Therapeutic Effectiveness and Safety of Repurposing Drugs for the Treatment of COVID-19: Position Standing in 2021

Abstract

COVID-19, transmitted by SARS-CoV-2, is one of the most serious pandemic situations in the history of mankind, and has already infected a huge population across the globe. This horrendously contagious viral outbreak was first identified in China and within a very short time it affected the world's health, transport, economic, and academic sectors. Despite the recent approval of a few anti-COVID-19 vaccines, their unavailability and insufficiency along with the lack of other potential therapeutic options are continuing to worsen the situation, with valuable lives continuing to be lost. In this situation, researchers across the globe are focusing on repurposing prospective drugs and prophylaxis such as favipiravir, remdesivir, chloroquine, hydroxychloroquine, ivermectin, lopinavir-ritonavir, azithromycin, doxycycline, ACEIs/ARBs, rivaroxaban, and protease inhibitors, which were preliminarily based on in vitro and in vivo pharmacological and toxicological study reports followed by clinical applications. Based on available preliminary data derived from limited clinical trials, the US National Institute of Health (NIH) and USFDA also recommended a few drugs to be repurposed i.e., hydroxychloroquine, remdesivir, and favipiravir. However, World Health Organization later recommended against the use of chloroquine, hydroxychloroquine, remdesivir, and lopinavir/ritonavir in the treatment of COVID-19 infections. Combining basic knowledge of viral pathogenesis and pharmacodynamics of drug molecules as well as in silico approaches, many drug candidates have been investigated in clinical trials, some of which have been proven to be partially effective against COVID-19, and many of the other drugs are currently under extensive screening. The repurposing of prospective drug candidates from different stages of evaluation can be a handy wellspring in COVID-19 management and treatment along with approved anti-COVID-19 vaccines. This review article combined the information from completed clinical trials, case series, cohort studies, meta-analyses, and retrospective studies to focus on the current status of repurposing drugs in 2021.

The Immunology of SARS-CoV-2 Infection and Vaccines in Solid Organ Transplant Recipients

“…Remdesivir, a nucleotide analog that resembles adenosine triphosphate (ATP) and thus inhibits virus RNA synthesis, was considered a potential treatment option for RNA viruses, including SARS-Cov-2. Initial clinical reports indicated clinical and antiviral efficacy as a part of multidrug therapy in severe COVID-19 cases [ 75 ]. However, a recent meta-analysis showed that remdesivir had no effect on mortality in hospitalized COVID-19 patients [ 76 ] but may increase the recovery percentage and decrease the ventilation requirement rate.…”

Comparative kinetics of SARS-CoV-2 anti-spike protein RBD IgGs and neutralizing antibodies in convalescent and naïve recipients of the BNT162b2 mRNA vaccine versus COVID-19 patients

“…Given that currently there is no effective treatment for COVID-19 [ 3 , 12 ], a prophylactic intervention via vaccination is deployed via a worldwide campaign. The BNT162b2 mRNA vaccine (Comirnaty TM ; Pfizer-BioNTech GmbH) is the first vaccine that received emergency use authorization by both FDA and EMA, due to its efficacy in healthy adults [ 13 ], while reportedly it also induces cross-neutralization of at least some of the circulating SARS-CoV-2 variants [ 14 – 16 ].…”

Traditional Uses, Nutritional and Pharmacological Potentials of Clerodendrum volubile

“…As the COVID-19 pandemic spreads globally, research scientists and policymakers are making continual efforts to curtail the transmission by consistent public health interventions, such as through the use of a nose mask, washing of hands, social distancing, testing of suspected cases, and isolation [ 82 , 83 ]. Interestingly, repurposed drugs, such as remdesivir, ritonavir, chloroquine, and lopinavir, among others, are being used in the management of COVID-19 infection [ 84 ]. In addition, the use of supplements that can boost the host immune system has been documented as a good strategy to fight the virus [ 85 ].…”