CROI 2024 Abstract eBook

Abstract eBook

Poster Abstracts

881

One-Dose Efficacy of Long-Acting Injectable Diarylquinoline in Mouse Model of TB Preventive Therapy James J. Hobson 1 , Si Yang Li 2 , Nicole C. Ammerman 2 , Jonathan Massam 1 , Joanne Sharp 1 , Nader Fotouhi 3 , Steve Rannard 1 , Andrew Owen 1 , Eric Nuermberger 2 1 University of Liverpool, Liverpool, United Kingdom, 2 The Johns Hopkins University, Baltimore, MD, USA, 3 Global Alliance for TB Drug Development, New York, NY, USA Background: Use of long-acting injectables (LAIs) has the potential to simplify tuberculosis (TB) preventive therapy (TPT) addressing issues such as pill burden and adherence. Bedaquiline (BDQ) is a key drug in new short-course regimens for treatment of rifampin-resistant TB and could provide a short-course "pan"-TPT option for drug-susceptible and rifampin-resistant infections. BDQ and other diarylquinolines (DARQ) have physicochemical and pharmacokinetic (PK) properties amenable to LAI formulation. The aim of this work was to preclinically characterize a new more potent DARQ as a single phase spray dried nanosuspension LAI formulations for use in TPT. Methods: Single intramuscular dose PK profiles for 3 DARQ LAI formulations (formulations A-C) were characterized in mice. Based on mouse PK, formulation B was tested for bactericidal activity in a validated BALB/c mouse model of TPT at single intramuscular (IM) doses of 62.5, 125 and 250 mg/kg, with the goal of maintaining a ≥36 ng/mL plasma target for 4-8 weeks. Formulations A and C were tested only at 125 mg/kg. Negative controls were untreated. Positive controls received daily (5 days/week) oral isoniazid-rifapentine (1HP), oral BDQ or oral DARQ for 4 weeks. Lung bacterial colony-forming units (CFU) counts and plasma DARQ exposures were measured 4-12 weeks after the start of treatment. Group mean CFU counts were analyzed using 1-way ANOVA and plasma exposure with non-compartmental PK analysis. Results: All DARQ LAI regimens had bactericidal activity over the first 4 weeks of treatment that was superior to 1HP (p<0.0001) and oral BDQ (p<0.0001 except p=0.05 for 62.5 mg/kg) and similar in magnitude to the same total DARQ dose given orally over 4weeks (Fig). Activity was dose-dependent for formulation B and similar for the 3 formulations at 125 mg/kg. Median DARQ C max was <1 µg/ml. Median AUC0-4w values were 137, 186 and 349 µg-h/ml and plasma concentrations were ≥36 ng/ml for 4, 6 and >6 weeks after the 62.5, 125 and 250 mg/kg doses of formulation B, respectively. Lung CFU and PK data at 8 and 12 weeks post-dose are pending. Conclusion: These data provide proof-of-concept for a highly efficacious pan-TPT regimen comprised of a single IM dose of an LAI DARQ formulation. Further preclinical development including studies to define the PK target, human dose estimates and GLP toxicology evaluation is highly warranted. Single Cell Transcriptomics Reveals Depletion of TB-Specific Th1 and Th17 Cells After HIV Infection Rachel A Pearson 1 , Krista N. Krish 1 , Wendy Whatney 1 , Walter Jaoko 2 , Kishor Mandaliya 3 , Julie Overbaugh 4 , Susan M. Graham 5 , R. Scott McClelland 5 , Sakeenah Hicks 1 , Jeffrey Maurer 1 , Christopher D. Scharer 1 , Cheryl L. Day 1 1 Emory University, Atlanta, GA, USA, 2 University of Nairobi, Nairobi, Kenya, 3 PathCare, Mombasa, Kenya, 4 Fred Hutchinson Cancer Center, Seattle, WA, USA, 5 University of Washington, Seattle, WA, USA Background: HIV substantially increases the risk of progression of Mycobacterium tuberculosis (Mtb) infection to active tuberculosis (TB) disease. This heightened risk of developing TB persists even in people with suppressed viral loads on long-term antiretroviral therapy (ART). The mechanisms underlying the loss of immune control of Mtb in people with HIV (PWH) remains unclear. We hypothesized that HIV dysregulates Mtb-specific CD4 T cells and that initiation of ART early following HIV infection will better preserve their functional capacity. Methods: PBMCs were collected from a longitudinal cohort of women who engage in sex work in Mombasa, Kenya. PBMCs were evaluated from women within one year before and after HIV acquisition (n=5), and from women with HIV before and after ART initiation (n=8). PBMCs were incubated overnight with Mtb whole-cell lysate, followed by FACS sorting to purify CD40L+CD69+

Mtb-specific CD4 T cells for single-cell RNA-sequencing (scRNA-seq) using the 10X Genomics platform. Results: Unsupervised clustering of scRNA-seq data revealed that distinct populations of Mtb-specific Th1 and Th17 cells are depleted after HIV infection. Differential gene expression analysis indicated decreased expression of genes encoding multiple effector molecules, including IFNG , IL22 , TNF , IL17F , GZMB , GZMA , and GNLY , in Mtb-specific CD4 T cells in the first year after HIV infection, compared with Mtb-specific CD4 T cells from the same individuals before HIV infection. Moreover, PWH who initiated ART within 6 months of HIV infection exhibited increased proportions of Th1 and Th17 cells following ART compared with before ART, whereas recovery of Mtb-specific Th1 and Th17 cells was not observed in PWH who initiated ART >1 year after HIV acquisition. Additionally, multiple cytokine genes, including IFNG , IL2 , IL22 , and TNF , were downregulated in Mtb-specific CD4 T cells from PWH who started ART later (>1 year), compared with those who initiated ART earlier (<6 months) after HIV acquisition. Conclusion: These novel single-cell transcriptomic studies indicate that HIV acquisition is associated with dysregulation of the Mtb-specific CD4 T cell transcriptome and depletion of crucial Th1 and Th17 cell populations within the first year after HIV infection, which may contribute to compromised Mtb control in PWH. Moreover, these results suggest that ART initiation within 6 months of HIV acquisition may be beneficial in preserving Mtb-specific Th1 and Th17 cells in PWH. Monocyte Activation in Persons With HIV and Latent TB Co-Infection in the ACTG A5279/BRIEF TB Trial Moises A Huaman 1 , Manuel G. Feria Garzon 1 , Ashley McKhann 2 , Xinyu Du 2 , Khuanchai Supparatpinyo 3 , Claire A. Chougnet 4 , Michelle A. Kendall 2 , Frederick K. Sawe 5 , Kristine M. Erlandson 6 , Netanya S. Utay 7 , Michael M. Lederman 8 , Susan Swindells 9 , Amita Gupta 10 , Richard E. Chaisson 10 , Carl J. Fichtenbaum 1 1 University of Cincinnati, Cincinnati, OH, USA, 2 Harvard TH Chan School of Public Health, Boston, MA, USA, 3 Chiang Mai University, Chiang Mai, Thailand, 4 Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA, 5 Kenya Medical Research Institute, Kilifi, Kenya, 6 University of Colorado, Aurora, CO, USA, 7 University of Texas Southwestern, Dallas, TX, USA, 8 Case Western Reserve University, Cleveland, OH, USA, 9 University of Nebraska Medical Center, Omaha, NE, USA, 10 The Johns Hopkins University, Baltimore, MD, USA Background: Latent Tuberculosis infection (LTBI) has been linked to increased immune activation and cardiovascular risk. We investigated the activation profile of monocytes from persons with HIV (PWH) who participated in the ACTG A5279 trial, a phase III trial of 4 weeks of daily rifapentine (RFP)/isoniazid (INH) versus 9 months of daily INH as TB prevention therapy (TPT). Methods: We analyzed available cryopreserved PBMCs obtained at baseline (pre-TPT) and at week 48 (post-TPT) from A5279 participants on antiretroviral therapy, with HIV viral load ≤200 copies/mL, and a tuberculin skin test (TST) or interferon-γ release assay (IGRA) result at entry. Unstimulated, thawed PBMCs were stained with markers of monocyte subsets (CD14, CD16), activation (HLA-DR, CD64, CD80, CD86), chemotaxis (CX3CR1, CCR2), and lipid uptake (CD36, CD163). In vitro stimulation with lipopolysaccharide (LPS) was performed to evaluate monocyte markers, and IL-6 and TNF-α expression. Samples were examined with multiparameter flow cytometry. Primary comparisons were between TST/IGRA-positive (evidence of LTBI) and TST/IGRA-negative groups. Linear regression of log 10 -transformed markers adjusted comparisons for age, sex at birth, country, and CD4 count. Results: 58 participants from 4 countries were included. Median age was 38 years (IQR, 34 – 47). 33 (57%) men and 25 (43%) women. At baseline, compared to TST/IGRA-negative participants (n=27), those with LTBI (n=31) exhibited higher percentage and/or median fluorescence intensity (MFI) of CD64 and CCR2 on their total and classical monocytes. At week 48, compared to TST/ IGRA-negative group, participants with LTBI had higher percentage and/or MFI of CD64 on total and all monocyte subsets, as well as differential expression of CD80, CD163, and CX3CR1 across some monocyte subsets. Upon LPS stimulation, there were no differences in IL-6 or TNF-α production by TST/IGRA status; however, LTBI was associated with higher MFI of CD36 and CCR2, and lower MFI of CX3CR1 on total monocytes and subsets. In adjusted analyses, LTBI was consistently associated with increased MFI of CD64 (unstimulated) and CCR2 (post-LPS) at baseline and week 48 across monocyte subsets (Table). Conclusion: Compared to PWH with negative TST/IGRA, PWH with evidence of LTBI exhibited monocyte alterations indicative of persistent activation and tissue migration at baseline and week 48. Longitudinal changes will be evaluated in future studies.

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Poster Abstracts

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CROI 2024 274