Therapeutic potential of Paclitaxel against COVID-19

The coronavirus disease-2019(COVID-19) was reported in Wuhan, China, in late December 2019 and soon became the most serious global health challenge due to high rate of human-to-human transmission. The severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), is a single-stranded RNA virus and belongs to the large Coronaviridae family. Paclitaxel, an antineoplastic drug extracted from the Taxus brevifolia tree, is used to treat ovarian and breast cancer. It stabilizes microtubule polymer and prevents the disassembly of microtubules that leads to inhibition of cell division. There are strong evidences indicating that Paclitaxel at ultra-low non-toxic doses can inhibit inflammatory responses through different mechanisms. For instance, stabilization of endothelial microtubules, decreases neutrophil locomotion and leukocyte chemotaxis. Paclitaxel down-regulated the p38 MAPK(mitogen-activated protein kinase) signaling pathway, the nuclear factor-κB(NF-κB) and pro-inflammatory cytokines(Interleukin-1β(IL-1β), IL-6, IL-10, IL-5, IL-13, tumor necrosis factor α(TNFα), transforming growth factor β(TGFβ) and interferon γ(IFN-γ) ) in various non-neoplastic conditions. The antiviral activity of Paclitaxel, such as inhibition of human immunodeficiency virus (HIV)-1 protease, has been reported in some studies. In recent years, the induction of autophagy has been noticed as a new therapeutic target for viral diseases. It is documented that the SARS-CoV-2 virus inhibits the autophagy system for increasing self-replication and escape from elimination, which makes an efficient viral dose density for viral pathogenicity According to these evidences; the authors suggest that Paclitaxel may have therapeutic potential in COVID-19 through anti-inflammatory and possible antiviral activity.