Ultragenyx Pharmaceuticals discontinues Ace-ER development By: MarketMinute.com Stock News August 23, 2017 at 18:48 PM EDT Ultragenyx Pharmaceutical Inc. (Nasdaq: RARE) will discontinue clinical development of Ace-ER after disappointing Phase 3 study results. The stock price plunged $7.83 to close at $51.02. Related Stocks: Ultragenyx Pharmaceu