Ultra-rare disease fighting biotech BioMarin Pharmaceutical (NASDAQ:BMRN) proved in its first-quarter results after the bell that there's certainly growth to be had in developing therapies that treat rare diseases. For the quarter, BioMarin reported a revenue jump of 18.5%, to $151.5 million, driven by product sale gains across the board.

The company's launch of Vimizim during the quarter netted $0.9 million in revenue, while Naglazyme (by far BioMarin's best-selling drug), Kuvan, Aldurazye, and Firdapse all delivered revenue gains of 15%, 20%, 8%, and 31%, respectively. Though small, even BioMarin's collaborative and royalty revenue soared to $2.5 million combined versus just $0.6 million in the prior-year period.

Operating expenses for the quarter increased nearly 11%, to $178 million, as selling, general, and administrative expenses rose 18%, tied mainly to the launch of Vimizim. Research and development expenses increased by 3%, as well.

On the heels of higher sales came a significantly smaller adjusted quarterly loss of just $1.7 million, or $0.01 per share, compared to a loss of $8 million, or $0.07 per share, in the year-ago quarter. BioMarin announced that it ended the quarter with $1.14 billion in cash and cash equivalents.

Looking forward, BioMarin left its previous revenue guidance of $650 million to $680 million unchanged; however, it did note that current sales trends would favor the upper end of its current projections. Furthermore, the company now believes that its R&D expensing of $500 million to $530 million, as well as adjusted loss of $100 million to $130 million, are trending toward the lower-end of its prior guidance.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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