In a volatile day of trading, Millennium Pharmaceuticals ( MLNM) shares rose 7.6% after the company announced it had halved losses in the second quarter, shaking off a warning that sales of a heart drug were likely to fall.

Millennium announced second-quarter net losses on a GAAP basis of $53.9 million, or 18 cents a share, approximately half the loss of $107.1 million, or 36 cents a share, it had a year ago. On a non GAAP basis, excluding a number of items, the company said it lost $20.3 million, or 7 cents a share, narrower than Wall Street's 10-cent loss estimate and the year-ago loss of $21.7 million, or 7 cents a share.

Shortly after results were announced, the company's shares hit $9.88, a 15-month low, before reversing direction on strong volume. Shares were lately up 80 cents, or 7.6%, to $11.30, on 3.1 million shares traded, about to eclipse its average daily trading volume of 3.6 million shares, less than two hours into the trading session.

Total revenue came in at $145.3 million, topping the $134.9 million expected by analysts and up 19.4% from the $121.7 million it had a year ago. Millennium said revenue growth was due primarily to U.S. net product sales of Velcade, a treatment for multiple myeloma, which came in at $35 million, more than quadruple the year-ago quarter.

The rise in Velcade offset lower sales of the heart drug Integrilin, which it produces in conjunction with partner Schering-Plough ( SGP). The company said Integrilin generated $48.7 million in co-promotion revenue, down from $53.2 million a year ago, while U.S. ex-factory sales of the drug fell to $71.6 million from $86.7 million.

Going forward, Millennium reaffirmed earlier guidance that U.S. net product sales of Velcade would come in between $140 million and $160 million during fiscal 2004. But the company warned that U.S. ex-factory sales of Intergrilin would not come in between $320 million and $340 million, citing a gap between ex-factory sales and demand sales.

"Because Schering-Plough manages product distribution, the company has limited insight into the forces driving this gap, and we are unable to provide a new guidance range at this time," said the company, in a statement.

All told, Millennium confirmed guidance and said it expects to lose between $255 million and $285 million on a GAAP basis in fiscal 2004, with a non-GAAP loss between $175 million and $200 million.

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