UPDATE 1-Cubist Pharma to end development of blood loss drug

* Decision follows review of mid-stage top line results

* Says decision does not impact 2010 R&D cost

March 31 (Reuters) - Cubist Pharmaceuticals Inc CBST.O said it plans to end the development of its experimental treatment to reduce blood loss in patients undergoing cardiac surgery, after reviewing topline data from two mid-stage trials.

However, the company said this decision will not impact its 2010 research and development (R&D) expenses outlook that it gave in January. The company had forecast R&D expenses of $170 million to $180 million for 2010.

Cubist, which licensed the drug, ecallantide, from Dyax Corp DYAX.O, said it intends to terminate its 2008 agreement with Dyax.

In December, Cubist said it suspended enrollment in two mid-stage trials of the drug after certain data from one trial showed a higher rate of death. [ID:nBNG413023]

Shares of the company closed at $22.54 Wednesday on Nasdaq. (Reporting by Krishnakali Sengupta in Bangalore; Editing by Anne Pallivathuckal)