A Word In Edgewise: Where There’s a Pill There’s a Way?

As we round into a third year, so does the SARS-CoV-2 virus, at this writing, mutated beyond Delta into its Omicron edition. While human scientists, virologists and researchers toil diligently to curtail the pandemic, the virus ceaselessly, relentlessly seeks new means to enter human cells and hijack host RNA, re-plicate, proliferate. 

There’s been work on Covid pills, and a recent article on yalemedicine.org in which Drs. and Yale Medicine infectious disease specialists Albert Shaw and Jaimie Meyer discuss the development and potential of molnupiravir, what this drug is designed to do and through what mechanism. 

The most important message I gleaned is that this pill, being developed by Merck, and almost approved by the FDA last November, is designed to be used after Covid symptoms appear, in a course of four capsules twice daily over five days. Like the existing Remdesivir, or like monoclonal antibodies IV, the new drug bocks the ability of SARS-CoV-2 virus to replicate, but it uses a different mechanism. 

Rather than blocking viral entry into the human cell, molnupiravir works from within. The virus uses host RNA as genetic building material, and molnupiravir is designed to resemble those chemical building blocks (nucleosides), and incorporates itself into the RNA being synthesized by the virus. As this RNA is being translated into viral proteins, too many mutations are created, and prevent the virus from functioning. 

One question of side effects would be, if the molnupiravir can disrupt viral RNA replication, might it also affect existing human RNA or DNA? No pregnant or lactating women were enrolled in the tests to prevent possible fetal RNA involvement, and men were told not to have unprotected sex for a week after completing the course. Only unvaccinated subjects were involved in the tests. 

Seeing the word “pill,” the mind jumps to “cure” or “prevention,” but molnupiravir is a catch-up, post-symptom drug, whose goal, cautions Dr. Meyer, is to keep people who are already evincing symptoms “out of the hospital.” It has been tested, so far, only on older, high-risk individuals. 

Merck has sought an EUA (emergency use authorization) from the FDA for high-risk adults, the criteria involving age, history of diabetes, heart disease, obesity and others. Tamiflu, an antiviral used to prevent serious flu symptoms, is a “post-exposure prophylaxis,” or “PEP,” that works by preventing the influenza virus from entering an exposed host’s cells. Molnupiravir is used after a patient shows actual symptoms. Dr. Meyer expressed hope that molnupiravir, as yet to be tested as a PEP, will be so in the future. 

The Guardian also wrote of Paxlovid, another, post-symptom anti-Covid pill in development, but while it mentioned a similar five-day pill course with a low dose of ritonavir, and mentioned “lab tests,” it did not specify which labs or the company of origin. 

The Yale Medicine article written by Kathy Katella on December 1st was originally published on October 11th, 2021. News and updates happen quickly in this field, as they must when reporting on an enemy working 24/7 to circumvent human efforts. Keeping informed is a task in itself, but simple precautions are within everyone’s reach. Mask around others, keep socially distant, handwash. Human boredom is understandable, but Covid virus is ever alert, ever adapting. You’re in Vegas, now, and odds are always with the house.