* Overall survival at 12.4 months
* 53 pct patients survive at 12 months
* Shares up 4 pct premarket
Sept 29 (Reuters) - ZymoGenetics Inc ZGEN.O said its experimental skin cancer drug showed promising survival data in a mid-stage trial, sending the biotechnology firm's shares up 4 percent.
The study, conducted with recombinant Interleukin 21 (IL-21) as a single agent, showed overall survival of 12.4 months, the company said in a statement.
Zymogenetics said 53 percent of the total 40 patients enrolled in the study survived at 12 months.
Shares of the Seattle-based firm touched a 52-week high of $9.79 on Sept. 8 after Bristol-Myers Squibb Co (BMY.N) said it would acquire ZymoGenetics in a deal valued at $885 million. [ID:nN07253834]
They were trading up 4 percent at $10.15 in premarket trading Wednesday. The stock closed at $9.75 Tuesday on Nasdaq. (Reporting by Rajarshi Basu in Bangalore; Editing by Maju Samuel)