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May 22 (Reuters) - Lantheus Holdings LNTH.O is weighing a potential sale after getting a takeover offer from private-equity backed Curium Pharma that values it at about $7 billion, Bloomberg News reported on Friday, citing people familiar with the matter.

The two companies have been in discussions about a potential deal that could be weeks away, the report said, adding that no final decision has been made and there is no guarantee the talks will result in a transaction.

Curium was valued at about $7 billion last year when its owner, CapVest Partners, raised funds for a continuation vehicle for the nuclear medicine company, the report said.

Lantheus and Curium did not immediately respond to Reuters' request for comment.

Shares of the radiopharmaceutical-focused company were trading down nearly 2% in extended trading. They have gained 54.8% so far this year, giving the company a market capitalization of about $6.15 billion.