New data show that up to 70 percent of lupus patients may be able to stop immunosuppressant therapy without risking a flare-up.

The majority of lupus patients who are in clinical remission can safely stop taking immunosuppressant drugs without triggering a flare-up of their disease, according to a new study by University of Toronto researchers.

Their study provides doctors with guidance about which patients may benefit from stopping drug therapy, while reducing the risk of a relapse.

“Until now, information on whether and how immunosuppressant therapy might be stopped in lupus patients after achieving low disease activity or remission has been limited,” said lead author Dr. Zahi Touma, an assistant professor of medicine at the University of Toronto, in a press release.

Doctors sometimes prescribe immunosuppressant drugs to treat serious cases of lupus, a chronic inflammatory disease, but those medications carry potential side effects, including an increased risk of infection and cancer.

Stopping treatment can reduce those side effects, but may trigger a flare-up of lupus symptoms, such as fatigue, rashes, painful and swollen joints, and fever.

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In the study of 1,678 lupus patients from the University of Toronto Lupus Clinic who were in remission at the start of the study, researchers found that certain patients fared better after they stopped taking their immunosuppressant medication.

“For example, patients who discontinued their immunosuppressant more slowly were less likely to flare within two years,” Touma said. “Those lupus patients who were serologically active at the time the immunosuppressant was stopped were much more likely to flare on follow-up visits.”

Seventy percent of patients had no relapse within two years of stopping the immunosuppressant medication. Within three years, 50 percent still had not relapsed, and that number remained stable until the end of the 5-year study period.

In patients who flared within two years, 68 percent had a positive serology test when they stopped treatment—meaning that they had lupus antibodies in their bloodstreams—compared to 42 percent in those who didn’t flare during that time. This could serve as an indicator of which patients might benefit from stopping treatment.

In addition, patients who didn’t flare during the first two years tended to have tapered off their medication more slowly, taking on average 1.8 years to stop completely, compared to 0.9 years in the group that did experience a relapse during that time.

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According to the Centers for Disease Control and Prevention, estimates of the number of new cases of systemic lupus erythematosus, or SLE, per year range from 1.8 to 7.6 per 100,000 people. Women are six to 10 times more likely than men to be affected. In addition, blacks are more likely to develop lupus than whites.

People with lupus can cycle through periods of flare-ups and remission. They may also develop serious or life-threatening problems, such as inflammation of the kidneys, lung or heart problems, or central nervous system symptoms. These problems are more likely to require aggressive treatment with immunosuppressants, as well as high-dose corticosteroids.

The new study was presented June 11 at the European League Against Rheumatism Annual Congress (EULAR 2014), but has yet to be published in a peer-reviewed journal, so the results should be considered preliminary.

Still, the current study provides much-needed guidance for doctors about how to navigate the fine line between minimizing the side effects of immunosuppressant drugs and risking a lupus flare-up.

“This study is a milestone in lupus treatment. We know how to start medications, but only a few studies have addressed how and when to stop,” Dr. Ulf Müller-Ladner, chair of the department of rheumatology at the Justus Liebig University Giessen in Germany, told Medscape.

“The key messages are that we can stop, but we have to be careful. Not every patient can stop, and we have to know who the candidates [for stopping] are,” he added. “Patients should be closely monitored after they stop immunosuppressant therapy.”

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