Biotech company Millennium Pharmaceuticals Inc. has successfully raised $250 million to help fuel potential acquisitions and general corporate activity.

The Cambridge, Mass. company (Nasdaq MLNM) raised the amount by selling convertible senior notes due Nov. 15, 2011. Morgan Stanley & Co. Inc. and J.P. Morgan Securities Inc. acted as joint book-running managers.

It's not as if Millennium needs the cash. The company reported more than $635 million in cash and equivalents on hand as of Sept. 30. But the move to raise more funds comes after Millennium lost a bid to buy cancer drug developer AnorMed Inc. earlier this fall.

After a fierce bidding war, biotech giant Genzyme Corp. in Cambridge won out, agreeing to pay $580 million for the Canadian company. Millennium had bid $515 million, which trumped an earlier Genzyme bid.

Millennium announced in late October that it would lay-off 150 employees, outsource some drug discovery functions and consolidate space in Cambridge.