Despite growing public health concerns over the long-term ramifications of some people choosing not to get vaccinated, COVID-19 vaccination rates have been steadily rising across the country . Over the past year, clear advances have been made in developing and administering state-of-the-art vaccines, and a recent drug by Merck puts forth a new possible avenue of COVID-19 protection: an oral antiviral pill.
The drug, officially named molnupiravir, was first developed as preventative medicine and treatment for SARS-CoV and MERS in the early 2000s. The drug was brought forth to the science community spotlight after promising initial results which showed patients being half as likely to be hospitalized as those taking the placebo. The treatment group was tasked to take four pills twice a day for five days, and while eight patients within the placebo group died, none within the treatment group did. Seven percent of patients in the treatment group were either hospitalized or died through 29 days compared with 14% of patients in the placebo group. Five days after dose administration, none of those who received the dose tested positive for the virus compared with 24% of the placebo group. Finally, molnupiravir was shown to be functional against SARS-CoV-2 variants such as Gamma, Delta and Mu amongst the 40% of participants who were available for viral sequencing . Although this data is preliminary and pertains to a rather small sample size, Merck decided to put forth an Emergency Use Authorization to the FDA to conduct larger-scale studies on the effects of molnupiravir and ultimately acquire regulatory clearance. This clearance involves having permission to start wide scale production and distribution of the drug.
Regarding the mechanism behind the pill, Merck has stated that molnupiravir is a “form of a ribonucleoside analog that inhibits the replication of SARS-CoV-2” . In terms of the morphology of the compound, molnupiravir is classified as a tautomer, meaning it assumes two base pair forms: uracil and cytosine. Therefore, once recopied in cells containing SARS-CoV-2, RNA polymerase develops transition mutations where cytosine nucleotides are converted to uracil and vice versa. Furthermore, the normal RNA repair functions are unable to observe and attend to these mutations given how small they are . SARS-CoV-2 needs to propagate within the body to effectuate harm, so by creating mutations in the RNA replication process of the virus, the virus is unable to replicate amongst cells and therefore does not have the capacity to spread through the body . A recent study on molnupiravir has noted a statistically significant relationship between virus production and dose levels, an inability of the virus to develop resistance to molnupiravir by consequence of the induced random mutations, and a broad applicability of molnupiravir to other viruses such as the Venezuelan Encephalitis Virus, Influenza A and B and Ebola based upon the examination of lung viral loads and pulmonary function in mouse models of SARS-CoV, MERS-CoV and SARS-CoV-2 .
In all, Merck has put forth a promising COVID-19 drug that could serve as an additional COVID-19 therapy. Its relatively convenient oral administration lends itself as a possible treatment for hospitalized patients or even as a preventative treatment. It is important to note that while Merck and other scientific contributors have put forth Molnupiravir as a promising treatment, the data is far from conclusive. Going forward, it is of the utmost importance for the scientific community to continue conducting longitudinal, large-scale human clinical trials of Molnupiravir to understand the long-term effects of the drug on humans. For now, and going forward, treatments such as the Pfizer and Moderna vaccines are the most legitimate and effective means to fight COVID-19.
Edited by: Isaac Mordukhovich