Stelara, in a family of medicines known as monoclonal antibodies, works by reducing certain substances in the body that can cause inflammation. The drug has been on the market since 2009 and was previously approved for the treatment of plaque psoriasis, an itchy skin condition; Crohn’s disease, a chronic digestive disorder; and a variety of rheumatological disorders. The new approved use for Stelara was based on results of a pivotal clinical trial published September 26, 2019, in the New England Journal of Medicine that found Stelara could induce and maintain remission in adults with moderately to severely active ulcerative colitis (UC). “Patients with moderate to severe ulcerative colitis typically have symptoms of rectal bleeding, diarrhea, and urgency [the need to rush to the toilet with the urge to have a bowel movement],” says William J. Sandborn, MD, a coauthor of the paper, a professor of medicine, and the chief of the division of gastroenterology at the University of California in San Diego. “If colonoscopy and biopsy is performed, you see a raw and bleeding colon wall lining [called the mucosa] and often ulcers, and the pathologist will see microscopic changes of increased immune cells,” Dr. Sandborn says. “Treatment with Stelara will often result in improvement or resolution of the patient symptoms of bloody diarrhea and urgency, and if you repeat colonoscopy and biopsy there will often be improvement or healing of both the colonoscopy and the pathology findings, so-called mucosal healing.” UC is a serious chronic and progressive inflammatory disease of the large intestine, or colon, affecting approximately 910,000 people in the United States, according to Janssen Pharmaceutical Companies of Johnson & Johnson, Stelara’s manufacturer. Stelara is the first approved biologic therapy for ulcerative colitis to target two specific substances released by immune cells that are involved in inflammatory and immune responses: the interleukin (IL)-12 and IL-23 cytokines, according to Janssen. The clinical trial pivotal for Stelara’s approval in ulcerative colitis included a total of 961 patients who were randomly assigned to receive the drug or a placebo. In the initial eight-week stage of this trial, participants received one intravenous infusion of the drug or placebo. Eight weeks later, 19 percent of patients on Stelara achieved remission of ulcerative colitis and 58 percent reported a clinical response, meaning an improvement in symptoms. Additionally, 17 percent of patients on Stelara experienced mucosal healing in the intestinal lining. For the second stage of the trial, lasting 44 weeks, participants received an injection every eight weeks. By the end of this stage, 45 percent of patients taking Stelara achieved remission, and 44 percent had mucosal healing confirmed by colonoscopy exams. One limitation of the study is that it didn’t assess the connection between mucosal improvement and long-term outcomes for patients with ulcerative colitis. There were two deaths and seven cases of cancer among 825 patients who received Stelara, compared with no fatalities and one case of cancer among 319 patients who received a placebo. “The safety of Stelara is well established, and there really are no unanswered questions about that,” Sandborn says. “The major questions about the efficacy of Stelara relate to its relative efficacy compared to the other alternative medications.” Other biologics that attack inflammation and are used to treat ulcerative colitis include Remicade (infliximab), Humira (adalimumab), and Entyvio (vedolizumab), Sandborn says. Remicade and Humira have a risk of infection and cancer that isn’t seen with Stelara, Sandborn adds. Entyvio appears safe but doesn’t always work in patients who try Remicade or Humira first. Patients may also treat flare-ups in the digestive tract with drugs known as aminosalicylates or with corticosteroids. Some patients may also take anti-diarrheal drugs to address one of the more bothersome symptoms of ulcerative colitis.