UPDATE 1-EU approves Actelion's Tracleer for children

* Only drug with approved paediatric formulation

* Actelion trying to expand Tracleer use

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ZURICH, July 6 (Reuters) - European regulators approved Actelion's ATLN.VX Tracleer for the treatment of heart and lung condition pulmonary arterial hypertension (PAH) in children, the Swiss biotech group said on Monday.

Tracleer is now the only drug with an approved paediatric formulation for treating children from two years of age, Actelion said in a statement.

The company is trying to expand use of Tracleer, which already rakes in more than $1 billion a year, into new diseases and patients to reduce its dependence on its main PAH market. (Reporting by Sam Cage; editing by Simon Jessop)