Phase 3 Trial season is here: the final lap of the Covid-19 vaccine race

Good things come in (phase) threes?... TBD. Out of the 170 Covid-19 vaccines in development, 35 have been approved for clinical human trials. Out of those, only 9 have advanced into the final phase of trials (aka Phase 3). Now the drugmakers are aiming to seek regulatory approval or emergency-use authorization as soon as October. Three of the Phase 3 front-runners:

• AstraZeneca: Is aiming to wrap up Phase 3 next month. It just resumed trials after briefly pausing due to an illness in a volunteer (apparently unrelated).
• Pfizer: If its vaccine with BioNTech proves safe, it would be the 1st mRNA vaccine ever approved (unless Moderna gets there first).
• Moderna: Its final stage trial could yield interim results in the fall.

The stakes... need little explanation. A vaccine is critical to stopping this world-shattering pandemic that has killed ~920K people. And it all hinges on Phase 3 results. These large-scale trials (usually 30K people) test whether the dose that would be given to the public is safe. BTW: Russia's vaccine skipped this final stage.

• While Phase 3 could go on for a while, positive mid-trial results could be enough for a vaccine to start getting approval for mass production and distribution in October.
• Vaccines usually take 6-10 years from development to approval. The US has invested over $10B in "Operation Warp Speed" to make that happen in less than a year.