The antiretroviral nevirapine (NVP) is associated to a reduction of atherosclerotic lesions and increases in high-density lipoprotein (HDL)-cholesterol. Despite being a hepatotoxic drug, which forbids its re-purposing to other therapeutic areas, not all NVP metabolites have the same potential to induce toxicity. Our aim was to investigate the effects of NVP and its metabolites in an exploratory study, towards the identification of a candidate to boost HDL. A pilot prospective (n = 11) and a cross-sectional (n = 332) clinical study were performed with the following endpoints: HDL-cholesterol and apolipoprotein A1 (ApoA1) levels, anti-HDL and anti-ApoA1 antibodies titers, paraoxonase, arylesterase and lactonase activities of paraoxonase-1, and NVP's metabolite profile. NVP treatment increased HDL-cholesterol, ApoA1 and paraoxonase-1 activities, and lowered anti-HDL and anti-ApoA1 titers. In the prospective study, the temporal modulation induced by NVP was different for each HDL-related endpoint. The first observation was a decrease in the anti-HDL antibodies titers. In the cross-sectional study, the lower titers of anti-HDL antibodies were associated to the proportion of 2-hydroxy-NVP (p = 0.03). In vitro models of hepatocytes were employed to clarify the individual contribution of NVP's metabolites for ApoA1 modulation. Long-term incubations of NVP and 2-hydroxy-NVP in the metabolically competent 3D model caused an increase in ApoA1 reaching 43 % (p < 0.05) and 86 % (p < 0.001), respectively. These results support the contribution of drug biotransformation for NVP-induced HDL modulation, highlighting the role of 2-hydroxy-NVP as ApoA1 booster and its association to lower anti-HDL titers. This biotransformation-guided approach allowed us to identify a non-toxic NVP metabolite as a candidate for targeting HDL.The research work was funded by Fundação para a Ciência e a Tecnologia (FCT) Portugal [grant references: SFRH/BD/92191/2013, PhD
grant to ATM; CEECIND/02001/2017 grant to AMA; EXPL/DTP-FTO/0204/2012; RECI/QEQ-MED/0330/2012; UID/QUI/00100/2019; PTDC/MED-TOX/29183/2017; UID/DTP/04138/2019; UID/QUI/
00100/2013; iNOVA4Health - UID/Multi/04462/2013, a program
financially supported by FCT/Ministério da Educação e Ciência, through national funds and co-funded by FEDER under the PT2020 Partnership Agreement].info:eu-repo/semantics/publishedVersio
