Could AstraZeneca's Coronavirus Vaccine Beat Pfizer and Moderna?

If you had the option to get one of two effective coronavirus vaccines, one that costs $10 or one that costs $20, which one would you choose? Now that AstraZeneca (NASDAQ:AZN) is reporting that its candidate AZD1222 may be 90% effective at preventing coronavirus infections, people all over the world could soon face that choice. If approved vaccines are of equal quality, then choosing the cheaper option is easy. However, based on recent interim trial data, the decision could be more complicated once we consider safety and efficacy data.