Phytotherapic Drugs for COVID-19 Treatment: A Scoping Review.

BACKGROUND: The rapid eruption of Coronavirus at the end of 2019 has caused global health crisis and significant loss to the economy and social well-being. This created a massive shortage of advanced health facilities with inadequate medicinal supply, further deteriorating human health conditions. On the basis of adverse effects of the ongoing pandemic, this review has been proposed to evaluate the antiviral efficacy of plant- based therapeutics, against SARS-CoV-2 (commonly called COVID-19) infection. It highlights the possible action of the mechanism of phytotherapeutic drugs against coronavirus inhibition, further validated by clinical trials on herbal formulas is reviewed. Though the experimental studies on COVID-19 treatment are limited, the undesirable side effects of herbal drugs and unidentified compounds cannot be ignored. OBJECTIVE: We have made an effort to study the prospective plant-derived bioactive entities and their effectiveness in the treatment of COVID-19 and also emphasize on safety and regulatory concerns of phytomedicines. METHODS: The methodology involves relevant studies on COVID-19 treatment based on herbal extracts and the purified bioactive metabolites. The e-literature survey has been done by downloading research articles available on PubMed (National Library of medicine), Elsevier, and Google scholar search engines. The keywords used are plant metabolites, natural bioactive, phytotherapeutic drugs, clinical trials, SARS-CoV-2, Coronavirus inhibitors and herbal extracts. RESULTS: The review pays particular attention to the etiological study of the COVID-19 virus and its inhibition using medicinal plant metabolites as immunomodulatory agents. The application of valuable bioactives like phenolic compounds, saponins, alkaloids, tannins, flavonoids and terpenoids in preparing herbal formula/drug has been focused on. The drug resistance of bioactive compounds and their side effects on human health were discussed for effective phytomedicine, thus, emphasizing the perspectives of phytotherapeutic drugs as a safe remedy to boost immunomodulatory functions and antiviral activity against COVID-19. CONCLUSION: Altogether, the review presents the action mechanism of plant extracts rich in bioactive compounds and depicted potential antiviral activity against SARS-CoV-2. These plant bioactive compounds can serve as lead molecules to develop phytomedicine, ensuring all safety regulations in the clinical trials to treat or prevent COVID-19 viral infections.

The potential of ODFs as carriers for drugs/vaccines against COVID-19.

COVID-19 has spread out its wings across the globe and is taking away many lives. Millions of people are (self) quarantined to prevent the spread of this viral disease. World Health Organization (WHO) has affirmed that there is not any medicine for COVID-19. Besides, there is also no single drug that is approved by any regulatory agency for usage against this dangerous disease. Researchers across the globe are working tirelessly to fix an end to this virus and to save precious lives. While the research is in full swing, one is not sure whether they would come up with a chemical/herbal drug or a vaccine. Irrespective of the type of active ingredient for COVID-19, one needs to have a proper system to deliver the identified active ingredient to subjects/patients across the globe. Orodispersible films (ODFs) are excellent and attractive drug delivery carriers that have the potential to deliver drugs, herbal extracts, and vaccines. They are apt for patients who have a problem consuming traditional drug products such as tablets or capsules. The beauty of this dosage form is that it does not need water to consume by the subjects and can be readily administered to the tongue. The present review highlights the true potential of ODFs to act as a carrier for the delivery of various antiviral drugs/herbs/vaccines.

Phytochemicals containing biologically active polyphenols as an effective agent against Covid-19-inducing coronavirus.

The outbreak of Covid-19 disease caused by SARS-CoV-19, along with the lack of targeted medicaments and vaccines, forced the scientific world to search for new antiviral formulations. In this review, we describe the current knowledge about plant extracts containing polyphenols that inhibit Covid-19. Many plant-derived natural compounds (polyphenols) might provide a starting point for the research on the use of plant extracts in coronavirus treatment and prevention. Antivirus polyphenolic drugs can inhibit coronavirus enzymes, which are essential for virus replication and infection. This group of natural substances (betulinic acid, indigo, aloeemodine, luteolin, and quinomethyl triterpenoids, quercitin or gallates) is a potential key to designing antiviral therapies for inhibiting viral proteases. The known pharmacophore structures of bioactive substances can be useful in the elaboration of new anti-Covid-19 formulations. The benefit of using preparations containing phytochemicals is their high safety for patients and no side effects.

Polyphenols vs. Coronaviruses: How Far Has Research Moved Forward?

The epidemic, caused by SARS-CoV-2 at the beginning of 2020, led us to a serious change in our lifestyle that for about three months has confined us to our homes, far from our laboratory routine. In this period, the belief that the work of a researcher should never stop has been the driving force in writing the present paper. It aims at reviewing the recent scientific knowledge about in vitro experimental data that focused on the antiviral role of phenols and polyphenols against different species of coronaviruses (CoVs), pointing up the viral targets potentially involved. In the current literature scenario, the papain-like and the 3-chymotrypsin-like proteases seem to be the most deeply investigated and a number of isolated natural (poly)phenols has been screened for their efficacy.