Pfizer says the Food and Drug Administration approved its rheumatoid arthritis pill Xeljanz, seen as potential big seller for the company.

Pfizer Inc. says the FDA approved Xeljanz as a treatment for moderate to severe rheumatoid arthritis in patients who can't take methotrexate or haven't been helped by it. Xeljanz is intended to slow the progression of the disease. The approval comes about two weeks sooner than expected.

Xeljanz, or tofacitinib, is the first rheumatoid arthritis treatment from a new class of pain medications called JAK inhibitors. The drugs interfere with enzymes that contribute to tissue inflammation.

- Associated Press