THOUSAND OAKS, California (

TheStreet

) --

Amgen

(AMGN) - Get Report

could approach Swiss drugmaker

Actelion

with a takeover offer this week,

Bloomberg

reports.

Amgen, the world's biggest biotechnology company, is considering a takeover offer for Actelion to gain new medicines for rare diseases,

Bloomberg

says, citing two people with knowledge of the matter.

Actelion learned recently of a potential bid from Amgen, and in a defensive move discussed asking

Roche Holding

,

Johnson & Johnson

(JNJ) - Get Report

and

Bristol-Myers Squibb

(BMY) - Get Report

to consider taking a minority stake, the people said.

Actelion is the world's biggest maker of pulmonary arterial hypertension drugs.

An Amgen spokesman declined to comment for

Bloomberg

on the company's potential bid. Actelion, meanwhile, said in a statement Wednesday that "as part of its ordinary course of business, the company is in regular dialogue with other industry participants."

Amgen hasn't made a final decision and a formal offer may not emerge, one of the people said,

Bloomberg

reports.

-- Written by Joseph Woelfel

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Joseph Woelfel

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