Biopharma giant MedImmune (NASDAQ:MEDI) announced preliminary first-quarter financial results yesterday. As a general rule, most drug companies exhibit some seasonality to their top and bottom lines, since wholesalers who buy their products generally stock up on more drugs in the fourth quarter. Some drugmakers, though, including MedImmune, derive most of their revenue in certain seasons, since their products are used to treat primarily winter-based ailments such as the flu.

Last year, 87% of MedImmune's sales came from the respiratory infection drug Synagis. Synagis sales are expected to only grow 9%-10% this quarter, but with the magic of revenue growth scaling at a faster pace than expenditures, MedImmune will be able to grow earnings to a much greater degree than its top line.

For the first quarter, MedImmune expects earnings per share to nearly triple versus last year, to $0.62 a share. It also predicts full-year earnings of $0.90 to $0.95 a share, also roughly three times higher than in 2006. The impetus for this year's expected earnings growth: dramatically lower R&D and SG&A spending as a percentage of sales in 2007.

As long as MedImmune keeps costs in check, it should have no problem meeting its 2009 goal of $2 billion in revenue, nor its $2 target for diluted earnings per share. Besides moderate top-line growth with Synagis, MedImmune wins no matter which drug prevails in the multibillion-dollar human papillomavirus (HPV) vaccine race between Merck (NYSE:MRK) and GlaxoSmithKline (NYSE:GSK), since it will receive royalties on both vaccines.

Fool contributor Brian Lawler does not own shares of any company mentioned in this article. GlaxoSmithKline is an Income Investor recommendation. The Fool has a disclosure policy.