MedImmune ( MEDI) shares were virtually unchanged on Thursday after the company announced second-quarter earnings that beat Wall Street estimates while guiding lower for the third quarter.

MedImmune, best known for its core product, the influenza vaccine FluMist, announced a second-quarter net loss of $100.3 million, or 40 cents a share, far worse than the profit of $13.5 million, or 5 cents a share, it had a year ago.

Excluding a number of charges associated with the company's termination of its collaboration with Wyeth ( WYE ) on FluMist, MedImmune lost $29 million, or 12 cents a share, beating Wall Street's 17-cent loss estimate. In response, shares were off 2 cents, or 0.1%, to $22.48.

Total revenue came in at $94 million, beating the $93 million expected by analysts, but falling 16.8% from the year-ago $113 million. The year-ago quarter included $32 million in milestone payments associated with the approval of FluMist in June 2003 and for passing $100 million in non-U.S. end-user sales for Synagis, a respiratory treatment.

Excluding milestone payments, using only product sales, MedImmune saw revenue grow. The company said product sales came in at $91 million, up 13% from last year, driven by a 10% increase in sales of Synagis. Sales of its two other products, Ethyol and CytoGam, rose 4% and 123%, respectively.

Expenses soared in the second quarter, coming in at $263 million, more than double the year-ago $103.7 million. Research and development expenses were $57 million, up from $30 million last year, because of a number of clinical trials for FluMist and other drugs in the company's pipeline.

Going forward, the company said that third-quarter revenue would range between $85 million and $90 million, below the current Wall Street consensus of $92.4 million. MedImmune said third-quarter losses, excluding charges, would range between 22 and 25 cents a share, which is also below the current Wall Street estimate of a 16-cent loss.