The company plans to evaluate its next steps for briakinumab, including resubmission at a later date, Abbott said in a securities filing on Friday. An Abbott spokeswoman declined to comment further on the regulators' concerns.

Abbott released results last October of a 52-week study of 317 patients with moderate to severe psoriasis that showed the drug was significantly better than methotrexate in its ability to clear the unsightly, scaly and often painful skin patches associated with plaque psoriasis -- a disease of the immune system.

Briakinumab is a biotechnology drug that targets proteins that have been linked to inflammation called IL-12/23. It is in the same class as Johnson & Johnson's Stelara.

Abbott submitted its applications to Europe and U.S. regulators late last summer.

Analysts have been expecting briakinumab sales to reach $375 million in 2014, according to consensus expectations provided by Thomson Reuters Pharma.

Abbott's huge-selling drug, Humira, is approved to treat psoriasis, among other immune system disorders.

Abbott shares slipped 12 cents, or 0.3 percent, to $47.25 in morning trading on the New York Stock Exchange.