U.S. regulators are considering extending their approval of Pfizer’s rheumatoid arthritis therapy Xeljanz to ulcerative colitis as well.

That possibility surfaced when the Food and Drug Administration accepted Pfizer’s supplemental New Drug Application for Xeljanz (tofacitinib citrate) as a treatment for adults with moderate to severe ulcerative colitis.

The FDA requires a company to file a New Drug Application when it wants to market a new treatment in the United States.

A supplemental application is a request to use the therapy for an additional disease. It usually includes information about the therapy’s effectiveness against the other disease. That information can come from both clinical trials and preclinical-trial studies.

Pfizer included the results of three Phase 3 clinical trials of Xeljanz in its supplemental application. The company named the trials OCTAVE, for Oral Clinical Trials for tofAcitinib in ulceratiVE colitis. The three studies were called OCTAVE Induction 1, OCTAVE Induction 2 and OCTAVE Sustain.

Xeljanz eliminated ulcerative colitis in a significantly higher percentage of patients than those who received a placebo, researchers said. It also healed the intestinal linings of twice as many patients who took it by the eighth week of the OCTAVE Induction 1 trial — 31.3 percent, versus 15.6 percent of the placebo group.

The therapy inhibits Janus kinases, enzymes that promote pro-inflammatory proteins involved in the development of autoimmune diseases such as ulcerative colitis.

“Ulcerative colitis is a debilitating inflammatory disease that impacts the physical, emotional and social well-being of nearly one million people in the United States, many of whom are not able to manage their disease,” Michael Corbo, who heads Pfizer’s inflammation and immunology therapy development program, said in a press release.

“We look forward to working with the FDA as they consider the application for tofacitinib in ulcerative colitis, with the goal of offering, if approved, the first oral Janus kinase (JAK) inhibitor as a therapeutic option for people living with moderately to severely active ulcerative colitis,” he said.