Shares of Jasper Therapeutics Inc. /zigman2/quotes/206872721/composite JSPR -2.12% soared 106.2% in volatile morning trading, enough to pace the Nasdaq's gainers, after Oppenheimer analyst Jay Olson's bullish endorsement the day after the stock closed at a record low. The stock had been halted for volatility twice in the first half hour after the open, as trading volume swelled to 20.7 million shares. The company started trading as a biotechnology company with its "JSPR" ticker after the closing of the acquisition by special purpose acquisition company (SPAC) Amplitude Healthcare Acquisition Corp. was announced after the Sept. 24 close. From that day through Tuesday, the stock had plunged 52.3%, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -1.11% slipped 2.4% over the same time. Oppenheimer's Olson initiated Jasper with an outperform rating and stock price target of $21, implying a further 41% gain from current levels. "We view [Jasper] as an emerging leader in the development of novel targeted conditioning agents for hematopoietic stem cell transplantation (HSCT) with lead candidate JSP191 and proprietary engineered hematopoietic stem cell (eHSC) platform," Olson wrote in a note to clients.