A recent meta-analysis determined that patients with inflammatory bowel disease (IBD) who take Janus Kinase (JAK) inhibitors may face an increased risk of herpes zoster infection. Patients with other immune-mediated diseases may face the same increased risk as well.
The researchers investigated several JAK inhibitors’ safety profiles, including Xeljanz (tofacitinib) and Rinvoq (upadacitinib), in patients with IBD or other immune-mediated diseases such as rheumatoid arthritis. The herpes zoster infection rate ended up being 2.67 per 100 person-years. A 2005 study found that the rate of herpes zoster infection amongst the general population in the United States was 3.2 per 1,000 person-years.
“Herpes zoster and serious infections seem to be rather common among these patients,” the recent study said. “More studies with long follow-up and in the real-world setting, in the different conditions will be needed to fully elucidate the safety profile of the different JAK inhibitors.”
The recent study’s authors wrote that decisions about how to position new IBD treatments become more difficult as more and more new IBD treatments hit the market.
“With an increasing therapeutic armamentarium, treatment algorithms in IBD will become more complex, with several drug classes and many compounds within each class will become difficult to determine adequate drug positioning,” the study said. “Knowing the exact safety profile of JAK inhibitors will help to adequately weigh the risk/benefit ratio of this drug class.”
Xeljanz treats moderate to severe rheumatoid arthritis. It also treats moderate to severe ulcerative colitis and active psoriatic arthritis. JAK inhibitors work by reducing immune system activity. Rheumatoid arthritis, ulcerative colitis and psoriatic arthritis can be caused by overactive immune systems.
The U.S. Food and Drug Administration (FDA) announced in February 2019 that taking 10 mg of Xeljanz twice per day for rheumatoid arthritis can increase one’s risk of blood clots in the lungs or death. The FDA later approved a Boxed Warning for the drug in July 2019. It warned that taking Xeljanz for ulcerative colitis twice per day could increase one’s risk of blood clots and death. Blood clots can cause pulmonary embolism, pulmonary thrombosis, deep vein thrombosis or stroke.
Undesirable tissue growth in joints is responsible for rheumatoid arthritis. Pain and inflammation are caused by this tissue. The pain and inflammation worsen when the tissue is attacked by the immune system. DNA transcription drives this tissue growth. Xeljanz works by slowing down JAK enzymes which drive DNA transcription.