Janssen Biotech Inc. sought U.S. FDA approval to expand Simponi Aria's coverage as a treatment for active psoriatic arthritis and active ankylosing spondylitis.

The Johnson & Johnson unit filed two supplemental biologics license applications for the drug, which is already approved as a therapy for adult patients with moderate to severe active rheumatoid arthritis.

Psoriatic arthritis and ankylosing spondylitis affect more than 2 million Americans, Johnson & Johnson noted in a news release.

Arthritis is any disorder that affects joints. Ankylosing spondylitis is a form of arthritis.