What happened

The stock performance of BioMarin (BMRN 0.97%) was less than healthy on Thursday. Shares of the biotech, which specializes in treatments for rare diseases, fell by more than 6% after management delivered an earnings release that did not please investors.

So what

After the close of trading Wednesday, BioMarin unveiled its results for the fourth quarter and full year. The company's revenue slipped by 1% in the quarter to just under $450 million. The change was more dramatic on the bottom line, where the biotech flipped to a nearly $58 million ($0.32 per share) GAAP loss, compared to the more than $22 million profit it earned in Q4 2020.

Woman in a lab looking through a microscope.

Image source: Getty Images.

The bottom-line deficit matched the average estimate among analysts, while the revenue figure was a bit higher than the consensus $442 million expectation. 

Last year was a period of adjustment for BioMarin following the October 2020 expiration of patent protection for its phenylketonuria (PKU) drug Kuvan, a major source of revenue. On the other hand, in late 2021, the company won marketing approval for its achondroplasia drug, Voxzogo, from both European Union and U.S. regulators.

More recently, the company's leading pipeline candidate BMN 270 -- being tested as a treatment for severe hemophilia A -- met all primary and secondary efficacy endpoints in a phase 3 clinical trial.

Now what

BioMarin's guidance for 2022 is that it will book revenue in the $2.05 billion to $2.15 billion range, and deliver a GAAP profit of $95 million to $135 million. According to data compiled by Yahoo! Finance, the average analyst estimate for 2022's annual revenue is $2.14 billion.