ZURICH (Reuters) - Swiss drugmaker Roche Holding AG is no longer selling its acne drug Accutane as it has reached the end of its life cycle and is losing ground to generic alternatives, a spokeswoman for the group said on Friday.

Generics have been available since 2002, the spokeswoman said, adding that Accutane was introduced in 1982.

"As always when you have generics around your market share drops. This was an economical decision driven by falling market share," she said. Accutane's market share was between 4 and 5 percent.

The move was unlikely to have any impact on Roche's earnings, she said.

The last date for distribution in the United States was June 25. Accutane is now no longer available from Roche directly but patients may still be able to get it from pharmacies, she said.

By 1449 GMT, shares in the group were trading 1.5 percent higher, outperforming a 1.3 percent drop in the DJ Stoxx European pharmaceuticals sector.