Roche has agreed to buy Spark Therapeutics for $4.8 billion, the latest strong signal that major pharmaceutical companies are ready to gamble on the promise of gene therapy despite its uncertain commercial prospects.

The Swiss pharma giant will pay $114.50 per share, in cash, for Spark (NASDAQ: ONCE), a 122 percent premium to the gene therapy developer’s $51.56 per share closing price on Friday. Both boards have approved the deal, which should close in the second quarter.

The acquisition is the latest sign of the continuing momentum for gene therapy, which has taken decades to begin to fulfill its… Read more »