One Year Follow-Up of Darunavir/Cobicistat Monotherapy in Pretreated HIV Patients

Abstract

Introduction: Boosted protease inhibitor monotherapy (PI/r ) : Darunavir/ritonavir (DRV/r) or Lopinavir/ritonavir (LPV/r) monotherapy is only provided in the major treatment guidelines in pre-treated HIV patients to prevent toxicity associated with nucleoside/nucleotide reverse transcriptase inhibitor (NRTIs), reduce costs and simplify antiretroviral treatment. To start PI/r monotherapy, according to GESIDA g uidelines 2016, patients need to meet the following criteria: absence of chronic hepatitis B, plasma viral load <50 copies/ mL for at least 6 months and absence protease inhibitors mutations or previous virologic failures to PI/r. Currently, there are no studies that evaluate the efficacy and safety of DRV/COBI monotherapy. Methods: This prospective study analyzed pretreated HIV patients with DRV/r monotherapy that were switched to DRV/COBI monotherapy. The aim of the study is to describe the effectiveness and safety of the DRV/COBI monotherapy. Results: A total of 78 patients were evaluated. In total 11.53% (9/78) patients developed blips (Plasma viral load: 50-200 copies/ml) in our study and four patients had a viral load ≥ 200 copies/mL. Twelve patients (15.38%) switched to another antiretroviral treatment, so at week 48 only 66 of the 78 patients continued with DRV/COBI monotherapy. Three patients continued with blips at week 48. Despite blips, virological rebounds and switch in treatments, 95.45% (63/66) of the patients with DRV/COBI monotherapy were maintained with a viral load <37 copies/mL at week 48 of the follow-up. In addition, there had been a slight increase in the CD4+ T cell count at week 48 of follow up. As for safety, there were no significant differences in lipid profile, liver function (transaminases) and renal function between DRV/r and DRV/COBI monotherapy. Conclusions: DRV/COBI monotherapy seems to be effective and safe (lipid profile, liver and kidney function). However, it will be necessary to design specific studies comparing DRV/r vs DRV/COBI monotherapy to confirm these results.