In some of the first in vivo imaging experiments on COVID-19 hamster models, the research group led by Prof. Johan Neyts and Professor Greetje Vande Velde at KU Leuven moved fast to develop a Syrian hamster model for the disease to test the effectiveness of three potential COVID-19 treatments, evaluated by µCT.1 The study used the SkyScan 1278 to assess whether the antiviral favipiravir, the antimalarial hydroxychloroquine (HCQ), or HCQ combined with the antibiotic azithromycin, could mitigate the disease or prevent transmission.
Results showed that favipiravir slightly reduced viral load in hamsters directly infected with SARS-CoV-2. However, neither HCQ nor HCQ plus azithromycin affected the viral load. Additionally, the results of lung micro-CT imaging showed no clear effect for any of the treatments in reducing the lung occlusion - due to pathologies such as inflammation - associated with SARS-CoV-2 infection. Furthermore, none of the three treatments protected healthy hamsters against transmission from infected animals.
Importantly, the group successfully characterized a robust hamster infection and transmission model for studying in vivo efficacy of antiviral compounds. The information acquired using HCQ and favipiravir in this model is vital to the design of current and future COVID-19 clinical trials. The data presented here, on HCQ either alone or combined with azithromycin (together with previously reported in vivo data in macaques and ferrets) provide no scientific basis for further use of the drug in humans.
Prof Vande Velde, Principal Investigator at the core facility Molecular Small Animal Imaging Center (MoSAIC) and at the KU Leuven Faculty of Medicine, commented: "The research findings from the Neyts lab not only offer guidance on which drugs to progress through COVID-19 clinical trials, but provide evidence for the benefits of micro-CT as an indispensable and safe tool to repeatedly evaluate lung disease progression and therapy efficacy without harming live animals. Small animal infection models, such as the hamster model presented in this research, should play a pivotal role in the selection of SARS-CoV-2 treatments for clinical development."
The KU Leuven Center of Excellence for Lung Research is equipped with a range of powerful instrumentation for viral analysis and lung in-vivo imaging, including Bruker's low-dose, high-throughput SkyScan 1278 micro-CT scanner, strengthening its position to continue investigating drugs to fight COVID-19.
For more information on the SkyScan 1278 micro-CT scanner, please visit www.bruker.com/products/microtomography/in-vivo-micro/skyscan-1278/overview.html or watch our webinar on the use of micro-CT in lung disease research here.
1. Kaptein et al. (2020) Antiviral treatment of SARS-CoV-2-infected hamsters reveals a weak effect of favipiravir and a complete lack of effect for hydroxychloroquine, bioRxiv, https://doi.org/10.1101/2020.06.19.159053