A major competitor to EpiPen, the lifesaving allergy injection that has become the latest flashpoint in the debate over high drug prices, will launch on Valentine’s Day at a list price of $360 for a two-pack, the company KalA o announced on Thursday. For years, pharmaceutical company Mylan hiked the price on EpiPen — to $609 for a two-pack, enjoying a near monopoly on the growing allergy injection market.