Oppenheimer believes that yesterday's 9% decline in The Medicines Co is linked " to speculated safety concerns regarding approved PCSK9 mABs following posts on a message board frequented by industry drug representatives." According to anonymous posts, Amgen (AMGN), Regeneron (REGN), and the FDA are reviewing reports about cognitive or brain problems experienced by patients receiving the drug, the firm stated. Although Amgen denied that the FDA is probing safety problems related to the drug, Oppenheimer says that investors are sensing a potential problem with the drug, which significantly impacts The Medicines Co's valuation, according to the firm. Oppenheimer keeps a Perform rating on the stock.