When set against efficacy data of the mRNA-based coronavirus vaccines developed by Moderna (MRNA 1.17%) and Pfizer (PFE -0.78%), which proved about 95% effective at keeping coronavirus infections at bay, Johnson & Johnson's (JNJ 0.49%) vaccine's results might not have inspired much optimism. The company's adenovirus vector vaccine was shown to be 66% effective at preventing moderate to severe COVID-19 in phase 3 trials.
But once we look deeper, the vaccine data is actually incredibly promising. Not to mention, there are plenty of logistical reasons why a one-dose vaccine could be a big winner. Johnson & Johnson has pledged not to profit off its vaccine during the pandemic, but once the public health crisis subsides, there could still be spoils left for the healthcare giant. Here's why that "66%" is not the red flag you might think it is.