Cancer risk with biologic and targeted synthetic DMARDs in patients with rheumatic diseases and previous malignancies: Results from the BIOBADASER register

Objective: to investigate the occurrence and relative risk of incident malignancy in patients with rheumatic diseases and previous malignancies treated with biologic and targeted synthetic DMARDs (b/tsDMARDs).Methods: Cohort study of patients included in BIOBADASER 3.0 up to 2021, treated with b/tsDMARDs and history of a previous malignancy. Incident cancer was defined as any cancer (new primary, local recurrence or metastases) during the drug exposure. Incidence rate ratios of cancer per 1,000 patients-year (PY) and 95 % confidence interval (CI) were estimated. Rates of incident cancer in tsDMARDs and other bDMARDs versus TNFi were compared.Results: A total of 352 patients from over 9,129 patients recorded in BIOBADASER 3.0 had a history of a previous malignancy. Overall, there were 47 incident malignancies (28 solid cancers, 18 non-melanoma skin cancers and 1 melanoma). The overall rate of incident malignancy was 47.4 (95 % CI 35.6-63.1) events/1,000 PY, ranging between 24.5 events/1000 PY in the anti-CD20 group to 93 events/1000 PY in the anti-CTLA-4 group. We did not find differences in the adjusted rate of incident cancer in patients exposed to JAKi [0.5 (95 % CI 0.2-1.7)], antiCD20 [0.4(95 % CI 0.1-1)], or anti-IL6 [1.1(95 % CI 0.5-2.4)], anti-CTLA-4 [1.5 (95 % CI 0.7-3.1) or anti-IL17 [0.7 (95 % CI 0.2-2.4) versus TNFi therapy.Conclusions: We did not find differences in the risk of incident cancer in patients with rheumatic diseases and a previous malignancy between TNFi and other b/tsDMARDs. While incident cancers in our cohort were limited, our data is reassuring, awaiting validation in future studies.