Shares of Moderna Inc. MRNA, -3.02% gained 0.5% in premarket trading on Tuesday after the company said it is seeking an update to the conditional authorization of its COVID-19 vaccine in Europe so that it includes children between the ages of 6 and 11 years old. Moderna said earlier this month that it will delay filing for authorization in this age group in the U.S. until the Food and Drug Administration's review of the myocarditis risk in teens is resolved, likely by January. Moderna's clinical data shows that its shot has an efficacy rate of 80% at preventing infection with the virus, including symptomatic and asymptomatic cases, among children in this age group two weeks after they received the second dose. Moderna's stock is up 134.2% this year, while the broader S&P 500 SPX, -0.35% has gained 25.2%.