Prothena (NASDAQ:PRTA – Get Free Report) had its target price lowered by JMP Securities from $83.00 to $81.00 in a research note issued on Friday, Benzinga reports. The brokerage presently has a “market outperform” rating on the biotechnology company’s stock. JMP Securities’ price target indicates a potential upside of 115.71% from the stock’s previous close. […]