ABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began churning out incredulous terror in December 2019. Within several months from its first detection in Wuhan, SARS-CoV-2 spread to the rest of the world through droplet infection, making it a pandemic situation and a healthcare emergency across the globe. The available treatment of COVID-19 was only symptomatic as the disease was new and no approved drug or vaccine was available. Another challenge with COVID-19 was the continuous mutation of the SARS-CoV-2 virus. Some repurposed drugs, such as hydroxychloroquine, chloroquine, and remdesivir, received emergency use authorization in various countries, but their clinical use is compromised with either severe and fatal adverse effects or nonavailability of sufficient clinical data. Molnupiravir was the first molecule approved for the treatment of COVID-19, followed by Paxlovid™, monoclonal antibodies (MAbs), and others. New molecules have variable therapeutic efficacy against different variants or strains of SARS-CoV-2, which require further investigations. The aim of this review is to provide in-depth information on new molecules and repurposed drugs with emphasis on their general description, mechanism of action (MOA), correlates of protection, dose and dosage form, route of administration, clinical trials, regulatory approval, and marketing authorizations.
ABSTRACT
COVID-19 caused by coronavirus SARS-CoV-2 became a serious threat to humankind for the past couple of years. The development of vaccine and its immediate application might be the only to escape from the grasp of this demoniac pandemic. Approximately 343 clinical trials on COVID-19 vaccines are ongoing currently, and almost all countries are motivating ongoing researches at warp speed for the development of vaccines against COVID-19. This review explores the progress in the development of the vaccines, their current status of ongoing clinical research, mechanisms, and regulatory approvals. Many pharmaceutical companies are already in the endgame for manufacturing various vaccines of which some are already being marketed across the globe, while others are yet to get approval for marketing. The primary aim of this review is to compare regulatory accepted vaccines in terms of their composition, doses, regulatory status, and efficacy. The study is conducted by grouping into approved and unapproved vaccines for marketing. Different routes of administration of vaccines along with the efficacy of the routes are also presented in the review. A wide range of database and clinical trial data is reviewed for sorting out the information on different vaccines. Unfortunately, many mutations (alpha, beta, gamma, delta, kappa, omicron etc.) of SARS-CoV-2 have attacked people in very short time, which is the great challenge for investigational vaccines. Moreover, some vaccines like Pfizer's BNT162, Oxford's ChAdOx1, Moderna's mRNA-1273, and Bharat Biotech's Covaxin have got regulatory approval in some countries for its distribution which may prove to stand tall against the pandemic.