This is in part the case because trial drugs are typically rated on whether they reduce hospital admissions. But hospitalization rates may not be the only, nor the best measure of clinical trials – not when time is of the essence. Hospitalization rates for Covid-19 patients involved in early treatment trials in the United States have tended to be less than 5%, meaning that a study that hopes to demonstrate a statistically significant difference between a drug and a placebo requires the participation of more than 1,000 people.
Parameters other than lower hospitalization rates could be defined to evaluate the trials; one of them might be to determine whether certain drugs shorten the duration of a patient’s symptoms. Such criteria would allow for still rigorous but much faster tests involving, for example, less than 100 participants. Smaller, more nimble studies would also facilitate comparison between more promising drugs, all with a view to bringing effective drugs to market as quickly as possible.
The most crucial area where the pursuit of perfection could come at the expense of the common good is vaccine development, evaluation and licensing.
As with antiviral therapies, a vaccine should not be released to the public without first demonstrating its safety and efficacy in randomized, double-blind, placebo-controlled clinical trials. But the problem, again, is how we choose to define efficiency.
The United States Food and Drug Administration generally approves vaccines that are at least 50 percent effective in preventing disease. But even a vaccine that was less effective than that could dramatically reduce the number of coronavirus infection cases and deaths linked to Covid-19, if rolled out quickly enough and given to people most likely to be infected first or infect other people. As others have argued, vaccines don’t just prevent disease; they can prevent the pathogen that causes it from spreading.
Mass vaccination programs benefit not only those who are vaccinated but also everyone else because they are less likely to come into contact with an infected person. For example, widespread inoculation of children in the United States with a vaccine against the pneumococcal bacteria, a common cause of pneumonia, has been shown to reduce deaths and hospitalizations from the disease in adults.
Likewise, some of the people most at risk of developing severe cases of Covid-19 – the elderly, the immunocompromised – may not respond adequately to a vaccine. But they could nevertheless be protected by only one if a sufficient proportion of the total population were inoculated with it.