Sirtuin-2, NAD-Dependent Deacetylase, Is a New Potential Therapeutic Target for HIV-1 Infection and HIV-Related Neurological Dysfunction.

The implementation and access to combined antiretroviral treatment (cART) have dramatically improved the quality of life of people living with HIV (PLWH). However, some comorbidities, such as neurological disorders associated with HIV infection still represent a serious clinical challenge. Soluble factors in plasma that are associated with control of HIV replication and neurological dysfunction could serve as early biomarkers and as new therapeutic targets for this comorbidity. We used a customized antibody array for determination of blood plasma factors in 40 untreated PLWH with different levels of viremia and found sirtuin-2 (SIRT2), an NAD-dependent deacetylase, to be strongly associated with elevated viral loads and HIV provirus levels, as well as with markers of neurological damage (a-synuclein [SNCA], brain-derived neurotrophic factor [BDNF], microtubule-associated protein tau [MAPT], and neurofilament light protein [NFL]). Also, longitudinal analysis in HIV-infected individuals with immediate (n = 9) or delayed initiation (n = 10) of cART revealed that after 1 year on cART, SIRT2 plasma levels differed between both groups and correlated inversely with brain orbitofrontal cortex involution. Furthermore, targeting SIRT2 with specific small-molecule inhibitors in in vitro systems using J-LAT A2 and primary glial cells led to diminished HIV replication and virus reactivation from latency. Our data thus identify SIRT2 as a novel biomarker of uncontrolled HIV infection, with potential impact on neurological dysfunction and offers a new therapeutic target for HIV treatment and cure. IMPORTANCE Neurocognitive disorders are frequently reported in people living with HIV (PLWH) even with the introduction of combined antiretroviral treatment (cART). To identify biomarkers and potential therapeutic tools to target HIV infection in peripheral blood and in the central nervous system (CNS), plasma proteomics were applied in untreated chronic HIV-infected individuals with different levels of virus control. High plasma levels of sirtuin-2 (SIRT2), an NAD+ deacetylase, were detected in uncontrolled HIV infection and were strongly associated with plasma viral load and proviral levels. In parallel, SIRT2 levels in the peripheral blood and CNS were associated with markers of neurological damage and brain involution and were more pronounced in individuals who initiated cART later in infection. In vitro infection experiments using specific SIRT2 inhibitors suggest that specific targeting of SIRT2 could offer new therapeutic treatment options for HIV infections and their associated neurological dysfunction.

Antiretroviral treatment simplification with 3 NRTIs or 2 NRTIs plus nevirapine in HIV-1-infected patients treated with successful first-line HAART.

OBJECTIVES: To assess the virologic noninferiority of an antiretroviral treatment simplification with coformulated zidovudine/lamivudine/abacavir (group 1) vs. coformulated zidovudine/lamivudine plus nevirapine (group 2) in HIV-1-infected patients receiving successful first-line highly active antiretroviral therapy. METHODS: This is a prospective, multicenter, open-label, comparative, randomized, noninferiority study. A delta of 15% for differences in virologic suppression <200 copies/mL between groups was prespecified with a 1-sided 0.025 significance level. RESULTS: A total of 134 patients were included into this study: 68 were allocated to group 1 and 66 to group 2. By intention-to-treat analysis (switch equals failure), the percentage of virologic suppression <200 copies/mL (<50 copies/mL) at week 48 was 71.0% (65.1%) and 73.0% (63.3%) in groups 1 and 2, respectively (estimate for differences [<200 copies/mL]: -2.1, 95% CI: -17.4-13.1, P=0.783). Thirteen and 14 patients in groups 1 and 2, respectively, discontinued therapy due to adverse events. Dyslipidemia improved in both groups, with a higher improvement in low-density lipoprotein cholesterol (P=0.049) in group 1. CONCLUSIONS: Group 1 is not inferior to group 2 regarding virologic suppression <200 copies/mL. Both strategies improve lipid profile.

Safety and efficacy of once-daily didanosine, tenofovir and nevirapine as a simplification antiretroviral approach.

OBJECTIVE: To assess the efficacy and safety of a once-daily antiretroviral regimen in HAART-experienced subjects with long-lasting viral suppression. METHODS: One-hundred-and-sixty-nine patients with chronically suppressed viral load (limit of detection <50 copies/ml) were recruited. Based on patient willingness to simplify treatment, 84 of them continued receiving their usual treatment (BID Group) and 85 switched to once-daily didanosine/tenofovir/nevirapine (QD Group) in a non-randomized fashion. RESULTS: At week 48, the proportion of patients with viral suppression in the QD and in the BID Group, respectively, was 97 vs 100% in the per-protocol analysis (P = 0.497), and 76 vs 86% for the intention-to-treat analysis (P = 0.176). Nevertheless, CD4 count decreased in the QD Group, with a mean decline of 95 cells/mm3 (95% CI: 45-145). Twelve subjects in the QD Group (14%) discontinued treatment due to adverse events, mainly nevirapine-related hepatitis (6%). No significant differences regarding the rate of acute pancreatitis or peripheral neuropathy were observed between both groups. A significant improvement in the lipid profile was only seen in the QD Group. High levels of adherence were observed in both groups during follow-up, as well as a good quality of life. At week 48, a reduction in effort to take medication (P < or = 0.001) and an increment in the satisfaction with the treatment (P < 0.001) was only seen in the QD group. No differences were observed in median nevirapine trough levels between patients on twice-daily nevirapine at baseline (4820 ng/ml) and subjects in the QD Group (6090 ng/ml, P = 0.30). CONCLUSION: Treatment simplification to a once-daily antiretroviral regimen based on didanosine, tenofovir and nevirapine may be a valid approach in HIV-infected subjects with long-lasting viral suppression. Combination of standard doses of didanosine and tenofovir may have contributed to the CD4 cell decline observed with this QD regimen.