Detection and evaluation of a drug safety signal concerning pancreatic cancer: lessons from a joint approach of three European biologics registers

Methods. Patients with enrolled in the British Society of Rheumatology Biologics Register (BSRBR), the Swedish Rheumatology Register (SRR) or the German Biologics Register [Rheumatoid Arthritis Observation of Biologic Therapy (RABBIT)] were analysed. The patients were exposed to biologic or conventional DMARDs. Outcomes were obtained from physician reports, health authorities and via linkage to national cancer and death registers. Age- and gender-standardized incidence ratios (SIRs) of PCa were calculated based on the expected rates available from the individual national cancer registers. Results. Data from 5126 (Germany), 16 930 (UK) and 19 351 (Sweden) RA patients were available for the analysis. The highly discrepant prescription rates of LEF in the respective countries resulted in 11 343 (Germany), 30 787 (UK) and 2518 (S) patient-years of exposure to LEF. Compared with the general population, the incidence of PCa in patients ever exposed to LEF corresponded to a SIR of 3.1 (95% CI 1.3, 6.5) in Germany, 1.05 (95% CI 0.5, 2.1) in the UK and 1.8 (95% CI 0.1, 10.2) in Sweden. Conclusion. The results of the replication analyses do not support the hypothesis of an increased risk of PCa in patients exposed to treatment with LEF. However, they do not completely rule out concerns, and therefore further verification in other data sets is recommended.