Biologics for RA Do Not Increase Malignancy Risk

When compared with traditional treatments, biologic therapies for RA were found to not be associated with an increased risk of cancer.

Some concern exists about drugs that modulate immune system activity, particularly with respect to malignancies and infections. A recent meta-analysis of pooled data from more than 60 controlled trials revealed that there is no significant risk of malignancy for patients with rheumatoid arthritis (RA) receiving biologic therapies.

The study, according to a release from MD Anderson Cancer Center, is “the largest systematic review evaluating the risk of developing any malignancy among rheumatoid arthritis patients using approved biologic response modifiers, several of which include tumor necrosis factors.” Since 2009, tumor necrosis factor (TNF) inhibitors have been required to display a warning in their prescribing information highlighting the increased risk of cancer in children and adolescents who receive these drugs to treat juvenile RA, Crohn’s disease, and other inflammatory diseases.

Investigators identified previous trials that included the biologics abatacept, adalimumab, anakinra, certolizumab, etanercept, golimumab, infliximab, rituximab, or tocilizumab. They selected trials where the patients on biologics were compared with patients taking either disease-modifying antitrheumatic drugs or placebo for 24 weeks or longer.

Of the 29,423 patients included in the study, 211 developed malignancies over the study period. Cancer occurred in all 3 treatment groups regardless of therapy type. Twenty-three of 3615 patients in the biologic monotherapy group developed cancer, whereas 123 of 15,989 patients in the biologic combination therapy group and 65 of 9819 patients in the control group developed a malignancy. The number of people developing cancer in each group was not statistically significant, according to the authors.

“Overall, our findings do not support an increased risk of malignancy for patients with RA receiving [biologic response modifiers] in [randomized controlled trials] of at least 24 weeks’ duration,” Maria A. Lopez-Olivo, MD, PhD, of the University of Texas MD Anderson Cancer Center, and colleagues wrote.

The investigators noted that the long-term risks associated with the use of biologics to treat RA are not well known, nor is the risk of cancer recurrence in RA patients with a history of cancer or cancer risk factors.

Interestingly, about half of the cancers observed by the FDA in 2009 in children prescribed TNF blockers were lymphomas, a type of cancer involving cells of the immune system. In the meta-analysis from investigators at MD Anderson Cancer Center, the risk of lymphoma was doubled among patients treated with TNF inhibitors, but the difference did not achieve statistical significance.