Durability of lopinavir/r monotherapy in people with viral load ≤50 copies/Ml

There is debate about whether lopinavir/r mono‐therapy (LPV/r‐MT) is a valid treatment option for HIV‐infected patients who have shown perfect adherence to therapy. The objective was to evaluate the durability of LPV/r‐MT in terms of time to virological rebound (VR), time to discontinuation/intensification or a composite endpoint considering both (=treatment failure). We also identified factors associated with faster progression to treatment failure and estimated the median CD4 count over time while people were still on LPV/r‐MT. Patients enrolled in 10 clinical sites in Italy who ever started LPV/r‐MT with a viral load ≤50 copies/mL (baseline) are included. Patients’ follow‐up accrued from baseline to the date of the event of interest (VR, defined using the thresholds of 50 and 200 copies/mL, or discontinuation/intensification) or at the date of last available visit/VL measurement. Standard survival analysis employing Kaplan‐Meier curves was used. We studied 139 patients starting LPV/r‐MT on average in 2010 (IQR: 2009–2011) with a VL≤50 copies/mL already for a median of 1 month (range: 1–17). Median age 45 years (IQR: 39–50), 35% females, 32% IDU. Median time from first initiation of ART was 33 months (16–58) with no history of virological failure. Median (IQR) marker values at baseline were 611 (432–741) CD4 count cells/mm 3 , 937 (655–1254) CD8 count and 28 (19–47) IU/L of ALT. Median CD4 count were 519 cells/mm 3 at 3 months, 660 at 6 months, 603 at 9 months and 467 at 12 months. The table shows the Kaplan‐Meier estimates by 1 year and 2 years for a number of endpoints examined. There was a wide range of estimates depending on the endpoint used. Of those stopping/intensifying, 6 people (4%) added Truvada (n=4), Kivexa (n=1) and darunavir (n=1), the remaining 8 restarted cART.1 year 2 years End point No. events Point estimate 95% CI Point estimate 95% CIStop/ intensification 14 4.6% 0.7–8.5 14.0% 6.2–21.8Single VL>50 32 19.3% 11.1–26.8 29.7% 19.2–38.8Confirmed VL>50 8 5.7% 1.8–9.6 7.4% 1.5–13.3Single VL>200 10 7.5% 1.6–13.4 11.1% 3.2–18.8Single VL>200 or stop / intensification 18 10.5% 4.6–16.4 19.1% 9.2–28.8In our ‘real‐life’ setting, by 2 years of starting LPV/r‐MT, 70% of patients remained persistently suppressed ≤50 copies/mL. This percentage was >80% when considering only confirmed virological failures while people still remaining on the drug. Our results, though lacking precision because of the small number of events, are consistent with those of recent clinical trials.