Two clinical trials involving more than 1,600 patients have shown effects ranging from none to modest. It is difficult to imagine that the hopes of remdesivir being a silver bullet to conquer COVID will ever be realized, at least not as an IV treatment for hospitalized patients. But it is still possible that the drug hasn’t been given a fair shake. As a direct-acting antiviral, early administration is important and no patients in either of these trials were given the drug until they were already hospitalized and quite ill. It is possible (perhaps even likely) that no antiviral drug, no matter how potent, will be able to alter the course of COVID when given days/weeks after the start of the infection. Perhaps the best shot for remdesivir would be very early administration, perhaps as in inhaled powder after a rapid diagnostic saliva test. (Gilead is working on a dry powder formulation.)
Or, more likely, as is the case in drug discovery, the first drug to treat a condition or infection is rarely the best. The first HIV/AIDS drug, AZT, did little or nothing to prolong the lives of AIDS patients after one year of therapy. The first direct-acting hepatitis C drugs, boceprevir and telaprevir (2011) were relegated to the antiviral scrap heap within a couple of years as they were replaced by the much superior Sovaldi, which itself has been replaced by more potent drug combinations. Such is the nature of drug discovery,
If a game-changing COVID antiviral drug is ever found, it is quite possible that it doesn’t exist yet.