Stable HIV-1 reservoirs on dolutegravir maintenance monotherapy: the MONODO study

Objectives: Dolutegravir (DTG) is a highly effective integrase inhibitor with a strong genetic resistance barrier and a potential role in simplified HIV maintenance treatment. We assessed the feasibility of DTG maintenance monotherapy and measured HIV reservoirs on DTG monotherapy.

Methods: An interventional, open-label, single-arm study including eight virologically suppressed HIV-1-infected patients switched to DTG 50 mg once daily for 24 weeks was performed. HIV-1 RNA levels in plasma and cerebrospinal and seminal fluids were measured at baseline and week 24, as well as HIV-1 DNA in peripheral cells and DTG concentrations in these compartments.

Results: HIV-1 RNA remained undetectable in all samples of blood, cerebrospinal fluid and sperm throughout the 24 weeks, except for one cerebrospinal fluid sample with a value of 28 HIV-1 RNA copies/mL at week 24. One patient discontinued the study because of a neurological side effect. There was no change in the mean HIV-1 DNA level between baseline and week 24. Plasma and cerebrospinal fluid DTG concentrations reached therapeutic levels in all patients in these two compartments.

Conclusions: In this small sample of carefully selected patients, HIV-1 reservoirs were well controlled on DTG monotherapy over a period of 24 weeks. Viral suppression was also maintained throughout follow-up.