Spark Therapeutics Inc. hit a $1.2 billion valuation on the biotechnology firm’s first day on the market, reflecting growing investor enthusiasm for the once-beleaguered field of gene therapy, a field that has produced the first $1 million drug.
Shares of Spark jumped to close at $50 in New York Friday after pricing at $23, becoming the latest stock to benefit from the industry’s growing momentum. Shares of Bluebird Bio Inc. have risen fivefold since a June 2013 IPO, while Avalanche Biotechnologies Inc. shares climbed from $17 at its stock-market debut in July to $60 in January, when the company announced a secondary offering.
