Effectiveness, Safety, and Tolerability of a Switch to Dual Therapy with Dolutegravir Plus Cobicistat-Boosted Darunavir in Treatment-Experienced Patients with Human Immunodeficiency Virus

Background: Dual regimen with dolutegravir plus cobicistat-boosted darunavir (DTG/DRV/c) is reasonable alternative option for patients with existing resistance and/or intolerance to nucleoside reverse transcriptase inhibitors (NRTIs).

Material and methods: All patients who switched to DTG/DRV/c among treatment-experienced patients with human immunodeficiency virus (HIV) in a tertiary university hospital were selected. We analyzed the effectiveness, safety, and tolerability based on serial laboratory data and clinical findings. The primary endpoint was defined as the proportion of patients with plasma HIV RNA below 50 copies/mL at week 48 after switch. Secondary endpoints included evaluation of safety and tolerability.

Results: Thirty-one patients were retrospectively analyzed. The main reasons for the change to DTG/DRV/c were treatment failure in 13 patients (41.9%), simplification in 12 patients (38.7%), and adverse drug reaction in 6 patients (19.4%). Among the 13 patients who switched owing to treatment failure, the proportion of patients in whom the viral loads were suppressed to less than 50 copies/mL increased from 0% at baseline to 45% at 4 weeks, 50% at 12 weeks, 50% at 24 weeks, and 66.7% at 48 weeks. HIV virus levels decreased and CD4⁺ T cell counts increased during the follow-up period. In non-treatment failure patients (18 patients), the levels of viral suppression and CD4⁺ T cells were maintained. There were no significant differences in renal function, liver function, glucose levels, and lipid profile before and after regimen changes. The tolerability was very good: 30 patients (96.8%) tolerated the drugs well and only 1 patient discontinued owing to no improvement in renal insufficiency. Two patients (6.4%) in treatment failure group failed to reach viral suppression.

Conclusion: The use of DTG/DRV/c in HIV treatment-experienced patients appears to be a very good regimen for switch therapy that is effective and well tolerated, without significant adverse drug reaction.