Budget impact analysis of efavirenz daily dose reduction at the Verona University Hospital

Efavirenz is a non-nucleoside-reverse-transcriptase-inhibitor used as part of highly-active-antiretroviral-therapy for the treatment of the human immunodeficiency virus (HIV) type 1 infection. The present paper aims to describing the impact of efavirenz dose reduction on the pharmaceutical budget at the Verona University Hospital. A budget impact analysis comparing two prescribing scenarios was conducted: all patients treated with the efavirenz full dose (600 mg per day) vs. a proportion of patients treated with a reduced dose (200-400 mg per day). All outpatients referring to the Infectious Disease Clinic in the period November 2009-October 2011 were selected. Out of 132 patients treated with efavirenz, 25 were not considered, mainly due to a too short treatment period. Of the remaining 107 patients, 68 received the full dose, while 39 received a reduced dosage. The analysis included the cost of the drug and of diagnostic tests, from the National Health Service perspective. The daily dose reduction of efavirenz saved 54,664 euros (a 30% expenditure reduction). In sum, new strategies for pharmaceutical system sustainability are necessary; despite forthcoming expiring patents of several drugs, spending on antiretroviral drugs is expected to rise. This paper suggests a way of linking clinical benefits and cost reduction.