Trends in uptake of recently approved antiretrovirals within a national healthcare system

Abstract

The aim of the study was to describe Veterans Healthcare Administration (VHA) system-wide uptake of three HIV protease inhibitors: atazanavir, darunavir and tipranavir. This retrospective cohort study evaluated VHA uptake of three target antiretrovirals and lopinavir/ritonavir in each complete 90-day quarter since approval to December 2007 using VHA HIV Clinical Case Registry data. We assessed uptake using number of new prescriptions, number of providers and facilities prescribing target agents, provider type, clinic type, facility size and location within four US regions. Overall, 6551 HIV-infected veterans received target antiretrovirals. Uptake was generally greatest within the first year after Food and Drug Administration (FDA) approval, and then slightly declined and plateaued. Geographically, early adoption of new antiretroviral drugs tended to occur in the Western USA, as evidenced by comparison of uptake patterns of new antiretrovirals to use of all antiretroviral agents. A small percentage of prescribers of all antiretrovirals were responsible for new prescriptions for target medications, particularly for darunavir and tipranavir. Providers at almost 50% of VHA facilities were prescribing these agents within the first year. Uptake of new antiretrovirals in the VHA generally reflected overall prescribing of all antiretrovirals, suggesting a lack of VHA impediments to new antiretrovirals in the healthcare system. Some regional variation in uptake among the targeted antiretrovirals occurred over time but tended to resolve after the first several months. Providers responsible for early prescribing of the target medications were limited to a fraction of providers who tended to be physicians who practised in infectious disease (ID) clinics at medium-sized facilities.