PO:07:096 | Safety of filgotinib in the treatment of rheumatoid arthritis: results from the multicentre SOFIA study

Anna Giorgia Osele¹, Matteo Filippini², Eugenio Capparelli³, Eleonora Bruschi⁴, Bernd Raffeiner⁵, Silvano Bettio⁶, Mariangela Salvato¹, Federico Arru⁷, Massimiliano Limonta⁴, Paola Faggioli³, Elda Piovani², Eleonora Zaccara³, Alessandro Giollo¹, Margherita Zen¹ | ¹UOC Reumatologia, Azienda Ospedale-Università di Padova; ²UO Reumatologia e Immunologia Clinica, ASST Spedali Civili, Brescia; ³UOC Ruematologia, ASST Ovest Milanese, Legnano ^MI; ⁴SSD Reumatologia, ASST Papa Giovanni XXIII, Bergamo; ⁵Dipartimento di Reumatologia, Ospedale di Formazione Paracelsus ^ASDAA-SABES, Bolzano; ⁶Medicina Generale Unità 1^, Centro Regionale per le Malattie Rare Immunologiche e Reumatologiche, Ospedale Universitario Treviso; ⁷UO Medicina, ASL 3 Nuoro, Italy

Background. To evaluate safety of filgotinib in terms of frequency, severity, and type of adverse events (AEs) and to identify predictors of AEs in a multicentre cohort of patients with rheumatoid arthritis (RA).

Materials and Methods. This is a prospective multicentre study that included patients with RA (ACR/EULAR 2010 criteria) treated with filgotinib in six different Italian centres. At follow-up visits, conducted every 3-6 months, AEs were recorded and classified as attributable to drug use with almost certain/high/low/no probability according to clinical judgement. AEs were described as severe in accordance with the EMA definition. Possible risk factors for AEs were examined using the t-test, chi-square test or Fisher's exact test as appropriate. The analysis was performed using SPSS version 29.

Results. A total of 190 patients with RA were enrolled, with a mean age of 59±11 years and a mean disease duration of 17±10 years. The mean baseline Charlson Comorbidity Index (CCI) was 2±1 (Table 1). Out of 463 follow-up visits, 128 AEs and one death were recorded, the latter considered unlikely to be associated with filgotinib use (Table 2). The most frequent AEs were infections (53 events), only 5 of which were classified as severe (9.5%). We recorded 18 AEs attributable to cardiovascular risk, all of which were considered mild except for one serious cardiovascular event, which was judged unlikely to be drug-related (Table 2). Overall, in 8% of cases, AE was considered almost certainly associated with the use of the drug, while in 27% of cases, the association was denied (Table 2). AEs caused discontinuation of therapy in 14 cases (7.3% of patients). The only factor associated with AEs that emerged at multiple time points was male gender (6 months p=0.04, 12 months p=0.02, 24 months p=0.04). Besides, a lower baseline CCI was associated with a significant reduction in AEs at 24 months (p<0.001).

Conclusions. In a large cohort of patients with RA, non-severe infections were the most frequent AE. No clinical or therapeutic risk factors (e.g., concomitant use of csDMARDs, steroid dose) associated with AEs emerged. As expected, the presence of comorbidities, assessed using the CCI, was associated with an increased risk of AEs in the long term.