The incidence of cancer in sle patients receiving biologic therapy: results from the british isles lupus assessment group biologics registry (bilag-br)

Background/Aims Patients with systemic lupus erythematosus (SLE) are known to have an increased risk of certain cancers, such as lymphoma, compared to the general population. We aimed to characterise the incidence of cancers in patients with moderate-severe SLE receiving biologic and standard of care (SoC) therapies. Methods The BILAG Biologics Registry (BILAG-BR) is a large prospective observational register of patients with SLE. Participants receiving rituximab, belimumab and SoC therapies from 2010-2021 were included. Data relating to malignancy were collected from study centres and the UK national cancer register. Overall cancer risk was assessed using a Cox proportional hazards model in Stata V14. Results There were 114 previous cancer diagnoses in 108 patients recorded. The most common cancer sites were cervical (43/114), non-melanoma skin cancer (20), breast (15) and lymphoma (13). All cervical neoplasms were carcinoma in situ. Five patients had more than one cancer diagnosis recorded; three had >1 non-melanoma skin cancer and two individuals had unrelated malignancies. During follow-up, (1437 patients with 5,738 person years [pys]), 33 incident cancers occurred in 32 individuals at a median of 477 (IQR 218-1265) days after registration. Incidence rates were 5.9 (95% CI 3.9-8.8) in rituximab, 7.8 (2.5-24.2) in belimumab and 4.16 (1.7-10.0) per 1,000 pys in the SoC group. Using rituximab as the comparator, the age and gender adjusted hazard ratio (HR) was 1.62 (0.48-5.52) for belimumab and 0.63 (0.24-1.65) for the SoC group. Patients who developed an incident cancer were older at registration (HR 1.07 [1.04-1.09] per year) and more likely to be of male sex (HR 2.95 [1.31-6.57]). Caucasian ethnicity was associated with increased risk in univariate analysis (HR 4.25 [1.46-12.32]), but not after adjusting for age and sex (HR 2.60 [0.86-7.83]). There were 6 cancer-related deaths which all occurred in the rituximab group a median of 2.3 (IQR 1.4-3.2) years from registration. Conclusion Although overall cancer numbers are low, the findings of this study are reassuring. The incidence of cancer in this cohort of SLE patients with moderate-to-severe disease appears to be broadly similar between those on biologic and standard of care therapies. Disclosure M. Rodziewicz: Grants/research support; North West England MRC Fellowship Scheme in Clinical Pharmacology and Therapeutics. Award Ref. MR/N025989/1, UCB. S. Dyball: Grants/research support; North West England Medical Research Council Fellowship Scheme in Clinical Pharmacology and Therapeutics. Award Ref. MR/N025989/1, UCB, Eli Lilly. E. Sutton: None. B. Parker: Honoraria; Fresenius-Kabi, AbbVie. Member of speakers’ bureau; Eli Lilly, Roche. Grants/research support; Genzyme/Sanofi, GSK. I.N. Bruce: Consultancies; AstraZeneca, Eli Lilly, ILTOO, GSK, Aurinia. Member of speakers’ bureau; GSK, UCB, AstraZeneca. Grants/research support; GSK, Roche, Janssen.