The antiviral Molnupirvir, by Merck pharmaceutical, was approved for emergency use against Covid-10 in the US and India. With no double-blind randomized trials yet, Merck reported that its drug reduces the chance of hospitalization with the disease by about 30% — some Brazilian patients were included in the pilot study.
Fluvoxamine, a cheap antidepressant that has been shown to be effective in resubmission as Covid’s early treatment, has equal or greater efficacy than that reported by Merck, with the advantage that it has two double-blind studies in its favor. There is another advantage: unlike Molnupiravir, it is not an agent that causes mutations in the virus.
It seems strange, for some specialists, that a drug that could lead to new variants is proposed as a treatment. This is the opinion of Michael Lin, a Stanford professor of neurobiology and bioengineering who works on the genetic engineering of viruses. “Would you rather (1) go back to normal activities sometime, or (2) we continually make new coronaviruses that escape vaccines and wear masks forever?” Lin said on Twitter. “If you chose 1, know this: Molnupiravir from Merck must not be approved.”
The reason for concern by Lin and others is the mechanism of action of Molnupiravir. It mimics one of the building blocks of the virus’s genetic material. So when the virus tries to replicate, it mutates. In the laboratory, the effect of this is to inactivate the virus, as most mutations are bad for it. However, in human organisms, considering the inevitable variation in the presence of the drug in the organism, mutations that favor viral replication could be maintained — it is Darwin’s process of natural selection that leads to adaptation.15172212Molnupiravir and the omicron variant
William Haseltine, professor of medicine at Harvard for nearly two decades and president of the health NGO ACCESS, raised hypotheses for the emergence of the variant omicron in Forbes magazine: it may have come from an immunocompromised patient where the virus has more opportunity to diversify, it may have jumped from humans to other animals and back to humans (we know that the SARS-CoV-2 virus is capable of infecting deer , dogs, cats and other animals), or may have come from a patient treated with Molnupiravir who did not take the full dose.