UPDATE 1-Keryx cancer drug gets orphan drug status; shares soar

* Says multiple myeloma drug gets orphan drug status

* Says late-stage trial to start by year-end

* Keryx shares up as much as 72 pct * Shares of Aeterna Zentaris up as much as 36 pct Sept 16 (Reuters) - Keryx Biopharmaceuticals Inc (KERX.O) said its experimental cancer drug, KRX-0401, received orphan drug designation from U.S. health regulators, sending its shares up to a new 52-week high.

Keryx shares touched a high of $2.63, making them one of the top percentage gainers on Nasdaq, while shares of its Canadian partner Aeterna Zentaris Inc (AEZS.O) (AEZ.TO) reached a high of C$1.52 on the Toronto Stock Exchange.

The U.S. Food and Drug Administration's orphan drug status is reserved for new therapies that are being developed to treat diseases or conditions that affect fewer than 200,000 people in the United States and grants the drug developers seven years of market exclusivity.

"The disease (multiple myeloma) based on available clinical data is absolutely the most attractive target market for that drug," Douglas Loe, an analyst at Versant Partners in Toronto said.

KRX-0401, which is being tested as a treatment for a type of cancer called multiple myeloma affecting the plasma cells in blood, was in-licensed by Keryx from Aeterna in the United States, Canada and Mexico, while Aeterna retains rights for the rest of the world.

Keryx expects the late-stage study of the drug, also called perifosine, to start by the end of the year.

Shares of Keryx were trading up 78 cents at $2.34, while shares of partner Aeterna were up 25 percent at C$1.40 on the Toronto Stock Exchange. (Reporting by Vidya L Nathan in Bangalore, with additional reporting by Scott Anderson in Toronto; Editing by Aradhana Aravindan)