UPDATE 3-FDA adds strict safety warnings on arthritis drugs from Pfizer, AbbVie and Lilly

(Adds details on Eli Lilly's drug)

Dec 3 (Reuters) - The U.S. health regulator has added its strictest warning to the labels of drugs from Pfizer, Eli Lilly and AbbVie belonging to a class of anti-inflammatory treatments called JAK inhibitors, citing risk of serious health issues and death in patients 50 and over, the drugmakers said on Friday.

The addition of the warning https://www.accessdata.fda.gov/drugsatfda_docs/label/2021/203214s031lbl.pdf on the labels follows the agency's review of Pfizer's Xeljanz after initial results from a February trial showed an increased risk of serious heart-related problems and cancer in some patients being treated with the drug.

Xeljanz, which brought in worldwide sales of $2.44 billion for Pfizer in 2020, is approved in the United States for the treatment of conditions including rheumatoid arthritis, psoriatic arthritis and ulcerative colitis - an inflammatory bowel disease.

AbbVie's rheumatoid arthritis drug Rinvoq and Pfizer's Xeljanz are now recommended for use only in patients, who have had inadequate response or intolerance to one or more TNF blockers, which are another class of drugs used against inflammatory conditions.

The Food and Drug Administration's boxed warnings on the labels of Rinvoq , Xeljanz and Lilly's Olumiant flags the risk of cardiovascular death and stroke in high-risk patients who are aged 50 and above, and are current or past smokers.

Additional information about the risk of some types of cancer and death was also added to their labels.

The marketing applications for Rinvoq's expanded use in atopic dermatitis, psoriatic arthritis, ankylosing spondylitis and ulcerative colitis remain under review by the FDA, AbbVie said. (Reporting by Manojna Maddipatla in Bengaluru; Editing by Anil D'Silva and Krishna Chandra Eluri)