The effect of switching protease inhibitors to raltegravir on endothelial function, in HIV-infected patients

Lipid management is one of the cornerstones of cardiovascular risk reduction. Treatment of HIV infection with protease inhibitors (PIs) may cause dyslipidaemia, whilst the integrase inhibitor raltegravir (RAL) has a relatively favorable effect on plasma lipids. We examined the effect of switching from PIs to RAL on endothelial function, and its effect on immunological and inflammatory parameters.

We performed a 16-week open-label prospective crossover study: 8 weeks intervention (switch PIs to RAL) and 8 weeks control (unchanged cART regimen). Flow-mediated dilatation (FMD), inflammatory plasma, and cellular markers of immune activation were measured at weeks 0, 8, and 16.

Study participants (n = 22) with a median age of 50 years (IQR 42–60) and known HIV infection of 6.5 years (IQR 5.0–17.3) were on stable cART with undetectable HIV viral loads. After 8 weeks of RAL therapy, a reduction in FMD of −0.81% was seen, compared to +0.54% control (pairwise, p = 0.051), while fasting total cholesterol (−17% versus +10%; p < 0.001), LDL cholesterol (−21% versus −3%; p = 0.026), and triglycerides (−41% versus +18%; p = 0.001) significantly decreased during RAL therapy compared to the control.

Furthermore, a relation between the change in percentage of B-1 cells and the change in FMD was found (β 0.40, 95%CI 0.16; 0.64, p = 0.005) during treatment with RAL. Finally, during RAL therapy, 27% of the patients experienced an increased ALT rise.

We present an overall negative study, where switching from PIs to RAL slightly reduced the endothelial function while decreasing plasma lipids, thus possibly decreasing the CVD risk in the long term. A transient elevation of ALT was seen upon switch to RAL.