Rheumatoid arthritis patients treated with biological drugs against the immune factor TNF are not at greater risk of developing lymphoma than peers treated with other medications, according to a study from the University of Manchester.
The study, “Risk of lymphoma in patients exposed to antitumour necrosis factor therapy: results from the British Society for Rheumatology Biologics Register for Rheumatoid Arthritis,” published in the journal Annals of the Rheumatic Diseases, further suggests that larger studies with longer follow-up times are needed to exclude possibilities that long-term exposure might put patients at increased risk of lymphoma.
Risk for lymphoma among patients with rheumatoid arthritis is a well-known fact. Since the advent of biological drugs to manage the crippling condition, scientists have raised concern that the main group of biological medications that block the immune factor TNF might further contribute to the risk.
The U.S. Food and Drug Administration (FDA) demands that a black box warning draw user attention to the risk. The FDA also warns that the drugs might increase risk for the rare and aggressive hepatosplenic T-cell lymphoma in children and adolescents.
In an attempt to get a clearer picture of the matter, researchers looked at the British Society for Rheumatology Rheumatoid Arthritis Register (BSRBR-RA) to study data on thousands of patients.
The study recruited patients who had not been using TNF blockers or other biological drugs before study start. Researchers followed 11,931 patients treated with TNF-blocking drugs and 3,367 patients who had never used biological medications over time. The register was established in 2001, and the study monitored patients until they developed lymphoma, died, or until the end of the study November 30, 2013.
Patients were examined using standard tools to assess severity of arthritis, and underwent other health examinations and questionnaires to gather information on disease duration, drug use, the presence of other diseases, and smoking history.
Since TNF blockers are reserved for patients with more disease activity, it was no surprise to find that the group using the drugs had more symptoms, and had been sick for longer than patients who never used biological drugs.
After taking into account a range of factors that could affect the outcome of the analysis, researchers showed that patients treated with TNF blockers had the same risk of developing lymphoma as those who used other disease modifying drugs. The study concluded that treatments, at least up to five years, do not increase risk for lymphoma in rheumatoid arthritis patients.