Shareholders in the rapidly growing Regeneron Pharmaceuticals (REGN -1.69%) can certainly see a little clearer now after the company reported robust top- and bottom-line growth in the fourth quarter before the opening bell today.

For the quarter, Regeneron reported a 47% increase in total revenue to $610 million as adjusted net income jumped 51% to $259 million from $171 million in the year-ago period. On an adjusted basis, that works out to $2.24 per diluted share in EPS.

The big story, of course, is the company's wet age-related macular degeneration drug Eylea, which earned blockbuster status this year, hitting $1.41 billion in U.S. sales and $402 million in net product sales this quarter within the U.S. Sales of Eylea outside the U.S., where partner Bayer (BAYR.Y -0.14%) holds licensing rights, hit $184 million. Comparatively speaking, Eylea sales within the U.S. were just $276 million during the fourth quarter last year and a mere $19 million outside the U.S. This rest-of-the-world figure is important for Regeneron as it helped the company earn an additional net profit of $44 million during the quarter.

Collaborative revenue and milestone payments were another key source of growth for Regeneron. During the quarter, collaborative revenue increased 55% to $197 million primarily due to the commercialization of Eylea outside the U.S., and because of a $25 million milestone payment received from Bayer.

Regeneron isn't content sitting on its hands, either. Because of Eylea's commercial rollout and its churning pipeline of products Regeneron's research and development expenses rose to $268 million in the fourth quarter from just $181 million last year at this time. Similarly, selling, general, and administrative expenses also rose substantially to $82 million from $58 million year over year.

Looking ahead, Regeneron anticipates net Eylea product sales of $1.7 billion-$1.8 billion in 2014, representing 24% growth at the midpoint, with $350 million-$425 million projected in capital expenditures and $425 million-$475 million in adjusted, unreimbursed R&D expenses.