Biohaven Pharmaceutical Holding Co. has rapidly transformed from one of biotech’s darlings into a cautionary tale of overheated M&A hype.
Shares of the developer of migraine treatments surged in April after Bloomberg News reported that the company was considering a sale; the stock then took another leg up earlier this month when Biohaven canceled plans to attend a Goldman Sachs health-care conference, fueling speculation a takeover was imminent. All those gains evaporated this week when the company instead announced that it was selling more shares, something that wouldn’t happen if a deal was in sight. As of midday Tuesday, the stock was down 35 percent from its highs:
