Shares of Novavax Inc. /zigman2/quotes/202614340/composite NVAX -3.89% surged 4.4% toward a two-month high in morning trading Tuesday, to buck the selloff in the broader stock market, after the biotechnology company said its COVID-19 vaccine Nuvaxovid received expanded conditional marketing authorization (CMA) from the European Commission (EC) for people aged 12 through 17. Novavax's COVID vaccine has not yet been authorized for use in the U.S., and the trade name Nuvaxovid has not yet been approved by the U.S. Food and Drug Administration. The company said the EU authorization was based on data showing the vaccine was well tolerated, and shoed 80% clinical efficacy at a time that the delta variant was dominant. "With this authorization, we are extremely pleased to be able to offer our Nuvaxovid COVID-19 vaccine to adolescents in the EU," said Chief Executive Stanley Erck. The stock has tumbled 58.3% year to date, while the iShares Biotechnology ETF /zigman2/quotes/206189322/composite IBB +0.27% has slid 21.6% and the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.27% has dropped 21.2%.