Novel Antiviral Strategies in the Treatment of COVID-19: A Review

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus-2 (SARS–CoV-2), is still a global public health problem for humans. It has caused more than 10,000,000 infections and more than 500,000 deaths in the world so far. Many scientists have tried their best to discover safe and effective drugs for the treatment of this disease; however, there are still no approved standard therapeutics or effective antiviral drugs on the market. Many new drugs are being developed, and several traditional drugs that were originally indicated or proposed for other diseases are likely to be effective in treating COVID-19, but their safety and efficacy are controversial, under study, or in clinical trial phases. Fortunately, some novel antiviral strategies, such as convalescent plasma, clustered regularly interspaced short palindromic repeats (CRISPR), and mesenchymal stem cell (MSC) therapy, potentially offer an additional or alternative option or compassionate use for the people suffering from COVID-19, especially for critically ill patients, although their safety and efficacy are also under study. In this review, we explore the applications, possible mechanisms, and efficacy in successful cases using convalescent plasma, CRISPR, and MSC therapy for COVID-19 treatment, respectively. Furthermore, the perspectives and limitations of these novel antiviral strategies are evaluated.