Update of the budget impact analysis of the simplification to atazanavir + ritonavir + lamivudine dual therapy of HIV-positive patients receiving atazanavir-based triple therapies in Italy starting from data of the Atlas-M trial

n 2017, the authors published an article to assess the financial consequences for the Italian National Health Service, over a 5-year period, of the adoption of a simplification strategy to atazanavir (ATV) + ritonavir (r) + lamivudine (3TC) dual therapy of HIV-positive patients receiving ATV plus two nucleoside reverse transcriptase inhibitors (NRTIs) starting from data of the Atlas-M trial at 48 weeks.1 Consequently to the publication of the clinical results of the Atlas-M trial at 96 weeks, we updated the model implemented for the analysis, considering the most recent evidence.2 The model was adapted considering the transitions among antiretroviral therapies (ARTs) observed in the trial, as reported in Figure 1, for years 1 and 2, and maintaining for years 3, 4, and 5 the same differential effectiveness (percentage of patients without virologic failure) observed between 48 and 96 weeks. In detail, the percentage of virologic failures considered in year 1 were 4.51% for ATV+r+2 NRTI and 0.76% for ATV+r+3TC; and in each following year were 8.66% for ATV+r+2 NRTI and 3.05% for ATV+r+3TC.