Can Novavax's stock continue soaring? Novavax (NVAX -9.65%) has been a highly volatile stock in recent years, and that volatility is on full display again this month. Shares of the healthcare stock are up 200% since the start of May. Investors are feeling bullish on the stock once again as it has soared to a new 52-week high. What's behind this recent rally, and is it a reason to be optimistic about Novavax for the long haul? Deal with Sanofi sparks a turnaround On May 10, Novavax announced a co-exclusive l ...