Shares of Regeneron were down about 3 percent after the U.S. Food and Drug Administration approved the company's cholesterol-lowering drug Praluent on Friday.
The company's stock was halted at around 2 p.m. on Friday for news pending and was down 2.62 percent when halted. Shares of the company resumed trading at 3:40 p.m. ET and have risen over 30 percent in 2015 and nearly 80 percent in the last year.
The FDA said in a release the drug is "the first cholesterol-lowering treatment approved in a new class of drugs known as proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors."
"Praluent provides another treatment option for patients with [heterozygous familial hypercholesterolemia] or with known cardiovascular disease who have not been able to lower their [low-density lipoprotein] cholesterol enough on statins," John Jenkins, director of the Office of New Drugs at the Center for Drug Evaluation and Research, said in the release.
The FDA added it approved the drug after conducting five placebo-controlled trials where 2,476 participants were exposed to Praluent.
"Participants taking Praluent had an average reduction in LDL cholesterol ranging from 36 to 59 percent, compared to placebo," the agency said.
Some of the more common side effects of the drug include itching, swelling, pain and flu, it added.