Drug giant Merck & Co. of Whitehouse Station, N.J., said after market close Monday it has agreed to buy Sirna Therapeutics Inc. of San Francisco, a leader in the emerging field of RNA interference therapy, for $1.1 billion.
The purchase is the latest indication that RNA interference, or RNAi, is quickly maturing from revolutionary scientific discovery to potential remedy for several diseases. The cash-for-stock transaction values Sirna at $13 a share, more than double its $6.45 closing price Monday afternoon. In after-hours trading, the stock has jumped to $12.43, or 93 percent.
