

Methods: A quasi-experimental interrupted time-series analysis was conducted to examine the HIV treatment cost and expenditure, as well as the unit cost per HIV medicine, from data of 26 hospitals of the Portuguese healthcare service during January 2011 to September 2021. Data regarding medicine consumption and expenditure were acquired from INFARMED's database, while the number of patients was provided quarterly by the Information System for Contracting and Monitoring (SICA). Seven HIV generic medicines were analysed (Emtricitabine + tenofovir; Ritonavir; Lopinavir + Ritonavir; Darunavir; Lamivudine + Abacavir; Efavirenz and Tenofovir). All generics entered the hospital setting from 2012 and 2020 and were selected according to the hospital's consumption level. To find statistical significance of our data, we used regression models that control for baseline trends to estimate changes in the levels and trends of expenditure and average treatment cost after generic market entry.

Results: Our results showed that, for all generics selected, generic introduction decreased patient treatment cost and HIV expenditure between 26 to 35%, and 10 to 15%, respectively. In contrast, the unit cost of medicines didn’t change significantly before and after the entry of any generic. We also verified with the introduction of emtricitabine + tenofovir, abacavir + lamivudine, efavirenz and tenofovir a decrease in the trend before and after generic entry, but those results were not statistically significant. Additionally, we saw no significant level changes before and after generic entry.

Conclusions: Our analysis suggests that generic introduction led to a decrease in patient treatment cost and HIV expenditure. However, the potential economic benefit of generic entry could have been diluted by external factors, such as, an increased consumption of fixed-dose associations of three INNs with no generics available in the market.