ABSTRACT
Tetrandrine (TET) has been used to treat silicosis in China for decades. The aim of this study was to facilitate rational repurposing of TET against SARS-CoV-2 infection. In this study, we confirmed that TET exhibited antiviral potency against SARS-CoV-2 in the African green monkey kidney (Vero E6), human hepatocarcinoma (Huh7), and human lung adenocarcinoma epithelial (Calu-3) cell lines. TET functioned during the early-entry stage of SARS-CoV-2 and impeded intracellular trafficking of the virus from early endosomes to endolysosomes. An in vivo study that used adenovirus (AdV) 5-human angiotensin-converting enzyme 2 (hACE2)-transduced mice showed that although TET did not reduce pulmonary viral load, it significantly alleviated pathological damage in SARS-CoV-2-infected murine lungs. The systemic preclinical pharmacokinetics were investigated based on in vivo and in vitro models, and the route-dependent biodistribution of TET was explored. TET had a large volume of distribution, which contributed to its high tissue accumulation. Inhaled administration helped TET target the lung and reduced its exposure to other tissues, which mitigated its off-target toxicity. Based on the available human pharmacokinetic data, it appeared feasible to achieve an unbound TET 90% maximal effective concentration (EC90) in human lungs. This study provides insights into the route-dependent pulmonary biodistribution of TET associated with its efficacy.
ABSTRACT
INTRODUCTION: The efficacy of molnupiravir (MLN) on Omicron sublineages is limited. We investigated the effectiveness of MLN in older adults diagnosed with Omicron BA.2. METHODS: Data of elderly COVID-19 patients (over 60 years) admitted to Chinghai Hospital (Shanghai, China) from 26 March to 31 May 2022 were reviewed. Study outcomes were a composite of undetectable viral load (VL) and disease progression [all-cause mortality, initiation of oxygen supply through high-flow device or invasive mechanical ventilation (IMV), or intensive care unit (ICU) admission] and their individual outcomes. RESULTS: A total of 42 elderly patients were enrolled: 26 of them received MLN, 17 (40.5%) were males, the median age was 84 years, and 12 were fully vaccinated (31.0%). Among these elderly COVID-19 patients, five (11.90%) experienced obvious dyspnea or were transferred to ICU [three MLN users (11.5%) versus two non-MLN users (12.5%)]. Compared with no MLN use, MLN use was associated with rapid undetectable VL. At day 10, MLN users achieved significantly greater undetectable VL than non-MLN users. Adjusted analysis showed that elderly patients who received MLN were 7.584 times more likely to achieve undetectable VL at day 10 than non-MLN users. Overall, elderly patients experienced a median hospital stay of 13 days. Compared with patients receiving standard care (SC), the median hospital stay of MLN users was reduced by 2.5 days. CONCLUSION: Early initiation of MLN in elderly COVID-19 was associated with fast undetectable VL and short hospital stay.
ABSTRACT
SARS-CoV-2 has been widely spread around the world and COVID-19 was declared a global pandemic by the WHO. Limited clinically effective antiviral drugs are available now. The development of anti-SARS-CoV-2 drugs has become an urgent work worldwide. At present, potential therapeutic targets and drugs for SARS-CoV-2 are continuously reported, and many repositioning drugs are undergoing extensive clinical research, including remdesivir and chloroquine. On the other hand, structures of many important viral target proteins and host target proteins, including that of RdRp and Mpro were constantly reported, which greatly promoted structure-based drug design. This paper summarizes the current research progress and challenges in the development of anti-SARS-CoV-2 drugs, and proposes novel short-term and long-term drug research strategies.