What happened Johnson & Johnson (NYSE: JNJ) closed 3.6% lower on Friday. A downward move is exactly the opposite of what you'd expect to happen when a coronavirus vaccine developer announces positive clinical trial results, as the company did that morning. So what Data indicated that Johnson & Johnson's candidate met all of the primary and key secondary endpoints in its phase 3 clinical trial. In the sprawling global study, the vaccine's overall efficacy was 66% in blocking moderate to severe COVID-19. It was 85% effective in preventing severe forms of the disease. Image source: Getty Images. Better yet, the vaccine's "efficacy against severe disease increased over time, with no cases in vaccinated participants reported after day 49," as the company wrote. It also showed complete protection against hospitalization and death from the disease 28 days after vaccination. No significant safety concerns were reported, and the vaccine was well-tolerated. One advantage of the pharmaceutical giant's vaccine is that it is administered in a single dose, as opposed to the two-shot vaccines currently authorized in the U.S. Johnson & Johnson plans to file for an emergency use authorization (EUA) from the Food and Drug Administration in early February. Now what An inoculation efficacy rate of 66% is not as good as that of the competition. The Moderna and Pfizer/BioNTech vaccines both had significantly higher rates (94.1% and 95%, respectively). Still, 66% is considered to be a strong result. Plus, Johnson & Johnson's testing involved more contagious variants of the coronavirus. Moderna and Pfizer/BioNTech's results came before the spread of those variants. All in all, this was excellent news for Johnson & Johnson, so the sell-off seems undeserved. 10 stocks we like better than Johnson & JohnsonWhen investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* David and Tom just revealed what they believe are the ten best stocks for investors to buy right now... and Johnson & Johnson wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks *Stock Advisor returns as of November 20, 2020 Eric Volkman has no position in any of the stocks mentioned. The Motley Fool recommends Johnson & Johnson and Moderna Inc. The Motley Fool has a disclosure policy.Source