Stable Safety Outcomes with Abatacept Save

The safety of abatacept was studied using patients with rheumatoid arthritis (RA) from 7 European registers, revealing safety signals on par with that previously reported with no new safety concerns. 

This post-marketing study estimated the incidence of infections and malignancy in RA treated with intravenous or subcutaneous abatacept (ABA). Registry data included patients from ATTRA (Czech), DANBIO (Danish), ROB-FIN (Finland), ORA (France), GISEA (Italy), BIOBADASER (Spain), and SCQM (Swiss).  Abatacept exposure was measured in patient-years (p-y). Incidence rates (IRs) were calculated as the number of events per 1000 p-y of follow-up with 95% confidence intervals.

Of the over 5000 RA patients treated with ABA, most (78–85%) were female, with a mean age range was 52–58 years.

Overall the incidence rate (IR) for infections requiring hospitalization ranged from 4 to 100 events per 1000 p-y, with the highest rates reported by the DANBIO registry IR of 100 per 1000 p-y. The lowest IRs was seen in the SCQM (4 per 1000 p-y) and ATTRA (6 per 1000 p-y) registries. 

Opportunistic (OI) and tuberculosis (TB) infections were rare (IRs ranged from 0 to 14 per 1000 p-y). In BIOBADASER there were 8 OI events in 350 patients with 578 p-y of exposure. In DANBIO, there were 2 OI cases in 1213 patients with 2233 p-y of exposure. There were no opportunistic infections reported in the ATTRA registry.

The TB risk ranged from 0 to 6 per 1000 p-y with the number of events ranging from 0 in the ROB-FIN and BIOBADASER registries to 5 in the ATTRA registry .

Overall, the malignancy rate was low with ABA, ranging from 3 to 19 per 1000 p-y. The highest rates were observed in the DANBIO registry with an IR of 19 per 1000 p-y, corresponding to 70 events in 1213 patients with 3642 p-y of exposure.

These registries have heterogeneity, yet the safety profile of abatacept largely consistent with previous findings in RA, with no new or increased risks of infection or malignancy.