Prothena downgraded to Hold from Buy at Jefferies

Jefferies downgraded Prothena (PRTA) to Hold from Buy with a price target of $6, down from $32. The company’s Phase III study in light-chain amyloidosis failed for the second time, the analyst tells investors in a research note. The firm says the company will discontinue and reduce opex related to birtamimab and will have more updates in June. The next investor focus will be on PRX-012 Phase I/II for Alzheimer’s data by August, but Jefferies is cautious this will show significant efficacy.