Prothena to lay off more than half its staff as part of reorganization

Shares of Prothena Corp. PLC shed 2.2% in premarket trade Thursday, after the biotechnology company said it would lay off about 57% of its workforce as part of a reorganization resulting from the discontinuation of its NEOD001 monoclonal antibody program. Following the reorganization, the company expects to have 63 employees. The company said the reorganization will align its resources on advancing its neuroscience platform. The stock has plummeted 61.8% year to date through Wednesday, while the iShares Nasdaq Biotechnology ETF has edged up 0.5% and the S&P 500 has gained 2.2%.