Altimmune Inc (NASDAQ:ALT) shares are trading higher Monday despite a lack of company-specific news. The stock has experienced elevated levels of volatility in recent months. Here’s a look at what’s going on. What To Know: Altimmune reported positive results in early December showing that patients taking a dose of its pemvidutide lost 15.6% of their total weight after 48 weeks. Shares soared following the update from the company. Earlier this month, Kerrisdale Capital announced a short position in the stock, claiming the company had little chance of competing against others in the GLP-1 space …