Background Acute anterior uveitis (‘uveitis’), or ‘iritis’, is a common extra musculoskeletal manifestation among patients (pts) with axial spondyloarthritis (axSpA). The prevalence of uveitis varies with HLA-B27 positivity, axSpA subtype and disease duration, reaching >50% in radiographic (r)-axSpA (i.e., ankylosing spondylitis) ^[1] pts with >40 years symptom duration ^[2].

Interleukin (IL)-17 has been implicated in the pathogenesis of uveitis; however, inhibition of IL-17A alone may not be optimal for the management of uveitis ^[3]. Here, we report the incidence of uveitis following inhibition of IL-17A in addition to IL‑17F with bimekizumab (BKZ).

Objectives To compare incidence rates of uveitis in pts with axSpA treated with placebo (PBO) or BKZ 160 mg every four weeks (wks; Q4W) to Wk 16 of the phase (ph)3 trials BE MOBILE 1 and 2.

To evaluate incidence rates of uveitis in pts with axSpA treated with BKZ 160 mg Q4W, using pooled ph2b/3 data.

Methods The ph3 studies BE MOBILE 1 (NCT03928704; non-r-axSpA) and 2 (NCT03928743; r‑axSpA) comprised a 16-wk double-blind treatment period (DBTP; subcutaneous BKZ 160 mg Q4W or PBO) followed by a 36‑wk maintenance period (all pts received BKZ 160 mg Q4W) ^[5]. Upon entry to the ongoing BE MOVING open-label extension (OLE; [NCT04436640; cut-off 4 Jul 2022]) at Wk 52, all pts remained on BKZ 160 mg Q4W.

The ph2b study BE AGILE (NCT02963506; r-axSpA) comprised a 12‑wk double-blind, dose-ranging period followed by a 36-wk randomised period (BKZ 160 or 320 mg Q4W) ^[4]. Upon entry to the ongoing BE AGILE OLE (NCT03355573; cut-off 4 Jul 2022) at Wk 48, all pts received BKZ 160 mg Q4W.

Data were pooled for all pts treated with BKZ 160 mg Q4W in the ph2b/3 trials listed above. Data were pooled separately for pts randomised to BKZ or PBO in the DBTP of BE MOBILE 1 and 2. Uveitis treatment-emergent adverse events (TEAEs) were identified using the preferred terms “autoimmune uveitis”, “iridocyclitis”, “iritis”, and “uveitis”, and were reported as both incidence and exposure adjusted incidence rates (EAIRs) per 100 pt years (PY) for all pts who received ≥1 BKZ dose.

Results Baseline characteristics were reflective of a pt population with moderate-to-severe axSpA (Table 1).

In the DBTP of BE MOBILE 1 and 2, uveitis TEAEs occurred in 11/237 (4.6%; EAIR/100 PY [95% CI]: 15.4 [7.7, 27.5]) and 2/349 (0.6%; 1.8 [0.2, 6.7]) of pts randomised to PBO and BKZ (% difference [95% CI]: 4.07 [1.71, 7.60]), respectively (Figure 1). In the 45 PBO-randomised (19.0%) and 52 BKZ-randomised (14.9%) pts with history of uveitis, uveitis TEAEs occurred in 20.0% (EAIR/100 PY [95% CI]: 70.4 [32.2, 133.7]) and 1.9% (6.2 [0.2, 34.8]) of pts, respectively.

In the pooled ph2b/3 trial data, total BKZ exposure was 2,034.4 PY (N=848), 130 (15.3%) pts had history of uveitis. Uveitis TEAEs occurred in 25 (2.9%; EAIR/100 PY [95% CI]: 1.2 [0.8, 1.8]) and 14 (10.8%; 4.6 [2.5, 7.7]) pts overall and with history of uveitis, respectively (Figure 1). All uveitis TEAEs were mild/moderate, one event led to discontinuation.

Conclusion The incidence rate of uveitis TEAEs was lower to Wk 16 in axSpA pts randomised to BKZ 160 mg Q4W vs PBO. In the largest pool of ph2b/3 data available at the time of this report, the incidence rate of uveitis with BKZ 160 mg Q4W remained low at 1.2/100 PY.

Reference [1]Boel A. Ann Rheum Dis 2019;78:1545–9; 2. Robinson PC. Arthritis Rheumatol. 2015;67(1):140–51; 3. Dick AD. J. Opthalmol 2013;120(4):777–87; 4. van der Heijde D. Ann Rheum Dis 2020;79:595–604; 5. Baraliakos X. Arthritis Rheumatol 2022;74 (suppl 9).

• Download figure
• Open in new tab
• Download powerpoint

Acknowledgements This study was funded by UCB Pharma. Medical writing support was provided by Costello Medical, funded by UCB Pharma.

Disclosure of Interests Martin Rudwaleit Speakers bureau: AbbVie, Boehringer Ingelheim, Chugai, Eli Lilly, Janssen, Novartis, Pfizer and UCB Pharma, Consultant of: AbbVie, Eli Lilly, Novartis and UCB Pharma, Matthew Brown Speakers bureau: Novartis., Consultant of: Clementia, Grey Wolf Therapeutics, Incyte, Ipsen, Pfizer, Regeneron and Xinthera, Grant/research support from: UCB Pharma, Floris A. van Gaalen Consultant of: Fees from Novartis; personal fees from AbbVie, BMS, Eli Lilly and MSD, Grant/research support from: Jacobus Stichting, Novartis, Stichting ASAS, Stichting Vrienden van Sole Mio and UCB Pharma, Nigil Haroon Consultant of: AbbVie, Eli Lilly, Janssen, Novartis and UCB Pharma, Lianne S. Gensler Consultant of: AbbVie, Acelyrin, Eli Lilly, Fresenius Kabi, Gilead, Janssen, MoonLake, Novartis, Pfizer and UCB Pharma, Grant/research support from: Novartis and UCB Pharma paid to institution, Carmen Fleurinck Employee of: UCB Pharma, Alexander Marten Employee of: UCB Pharma, Ute Massow Employee of: UCB Pharma, Natasha de Peyrecave Employee of: UCB Pharma, Thomas Vaux Employee of: UCB Pharma, Katy White Shareholder of: UCB Pharma, Employee of: UCB Pharma, Atul Deodhar Speakers bureau: Janssen, Novartis and Pfizer, Consultant of: AbbVie, Amgen, Aurinia, BMS, Celgene, Eli Lilly, Janssen, MoonLake, Novartis, Pfizer and UCB Pharma, Grant/research support from: AbbVie, BMS, Celgene, Eli Lilly, Janssen, Novartis, Pfizer and UCB Pharma, Irene van der Horst-Bruinsma Speakers bureau: AbbVie, BMS, MSD and Pfizer, Consultant of: Abbvie, Lilly, MSD, Novartis and UCB Pharma, Grant/research support from: Unrestricted grants received for investigator-initiated studies from AbbVie, MSD, Pfizer and UCB Pharma.