Budget impact analysis of switch to darunavir/ritonavir monotherapy in Greece

Abstract

BackgroundIn virologically suppressed patients, simplifying to darunavir/ ritonavir (DRV/r) monotherapy maintains HIV RNA suppression and could lower treatment costs. Monotherapy is mentioned as an alternative treatment option in the Greek therapeutic guidelines (posted in the Greek Health Authority website), even though it is not included in the label of darunavir or any other PI.MethodsIn the MONET trial 256 patients with HIV RNA<50 copies/mL and no history of virological failure on HAART were switched to DRV/r 800/100 mg once daily, either as monotherapy (n=127) or with 2NRTI (n=129). The three‐year analysis of the MONET trial was used to calculate the overall nationwide cost of switching to DRV/r monotherapy in Greek patients. We used a ‘switch included’ analysis at Week 144 to account for additional antiretrovirals taken after initial treatment failure. Published Greek hospital prices of antiretrovirals were used in this analysis. Data from a local expert panel were used to estimate the number of patients currently receiving NNRTI versus PI‐based treatment in Greece, and the number of patients eligible for DRV/r monotherapy.ResultsIn the ITT switch included analysis, HIV RNA<50 copies/mL by Week 144 was 86.1% versus 84.3% in the DRV/r monotherapy and control arms. No patients developed resistance to DRV as measured by virtual phenotype. Before the trial, the mean annual cost of antiretrovirals was €5,625 for patients on NNRTI‐based HAART, and €6,935 for patients on PI‐based HAART. The mean per‐patient cost in the monotherapy arm was €4,514 in the MONET trial (including the cost of intensification with NRTIs where needed): this annual cost of antiretrovirals was €1,111 lower (20%) than NNRTI‐based treatment, and €2,421 (35%) lower than PI‐based treatment taken before the trial, respectively. According to the local expert panel feedback 5,230 people are treated with antiretrovirals in Greece (40% NNRTI‐based, 60% PI‐based) and 20% of patients (n=1,046) are eligible for PI monotherapy. Based on the MONET results, a switch to DRV/r monotherapy in 20% of patients could reduce the three‐year cost of antiretroviral treatment for these patients, from €20.11 million to €14.26 million.ConclusionsBased on the MONET trial results, if the 1,046 eligible patients were to switch to PI monotherapy the lower cost of DRV/r monotherapy versus triple therapy in Greece would allow a potential saving of up to €5.85 million over three years.