Cytokinetics Inc (CYTK.O) said its experimental drug for the treatment of a neurodegenerative disease received orphan drug status from U.S. health regulators, sending its shares up 5 percent in premarket trade.

The company recently announced data from early-stage trials of the drug CK-2017357, which is being developed for the treatment of amyotrophic lateral sclerosis (ALS), commonly known as Lou Gehrig's disease.

Lou Gehrig's disease is caused by the degeneration of motor neurons.

Cytokinetics plans to start a mid-stage evidence trial for the drug in ALS patients in the first half of 2010, it said in a statement.

Orphan drug designation is granted by the U.S. Food and Drug Administration (FDA) to drugs or biologics that treat a condition affecting less than 200,000 Americans.

The status grants the drugmaker a marketing exclusivity of seven years in the United States, upon approval.

Shares of the company were up about 5 percent at $3.50 in premarket trade. They closed at $3.33 Tuesday on Nasdaq.