Covid Arsenal Needs Pills as Well as Shots
By Scott Gottlieb and Mark McClellan
More than 60 million Americans are fully vaccinated for Covid-19, and the number rises daily. But some people aren’t willing or easily able to get vaccinated, and others won’t be able to get the shot for medical reasons, such as immune suppression. Another good weapon for the Covid arsenal would be a safe and effective drug that could be taken at home. Such outpatient drugs exist to prevent and treat the flu, and one public-health focus should be developing a Covid pill that could be taken after exposure, or soon after symptoms appear, to stop the infection from progressing.
So far outpatient treatment options have been either therapeutic antibodies or repurposed medicines off the shelf. Antibodies, when given early, are very effective at preventing Covid hospitalizations and reducing the severity of symptoms. But they’re hard to administer outside a hospital setting, currently requiring time-consuming infusions. Manufacturers and public-health leaders should focus on research to make these infusions fast and easier, and to develop one-time shots that could also be used for prevention.
A few repurposed drugs work, such as remdesivir and the steroid dexamethasone, which reduces the risk of death in patients who require oxygen or mechanical ventilation. More studies will help suss out the benefits of repurposed drugs, but so far many of these options have failed to show benefit in preventing mild Covid from progressing when studied in well-designed trials.
The National Institutes of Health should support further research for pills engineered to interrupt how the coronavirus replicates, which would be a hedge against mutations. Vaccines and antibody drugs work by targeting surface proteins on the virus. But the novel coronavirus can alter parts of these proteins through genetic mutation. What is concerning about the mutations in Brazil, South Africa, California and New York is that the virus figured out how to tweak an important region on its spike protein, one that is the target for many of the current vaccines and antibody-based therapies. Such mutations could render antibody drugs and vaccines less effective.
Enter a pill. A small-molecule drug that could block some of the core machinery that the virus uses to replicate may be able to elude these mutations. That’s because it is often harder for the virus to change the process that it uses to infect cells and replicate. Such a treatment could be an important complement to vaccines and antibody drugs, including for the small percentage of patients who may get sick despite being vaccinated. A good drug may also prevent susceptible people from developing disease after a close contact with someone infected. Such a drug can be especially useful to prevent spread when an infection occurs in a household or congregate setting.
But a potential Covid drug will present some challenges for regulators, who will want to know that the therapy can reduce progression to severe disease. Most Covid patients don’t develop severe disease, and the public will be increasingly vaccinated. Large trials may be infeasible as Covid outcomes improve and fewer patients are hospitalized.
A more feasible approach would evaluate these drugs based on their ability to shorten the duration of symptoms or reduce viral load. For a drug shown to be safe, these endpoints could support an emergency-use authorization. Full approval can be predicated on showing later that a medicine reduces the number of patients with serious consequences.
All of this could be part of a process of investing in drugs that can arrest entire classes of viruses to protect against future pandemics. A safe pill that can shut down the virus would be a game changer, helping the country return to normal life faster.
Dr. Gottlieb is a resident fellow at the American Enterprise Institute and was commissioner of the Food and Drug Administration, 2017-19. Dr. McClellan is director of the Duke-Margolis Center for Health Policy at Duke University and was FDA commissioner, 2002-04. Dr. Gottlieb serves on the boards of Pfizer and Illumina ; Dr. McClellan serves on the boards of Johnson and Johnson and Cigna ; each company is involved in aspects of the Covid response.