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Naninck, T.

Publications and source records attributed to Naninck, T..

6 recordsLinked to original sources

A novel workflow integrating whole-body PET microdosing data and therapeutic-dose pharmacokinetics across species to inform first-in-human dose selection

Introduction: First-in-human studies require dose extrapolation from pharmacokinetic animal studies combined with safety assessments. Subtherapeutic doses of radiolabelled drugs can be administered in preclinical and early clinical development to gain a dynamic pharmacokinetic understanding, potentially informing pharmacologically-based pharmacokinetics (PBPK) models through whole-body PET data. Aims: to develop a PET-informed modelling framework for preclinical-to-human extrapolation, with dolutegravir as a case-study. Methods: We developed a structured workflow integrating micro- and conventional-dose data for interspecies and dose extrapolation. We built a whole-body PBPK model in PK-Sim/MoBi (v12.1) using non-human primate (NHP) data in 5 key organs incorporating dolutegravir physico-chemical properties, protein binding, metabolism and efflux. Sensitivity analyses and parameter estimation were performed sequentially first with PET microdosing organ data over 3h, then with fluid and tissue concentrations following a 2.5 mg/kg IV injection. Finally, 100 Caucasian healthy adults (50% male, 20-80 years) receiving 50 mg qd po after high-fat meals were simulated using the two sets of estimated parameters and physiology-related parameter distributions provided by PK-Sim. Results: Dolutegravir blood data were well described in NHPs over 3 hours, with parameters adjusted to handle the macrodose-related changes. While microdose-based parameter estimates systematically underpredicted exposure, combining NHP micro- and conventional dose data predicted steady-state geometric mean AUC0-24 and Cmax closely matching human reported profiles, although slightly underpredicting Ctrough. Conclusions: PET-PBPK modelling combining micro- and conventional doses in NHPs successfully predicted dolutegravir concentrations in healthy volunteers, additionally informing tissue distribution. This proof of concept study supports early PET data acquisition to build robust priors for first-in-human studies.

pharmacology and toxicology↗

Disease progression is associated with differential neutrophil maturation in Mycobacterium tuberculosis-infected macaques

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is associated with clinical diversity and outcomes ranging from latent TB to active TB with distinct pathophysiologies. However, our understanding of the innate immune mechanisms related to the protection or progression of TB is limited. Among innate immune cells, the role of neutrophils is not fully elucidated, as they have been shown to exhibit both protective and harmful capacities in TB. This duality suggests possible differences in the nature and type of neutrophils present during the infection, generating different effects. We hypothesized that Mtb infection induces changes in neutrophil phenotype and function, influencing the infection outcomes. In order to decipher the link between neutrophils and disease progression, we used a cynomolgus macaque model of human TB. Based on clinical, bacteriological, and positron emission tomography with X-ray computed tomography (PET/CT) scan parameters, animals were stratified into two categories: animals that rapidly progressed to an active form of TB, designated as "fast progressors", and "slow progressors", which include low symptomatic or asymptomatic animals. In this study, we identified transcriptomic signatures of type I interferons and neutrophil degranulation in macaques with fast progression to active TB, which were not observed in animals with slow TB progression. Unsuppervised mass cytometry analysis showed the emergence of blood immature neutrophils (CD101+ CD10-) in fast progressing animals. In addition, circulating neutrophils from infected animals displayed capacities to modulate TNF- production and cytotoxic function of CD8 T cells in a contact-dependent mechanism. In the lungs, neutrophils infiltration in granuloma was higher in fast progressors and specifically located in the lymphocyte-rich region in lesions. These data suggest that specific neutrophil subpopulations are associated with disease progression. Furthermore, these data suggest that neutrophils may modulate CD8 T cells functions, which in turn contribute to the loss of Mtb control and fuel inflammation. AUTHORS SUMMARYMycobacterium tuberculosis (Mtb) infection in humans is associated with a wide range of disease progression, ranging from latent tuberculosis (TB) to active TB. Understanding immune factors leading to the control of the infection or disease progression is essential to identify new biomarkers and targets for host-directed therapies. Innate immunity plays an important role in inflammatory imbalance observed in active TB, among which neutrophils have both beneficial and detrimental roles. Using a macaque model developing a broad range of clinical forms of TB, we seek to understand the links between neutrophils and disease progression. We found that rapid progression to active TB leads to type I interferon signalling and neutrophil activation. In the blood, immature neutrophils were enriched when the disease progressed. In case of severe TB, Neutrophils also infiltrate a specific region of lung TB lesions rich in T lymphocytes, whereas they could modulate CD8 T cells. Our study provides new insights into the role of neutrophils in TB progression.

immunology↗

A novel adjuvant formulation induces robust Th1/Th17 memory and mucosal recall responses in Non-Human Primates

After clean drinking water, vaccination is the most impactful global health intervention. However, development of new vaccines against difficult-to-target diseases is hampered by the lack of diverse adjuvants for human use. Of particular interest, none of the currently available adjuvants induce Th17 cells. Here, we develop and test an improved liposomal adjuvant, termed CAF(R)10b, that incorporates a TLR-9 agonist. In a head-to-head study in non-human primates (NHPs), immunization with antigen adjuvanted with CAF(R)10b induced significantly increased antibody and cellular immune responses compared to previous CAF(R) adjuvants, already in clinical trials. This was not seen in the mouse model, demonstrating that adjuvant effects can be highly species specific. Importantly, intramuscular immunization of NHPs with CAF(R)10b induced robust Th17 responses that were observed in circulation half a year after vaccination. Furthermore, subsequent instillation of unadjuvanted antigen into the skin and lungs of these memory animals led to significant recall responses including transient local lung inflammation observed by Positron Emission Tomography-Computed Tomography (PET-CT), elevated antibody titers, and expanded systemic and local Th1 and Th17 responses, including >20% antigen-specific T cells in the bronchoalveolar lavage. Overall, CAF(R)10b demonstrated an adjuvant able to drive true memory antibody, Th1 and Th17 vaccine-responses across rodent and primate species, supporting its translational potential.

immunology↗

SARS-CoV-2 mechanistic correlates of protection: insight from modelling response to vaccines

The definition of correlates of protection is critical for the development of next generation SARS-CoV-2 vaccine platforms. Here, we propose a new framework for identifying mechanistic correlates of protection based on mathematical modelling of viral dynamics and data mining of immunological markers. The application to three different studies in non-human primates evaluating SARS-CoV-2 vaccines based on CD40-targeting, two-component spike nanoparticle and mRNA 1273 identifies and quantifies two main mechanisms that are a decrease of rate of cell infection and an increase in clearance of infected cells. Inhibition of RBD binding to ACE2 appears to be a robust mechanistic correlate of protection across the three vaccine platforms although not capturing the whole biological vaccine effect. The model shows that RBD/ACE2 binding inhibition represents a strong mechanism of protection which required significant reduction in blocking potency to effectively compromise the control of viral replication. One Sentence SummaryA framework for modelling the immune control of viral dynamics is applied to quantify the effect of several SARS-CoV-2 vaccine platforms and to define mechanistic correlates of protection.

immunology↗

Immunization with synthetic SARS-CoV-2 S glycoprotein virus-like particles protects Macaques from infection

The SARS-CoV-2 pandemic causes an ongoing global health crisis, which requires efficient and safe vaccination programs. Here, we present synthetic SARS-CoV2 S glycoprotein-coated liposomes that resemble in size and surface structure virus-like particles. Soluble S glycoprotein trimers were stabilized by formaldehyde cross-linking and coated onto lipid vesicles (S-VLP). Immunization of cynomolgus macaques with S-VLPs induced high antibody titers and TH1 CD4+ biased T cell responses. Although antibody responses were initially dominated by RBD specificity, the third immunization boosted non-RBD antibody titers. Antibodies showed potent neutralization against the vaccine strain and the Alpha variant after two immunizations and robust neutralization of Beta and Gamma strains. Challenge of animals with SARS-CoV-2 protected all vaccinated animals by sterilizing immunity. Thus, the S-VLP approach is an efficient and safe vaccine candidate based on a proven classical approach for further development and clinical testing.

immunology↗

Two-component spike nanoparticle vaccine protects macaques from SARS-CoV-2 infection

The SARS-CoV-2 pandemic is continuing to disrupt personal lives, global healthcare systems and economies. Hence, there is an urgent need for a vaccine that prevents viral infection, transmission and disease. Here, we present a two-component protein-based nanoparticle vaccine that displays multiple copies of the SARS-CoV-2 spike protein. Immunization studies show that this vaccine induces potent neutralizing antibody responses in mice, rabbits and cynomolgus macaques. The vaccine-induced immunity protected macaques against a high dose challenge, resulting in strongly reduced viral infection and replication in upper and lower airways. These nanoparticles are a promising vaccine candidate to curtail the SARS-CoV-2 pandemic.

immunology↗