[Three decades of the hepatitis C virus from the discovery to the potential global elimination: the success of translational researches]

Repurposing drugs for treatment of SARS-CoV-2 infection: computational design insights into mechanisms of action

The COVID-19 pandemic has negatively affected human life globally. It has led to economic crises and health emergencies across the world, spreading rapidly among the human population and has caused many deaths. Currently, there are no treatments available for COVID-19 so there is an urgent need to develop therapeutic interventions that could be used against the novel coronavirus infection. In this research, we used computational drug design technologies to repurpose existing drugs as inhibitors of SARS-CoV-2 viral proteins. The Broad Institute's Drug Repurposing Hub consists of in-development/approved drugs and was computationally screened to identify potential hits which could inhibit protein targets encoded by the SARS-CoV-2 genome. By virtually screening the Broad collection, using rationally designed pharmacophore features, we identified molecules which may be repurposed against viral nucleocapsid and non-structural proteins. The pharmacophore features were generated after careful visualisation of the interactions between co-crystalised ligands and the protein binding site. The ChEMBL database was used to determine the compound's level of inhibition of SARS-CoV-2 and correlate the predicted viral protein target with whole virus in vitro data. The results from this study may help to accelerate drug development against COVID-19 and the hit compounds should be progressed through further in vitro and in vivo studies on SARS-CoV-2.

Outcomes of first versus third kidney transplantations: propensity score matching and paired subgroup analysis-a single-centre experience

Background

In the Eurotransplant, 12.6% of kidney transplantations are a repeat procedure. Third transplants are significantly more complex than first and second ones. We compared the results of first (PRT) versus third (TRT) transplantations.

Methods

Between 2011 and 2016, we performed 779 deceased donor adult kidney transplantations, 14.2% out of them were second, 2.6% (20) third, and 0.3% fourth. We compared the pre-, intra-, and postoperative data, kidney function, and survival rate.

Results

Recipients of TRT were younger (53.4 vs. 47.3 p = 0.02). HCV infection rate (20%, p = 0.00) is ten times higher. The operation time is longer (132 vs. 152 min, p = 0.02), and delayed graft function is much more frequent (22.4% vs. 60%, p = 0.00). Induction therapy was given to every TRT (7.9% vs.100%), but as a result, the rejection rate was the same (~ 15%). Hospital stay is a week longer. Patient’s survival at 1, 3, and 5 years for PRT is 96.4%, 93.9%, and 91.2% and for TRT is 90%, 85%, and 78.4%, respectively (p = 0.023). TRT’s odds ratio of fatal outcome is 4.35 (1.5–12.5). Graft survival at 1, 3, and 5 years for PRT is 93.1%, 91.4%, and 90.3% and for TRT is 75%, 75%, and 75%, respectively (p = 0.020). TRT’s odds ratio of graft loss is 3.14 (1.1–8.9). Of PRT 85.76%, out of PRT 85.76%, while out of TRT 60% live with a functioning graft, p=0.00149.

Conclusion

In a third transplant, both graft and patient survival are significantly inferior to primer ones. Careful selection is required to minimize the patient risk and graft loss.

Identification of potential inhibitors of three key enzymes of SARS-CoV2 using computational approach

The recent outbreak of coronavirus disease-19 (COVID-19) continues to drastically affect healthcare throughout the world. To date, no approved treatment regimen or vaccine is available to effectively attenuate or prevent the infection. Therefore, collective and multidisciplinary efforts are needed to identify new therapeutics or to explore effectiveness of existing drugs and drug-like small molecules against SARS-CoV-2 for lead identification and repurposing prospects. This study addresses the identification of small molecules that specifically bind to any of the three essential proteins (RdRp, 3CL-protease and helicase) of SARS-CoV-2. By applying computational approaches we screened a library of 4574 compounds also containing FDA-approved drugs against these viral proteins. Shortlisted hits from initial screening were subjected to iterative docking with the respective proteins. Ranking score on the basis of binding energy, clustering score, shape complementarity and functional significance of the binding pocket was applied to identify the binding compounds. Finally, to minimize chances of false positives, we performed docking of the identified molecules with 100 irrelevant proteins of diverse classes thereby ruling out the non-specific binding. Three FDA-approved drugs showed binding to 3CL-protease either at the catalytic pocket or at an allosteric site related to functionally important dimer formation. A drug-like molecule showed binding to RdRp in its catalytic pocket blocking the key catalytic residues. Two other drug-like molecules showed specific interactions with helicase at a key domain involved in catalysis. This study provides lead drugs or drug-like molecules for further in vitro and clinical investigation for drug repurposing and new drug development prospects.