UPDATE 1-Discovery Labs says lung drug unlikely to get FDA nod

* Co says prudent to focus on other development programs

* May consider appeal

* Shares halve in value

July 1 (Reuters) - Discovery Laboratories Inc (DSCO.O) said its lung drug surfaxin was not likely to get approval in the near term as the regulator has applied a newly defined standard, sending its shares down 53 percent.

Though the regulator indicated the company could consider conducting a limited clinical trial to increase the chances of gaining approval for the drug, Discovery said it was now more prudent to focus on other development programs.

In April, the U.S. Food and Drug Administration declined to approve the drug as a preventive treatment for Respiratory Distress Syndrome (RDS) in premature infants.

The company said it had believed the data it submitted subsequently to the FDA supported approval of the drug, but the regulator's application of a newly defined standard made approval unlikely.

Discovery Labs said it will determine its next course of action, including an appeal through the FDA's Formal Dispute Resolution process.

Shares of the company were trading at 49 cents after the bell. They closed at $1.05 Wednesday on Nasdaq. (Reporting by Vidya L Nathan in Bangalore; Editing by Vinu Pilakkott)