Long shots, moonshots, and your shots

In the race to defeat the coronavirus, the finish line is the mass production of a safe, effective vaccine.

Just as Jonas Salk’s vaccine helped transform polio from feared menace to historical curiosity in most countries, a good vaccine against today’s coronavirus would restore the world’s confidence, both socially (potlucks! concerts! sports!) and economically. So where does the vaccine race stand now?

The U.S. federal government’s unprecedented Operation Warp Speed project involves building factories to produce yet-unproven vaccines. That will allow the vaccines to come to market quickly if studies bear out their effectiveness. The Food and Drug Administration is speeding up the normal multiyear approval process with a “rolling review” that evaluates safety data as it comes in. (Here’s an excellent graphical summary.) The FDA has decided that, to be approved, a vaccine must make people 50 percent less likely to contract coronavirus or must reduce symptoms by 50 percent.

The nearly 150 coronavirus vaccine research projects—as of the World Health Organization’s latest count—have the same goal, but differ in their methods: Should a vaccine use an inactivated strain of the now-circulating SARS-CoV-2? Or should it use another, less dangerous virus, genetically modified to appear similar enough to the coronavirus that it will fool the person’s immune system? What if the vaccine doesn’t use a virus at all, but rather a protein the virus makes, or the messenger RNA (“mRNA”) that encodes a protein?

The World Health Organization (WHO) lists 19 vaccine candidates as having started human clinical trials as of July 6—with 130 more in pre-clinical animal studies. (Clinical research typically begins in phase 1, involving dozens of participants, and progresses to phase 3, involving thousands.)

Thinking even further outside the box, an Australian-led team is investigating a long-known phenomenon in which the bacillus Calmette-Guérin (BCG) vaccine, used to prevent tuberculosis in the developing world, seems to boost immunity more generally. Could it reduce the chances of severe COVID-19 infection? This team had a head start, since BCG has undergone extensive study over the years. Since the only question is whether it protects against the coronavirus, the team went straight to a phase 3 trial.

If we count the repurposed BCG vaccine along with Oxford’s, Sinovac’s, and Moderna’s coronavirus-specific vaccines, the end of July will likely see four phase 3 trials progressing simultaneously—with several more planned in months to come. Even the first trials won’t finish until fall, and successful mass production doesn’t mean instantaneous availability. But accelerated approval and pre-built factories should limit delays if one or more of the candidates prove worthy.

“This is not the end. It is not even the beginning of the end,” as Churchill once said. “But it is, perhaps, the end of the beginning.”