CROI 2019 Abstract eBook

Abstract eBook

Poster Abstracts

475 WHICH PRECLINICAL SPECIES MIMICS TISSUE PENETRATION OF ARV DRUGS IN HUMANS? Jason R. Pirone 1 , Ramesh K. Akkina 2 , J. V. Garcia-Martinez 1 , Paul Luciw 3 , Lourdes Adamson 3 , Craig Sykes 1 , Nicole White 1 , Amanda Schauer 1 , Kimberly H. Blake 1 , Erin M. Burgunder 1 , Aaron S. Devanathan 1 , Nithya Srinivas 1 , Elias Rosen 1 , Angela Kashuba 1 1 University of North Carolina at Chapel Hill, Chapel Hill, NC, USA, 2 Colorado State University, Fort Collins, CO, USA, 3 University of California Davis, Davis, CA, USA Background: For HIV cure strategies like “kick and kill” to succeed, antiretroviral (ARV) drugs must reach protective concentrations in putative viral reservoirs, including lymphoid tissue and sequestered sites like the brain and genital tract. Extrapolating outcomes of animal studies to humans requires understanding the specifics of ARV tissue distribution. Here, we characterize penetration of 6 ARVs in 2 humanized mouse models, nonhuman primates (NHPs), and HIV+ humans. Methods: ARVs/doses were selected based on published strategies for animals and humans (Thompson, AIDS, 2017). 12 BLT humanized mice and 36 RAG-hu mice (female) were used. 17 macaques (5 female, 12 male) and 19 human subjects (3 women/16 men) were used. Animals were dosed for 10 days before necropsy. Human samples were obtained from the National NeuroAIDS Tissue Consortium harvested 8-47h post dose. These drugs were investigated: tenofovir (TFV), emtricitabine (FTC), raltegravir (RAL), maraviroc (MVC), efavirenz (EFV) and atazanavir (ATZ). 8 tissue types were snap frozen and stored at -80°C. ARV concentrations were assayed by LC-MS/MS (LLOQ: 0.002-0.01 ng/ mL). A Bayesian measurement-error model was used to characterize plasma and tissue concentration relationships. Results: Across species, variability in ARV concentrations was similar among plasma (CV 0.4-3.2) and tissues (CV 0.3 - 3.3). For a given plasma concentration, tissue concentrations were most similar among NHPs and humans. With few exceptions, tissue exposure from highest to lowest were: human > NHP > BLT > RAG-hu (Figure). For RAL and FTC, under most conditions, the relationship between plasma and tissue concentration was flat (95% highest density interval (HDI) includes 0). Across all tissues/species, only EFV and TFV concentrations were proportional to plasma. Largest slopes (log-log scale) were seen for EFV and TFV in NHP spleen with median values and lower and upper bounds of the 95% HDI of 0.95 (0.71,1.17) and 0.78 (0.50, 1.06) respectively. Conclusion: NHP dosing strategies result in similar tissue concentrations to humans. For RAL and FTC, it is unlikely that increasing doses will increase tissue penetration substantially. For TFV and EFV, it may be possible to increase tissue penetration by adjusting doses. Changing tissue concentrations for other ARVs is dependent on drug/tissue type. These results add to current data on tissue penetration of ARVs and have implications on interpreting HIV treatment, prevention, or cure interventions between models.

1 University of Turin, Turin, Italy, 2 Amedeo di Savoia Hospital, Torino, Italy, 3 Maria Vittoria Hospital, Torino, Italy Background: Antiretrovirals (ARVs) long-term efficacy and HIV-functional cure require the abolition of viral replication in every body compartment as well as the effect of the immune system. The olfactory mucosa (OM) is a unique tissue at the intersection of the central nervous (CNS) and lymphatic system; preliminary data suggest that HIV may persist in the OM despite antiretroviral treatment. Methods: Patients with neurocognitive disorders were included in a diagnostic study and OM samples were obtained through nasal brushing. The analysis of ARVs concentrations in swabs was performed as follows on frozen swabs. They were weighted upon extraction and then inserted in PTFE tubes along with 40µl of internal standard (marked with stable isotopes) working solution plus 500 µl of water:methanol solution (30:70 v:v). These tubes were then vortex-mixed 10 sec and sonicated for 10 minutes at 40°C. The dry extracts were dissolved in 110 µL of water:acetonitrile:acetic acid (94.9:5:0.1 v:v:v) solution and 10 µl of acid phosphatase (0.5 X) and incubated for 1 hour at 37°C, in order to convert phosphate metabolites of NRTIs to the free form. The resulting extracts were analyzed by using HPLC/MS-MS, obtaining absolute amounts (ng): these results were then normalized for the estimated weight of the extracted material (the difference between the initial weight and after the extraction process). The lower limit of quantification was 0.3 ng per sample, corresponding to a mean concentration of 3 pg/mg of OM swab. Results: 31 patients were included. They were mostly male (80.6%) and of European ancestry (96.8%); median age and BMI were 51 years (46-58) and 23.5 Kg/m2 (19.7-27.7). Median current and nadir CD4+ T-cells were 649/uL (360-965) and 185/uL (88-278); after a median o 33 months (8-123) months of virological suppression plasma, CSF and OM HIV RNA were below 20 copies/ mL in 27 (87.1%), 22 (71%) and 29 (93.5%) participants. OM concentrations as well as OM to plasma and OM to CSF ratios are shown in Table 1: a marginal correlation between OM and plasma (rho=0.30, p=0.007) and CSF concentrations (rho=-0.22, p=0.072) was observed. Conclusion: We developed a novel method for quantifying ARVs in mucosal tissues obtained through brushing swabs. In this small pilot study antiretroviral concentrations in the OM were highly variable with protease inhibitors showing the highest exposure. Further studies are needed to compare ARVs’ penetration and residual viral replication.

Poster Abstracts

477 INFLUENCE OF TENOFOVIR-MONOESTER AND TENOFOVIR ON INTRACELLULAR TENOFOVIR-DIPHOSPHATE

Kristina M. Brooks 1 , Mustafa E. Ibrahim 1 , Jose R. Castillo-Mancilla 1 , Samantha MaWhinney 2 , Cricket McHugh 1 , Lane R. Bushman 1 , Jennifer J. Kiser 1 , Sybil Hosek 3 , Gregory D. Huhn 3 , Peter L. Anderson 1 1 University of Colorado Anschutz Medical Campus, Aurora, CO, USA, 2 Colorado School of Public Health, Aurora, CO, USA, 3 Stroger Hospital of Cook County, Chicago, IL, USA Background: Tenofovir (TFV)-monoester (TFV-mE) is the intermediate moiety formed during the hydrolysis of TFV disoproxil fumarate (TDF) to TFV. TFV-mE is more lipophilic than TFV, and thus may influence intracellular TFV-diphosphate

476 ANTIRETROVIRALS CONCENTRATIONS IN THE OLFACTORY MUCOSA OF HIV-POSITIVE PATIENTS Andrea Calcagno 1 , Amedeo De Nicolò 1 , Mattia Trunfio 1 , Tiziano Allice 2 , Daniele Imperiale 3 , Claudia Bartoli 3 , Valeria Ghisetti 3 , Maria Enrica Amasio 3 , Antonio D’Avolio 1 , Giovanni Di Perri 1 , Stefano Bonora 1

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