What happened

Lantheus (NASDAQ:LNTH) is up 20.5% at 12:32 p.m. EDT following the company's report of first-quarter earnings after the closing bell yesterday.

So what

First-quarter revenue came in at $81.4 million. That's just 6.4% higher than the year-ago quarter, but it takes into account divestiture of some of Lantheus' products and beat management's guidance of $77 million to $80 million, which explains the higher share price. Definity, the company's ultrasound contrast agent, was the driving force behind the increased revenue, growing by 20% year over year. TechneLite, which is used in nuclear medicine diagnostic imaging tests, also had a nice quarter, up 8% year over year.

Echocardiogram

Image source: Getty Images.

On the bottom line, Lantheus' earnings per share were down year over year, but that was due to a large gain in the year-ago quarter from the sale of its Canadian radiopharmacy business and expenses in the recently completed quarter to refinance its debt and consolidate its campus. When you factor out those one-time expenses, adjusted earnings were $0.28 per diluted share, up from $0.15 per share in the year-ago quarter.

Now what

Given the strong first quarter, Lantheus' management raised its revenue guidance for the year to a range of $313 million to $318 million. That's only a $1 million increase on either side of the range compared to previous guidance, suggesting management might be sandbagging a little. Guidance for adjusted earnings before interest, taxes, depreciation, and amortization (EBITDA) was also increased to between $80 million and $83 million, up from a range of $79 million to $82 million.

Brian Orelli and The Motley Fool have no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.