TOPLINE:
Treatment of patients with rheumatoid arthritis (RA) with non-tumor necrosis factor inhibitor (TNFi) biologic disease-modifying antirheumatic drugs (bDMARDs) may not pose an increased risk for cancer, compared with TNFis and conventional synthetic DMARDs.
METHODOLOGY:
- Previous research has presented conflicting results on the association between non-TNFi bDMARDs and the risk for cancer, with abatacept drawing particular attention owing to its mode of action.
- By utilizing information from Danish registers (January 2006-December 2020), researchers compared the risk for cancer in 14,944 patients with RA (age > 18 years) who were initiated on non-TNFi bDMARDs (tocilizumab/sarilumab, abatacept, or rituximab), TNFis, or were in the conventional synthetic DMARDs (bDMARD-naive) group.
- The patient population contributed to 21,982 treatment initiations, which corresponded to 1457, 1016, 690, 7458, and 11,361 treatment initiations for the tocilizumab/sarilumab, abatacept, rituximab, TNFi, and bDMARD-naive groups, respectively.
- Patients were followed up until a diagnosis was obtained for cancer, death, emigration, the initiation of a different bDMARD or a targeted synthetic DMARD, or the end of the study, whichever was earlier.
- The primary outcome was defined as any primary cancer diagnosis (except nonmelanoma skin cancer).
TAKEAWAY:
- The risk for overall cancer was not significantly higher in the tocilizumab/sarilumab-, abatacept-, or rituximab-initiated groups than in the TNFi-treated and bDMARD-naive groups.
- The likelihood of cancer appeared to be higher in patients with more than 5 years of exposure to abatacept than in the TNFi-treated (hazard ratio [HR], 1.41; 95% CI, 0.60-2.60) and bDMARD-naive groups (HR, 1.14; 95% CI, 0.51-2.33). However, the results were not statistically significant.
- Treatment with rituximab may be associated with a lower risk for hematologic cancers than for TNFi-treated (HR, 0.09; 95% CI, 0.00-2.06) or bDMARD-naive groups (HR, 0.13; 95% CI, 0.00-1.89), although the findings did not show statistical significance.
IN PRACTICE:
The authors wrote, "bDMARD-associated cancer risk remains a clinically important research question, and more future studies specifically investigating non-TNFi bDMARDs in terms of cancer risk in patients with RA are warranted."
SOURCE:
The investigation, led by Rasmus Westermann, MD, of Aalborg University Hospital, Aalborg, Denmark, was published online on March 7 in Rheumatology.
LIMITATIONS:
Many patients received more than one type of non-TNFi bDMARD treatment during the study. Because the temporal relationship of DMARD treatment with cancer was not certain, potential carcinogenic treatment effects could not be distinguished. Limited data were available on cancer risk factors.
DISCLOSURES:
The study was supported by the Danish Rheumatism Association and the Danish Cancer Society. Some authors reported financial relationships with pharmaceutical companies outside of the submitted work.