ORIGINAL RESEARCH
Sustained improvements in spinal pain, morning stiffness, fatigue, sleep, physical function and overall health- related quality of life with bimekizumab in patients with axial spondyloarthritis: 2-year results from two phase 3 studies

Helena Marzo- Ortega	,1,2 Victoria Navarro- Compan	,3 Maureen Dubreuil,4
Philip J Mease	,5 Marina Magrey,6 Martin Rudwaleit ,7
Maria- Antonietta D’Agostino,8,9 Karl Gaffney	,10 Jonathan Kay ,11
Christine de la Loge,12 Ute Massow,13 Vanessa Taieb,14 Tom Vaux,15 Atul Deodhar16

To cite: Marzo- Ortega H, Navarro- Compan V, Dubreuil M, et al. Sustained improvements in spinal pain, morning stiffness, fatigue, sleep, physical function and overall health- related quality of life with bimekizumab in patients with axial spondyloarthritis: 2- year results from two phase 3 studies. RMD Open 2025;11:e006013. doi:10.1136/ rmdopen-2025-006013
► Additional supplemental material is published online only. To view, please visit the journal online (https://doi. org/ 10. 1136/ rmdopen- 2025- 006013).

HM- O and VN- C are joint first authors.

Received 11 June 2025
Accepted 7 October 2025

© Author(s) (or their employer(s)) 2025. Re- use permitted under CC BY- NC. No commercial re- use. See rights and permissions. Published by BMJ Group.
For numbered affiliations see end of article.

Correspondence to
Professor Helena Marzo- Ortega; h. marzo- ortega@l eeds. ac. uk

RMD Open: first published as 10.1136/rmdopen-2025-006013 on 28 November 2025. Downloaded from https://rmdopen.bmj.com on 2 March 2026 by guest. Protected by copyright, including for uses related to text and data mining, AI training, and similar technologies.

ABSTRACT
Objective To assess the long-term effect of bimekizumab, a dual inhibitor of IL- 17A and IL- 17F, on patient- reported symptoms, function and health- related quality of life (HRQoL) in patients with axial spondyloarthritis (axSpA) from phase 3 studies and their open-l abel extension.
Methods BE MOBILE 1 (non- radiographic- axSpA) and 2 (radiographic- axSpA) comprised 16- week double- blind placebo- controlled and 36-week maintenance periods. From week 16, all patients received subcutaneous bimekizumab 160 mg every 4 weeks. At week 52, eligible patients could enrol in the open-l abel extension BE MOVING and continue bimekizumab treatment. Spinal pain (rated on a numerical rating scale from 0 (no pain) to 10 (maximum pain)), morning stiffness (Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) average of Q5/6), fatigue (BASDAI Q1; Functional Assessment of Chronic Illness Therapy (FACIT)- Fatigue subscale), sleep quality (Medical Outcomes Study (MOS) Sleep Scale Index II), physical function (Bath Ankylosing Spondylitis Functional Index (BASFI)) and HRQoL (36-Item Short Form Survey (SF- 36) physical component summary (PCS)/mental component summary (MCS); Ankylosing Spondylitis Quality of Life (ASQoL) questionnaire) were reported to week 104.
Results In total, 494/586 (84.3%) patients entered BE MOVING at week 52; 456 completed week 104. Patients reported substantial changes from baseline to week 104 in total spinal pain (-4.3), nocturnal spinal pain (-4.3), morning stiffness (-4.3) and fatigue (BASDAI Q1: -3.4; FACIT- Fatigue: +9.9). Over half reported total and nocturnal spinal pain scores ≤3 at week 104. Similar improvements to week 104 were shown in sleep (MOS- Sleep Scale: +10.2), physical function (BASFI: -2.9) and HRQoL (SF- 36 PCS: +12.4; ASQoL: -5.6).
Conclusions Bimekizumab treatment resulted in sustained improvements in patient- reported symptoms and their impacts across the full disease spectrum of axSpA over 2 years,
WHAT IS ALREADY KNOWN ON THIS TOPIC
⇒ The primary treatment goal for patients with axial spondyloarthritis (axSpA) is sustained control of disease- related symptoms to improve daily functioning and overall health- related quality of life (HRQoL). It is therefore important to assess the efficacy of new treatment options both long-term and across the full patient population.
⇒ Bimekizumab, which selectively inhibits IL- 17F in addition to IL- 17A, has been shown to improve axSpA symptoms (eg, spinal pain, morning stiffness and fatigue) and their impacts (eg, sleep, physical function and HRQoL), over 5 years in patients with radiographic (r-)axSpA and up to 52 weeks in patients across the full disease spectrum
underscoring its long-term potential for improving patients’ daily lives.
Trial registration numbers NCT03928704, NCT03928743, NCT04436640
INTRODUCTION
Axial spondyloarthritis (axSpA) is a chronic, immune-mediated inflammatory disease which is now recognised as a spectrum, encompassing patients both with and without definite radiographic sacroiliitis (radiographic (r-) and non- radiographic (nr-) axSpA, respectively).1–3 AxSpA is characterised by spinal pain, morning stiffness and fatigue, which can greatly impact a patient’s

WHAT THIS STUDY ADDS
⇒ Here, we demonstrate the longer- term efficacy of bimekizumab across the full disease spectrum of axSpA and a range of patient- reported outcomes, from the 52- week BE MOBILE 1 and 2 studies and the first 52 weeks of their open-l abel extension, BE MOVING.
⇒ In addition to the previously reported improvements at 2 years of bimekizumab treatment in nocturnal spinal pain, morning stiffness, fatigue, physical function and HRQoL, this analysis provides longitudinal changes over time. These results demonstrate that 2 years of treatment with bimekizumab leads to sustained improvements in spinal pain, morning stiffness, fatigue, sleep, physical function and HRQoL, with considerable proportions of patients achieving thresholds for improvement or low severity across these outcomes.
HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY
⇒ The long- term and sustained benefits of bimekizumab in clinically important patient- reported symptoms and functional impacts demonstrate its potential for improving patients’ HRQoL. Further data from the ongoing open-l abel extension will assess the safety and efficacy of bimekizumab to 3 years.
ability to carry out their daily activities and impair their health-related quality of life (HRQoL).4 5 The primary treatment goal for patients with axSpA is to achieve greater long- term control of disease symptoms in order to improve their daily function and overall HRQoL.6
Bimekizumab is a humanised monoclonal IgG1 antibody that selectively inhibits interleukin (IL)- 17F in addition to IL- 17A. Both cytokines are key mediators of inflammation that have been implicated in the pathogenesis of axSpA.3 7 Bimekizumab was recently approved as a treatment for axSpA by both the European Medicines Agency and the US Food and Drug Administration.8 9 Bimekizumab has demonstrated long- term efficacy and was well tolerated up to 5 years in patients with r-axSpA in the phase 2b BE AGILE study and its open-label extension (OLE).10–12 In the phase 3 studies BE MOBILE 1 (nr-axSpA) and BE MOBILE 2 (r-axSpA) and the first year of their combined OLE, BE MOVING, bimekizumab also demonstrated sustained efficacy in disease activity and safety up to 2 years for patients across the full disease 13 spectrum.
Patient-reported outcomes are of high importance to patients, with a previous Delphi survey showing that patients with axSpA viewed pain as the most important domain to measure in a clinical trial; stiffness and fatigue were also rated highly.14 15 These symptoms can exacerbate each other and be associated with wider-ranging impacts such as poorer sleep quality, impaired physical function and overall reduced HRQoL. Conversely, improvements in nocturnal spinal pain have been shown to positively affect fatigue and sleep, which are both associated with overall improved physical functioning and HRQoL for patients with r-axSpA.16 Despite patient perspectives playing an increased role in clinical decision making, levels of pain and fatigue remain high for many patients despite treatment with currently available medications.17
In the BE MOBILE 1 and 2 studies, bimekizumab has previously shown rapid improvements in patient- reported symptoms, function and HRQoL up to 52 weeks.14 18 19 Improvements from baseline at week 104 in nocturnal spinal pain, morning stiffness, fatigue, physical function and HRQoL have also been shown with bimekizumab treatment.13 This study presents the longitudinal changes over time in these outcomes with 2 years of bimekizumab exposure from BE MOBILE 1 and 2 and the first year of the OLE, BE MOVING. Further, this study presents results of total spinal pain, an additional measure of fatigue (the Functional Assessment of Chronic Illness Therapy (FACIT) fatigue subscale), and an evaluation of sleep quality, as well as the proportions of patients achieving thresholds of improvement or low severity across patient-reported outcomes. By reporting the effects of 2 years of bimekizumab treatment across a wide range of patient-reported outcomes, this study aims to present a complete picture of the impact of long- term bimekizumab treatment on key symptoms across the full disease spectrum of axSpA.
METHODS
Study design and patients
The study design and inclusion and exclusion criteria for the BE MOBILE 1 (NCT03928704) and 2 (NCT03928743) studies and their combined ongoing OLE, BE MOVING (NCT04436640), have been reported previously.13 20 Both BE MOBILE 1 and 2 comprised a 16-week doubleblind placebo-controlled period, during which patients received either subcutaneous bimekizumab 160 mg or placebo every 4 weeks (Q4W), followed by a 36-week maintenance period, during which all patients received subcutaneous bimekizumab 160 mg Q4W. At week 52, all patients who completed either study without meeting any withdrawal criteria were eligible to enrol in BE MOVING, during which all patients continued to receive bimeki- zumab 160 mg Q4W for the subsequent 112 weeks. BE MOBILE 1 and 2 were conducted in parallel at 83 sites across 14 countries; adults aged ≥18 years with active axSpA, defined as Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ≥4 and spinal pain (BASDAI Question (Q)2) ≥4, were enrolled.20 BE MOBILE 1 included patients with axSpA classified as nr- axSpA, according to the Assessment of SpondyloArthritis international Society (ASAS) classification criteria, and without sacroiliitis as defined by modified New York (mNY) criteria. BE MOBILE 2 included patients with axSpA classified as r-axSpA, as per mNY criteria. All patients in BE MOBILE 2 also fulfilled ASAS criteria. Here we report results from BE MOBILE 1 and 2 and the first 52 weeks of BE MOVING (104 weeks total).
Outcomes
Detailed descriptions of the following outcome measures have been reported previously.14 18
Spinal pain
Total and nocturnal spinal pain were each scored by patients on a Numerical Rating Scale (NRS) from 0 to 10, with higher scores indicating greater pain. The question ‘How much pain of your spine due to spondylitis do you have?’ was given for total spinal pain, and ‘How much pain of your spine due to spondylitis do you have at night?’ for nocturnal spinal pain. Patients were asked to consider the average amount of pain in the preceding week in their answers.
Morning stiffness
Morning stiffness was evaluated using BASDAI Q5 (morning stiffness severity) and Q6 (morning stiffness duration) scores; the average of these scores is presented. BASDAI items were rated using a 0–10- point NRS with higher scores indicating greater symptom severity/dura- tion. For Q6, a score of 0 indicates zero hours, 5 indicates 1 hour and 10 indicates 2 or more hours.21
Fatigue
Fatigue was assessed using BASDAI Q1 on an NRS from 0 to 10, with a higher score indicating greater fatigue. BASDAI Q1 severity thresholds are presented based on clinically validated cut-off points: severe (≥7), moderate (≥4 to <7), mild (≥2 to <4) and no/minimal (<2) fatigue.22 Fatigue was also assessed using the FACIT-Fatigue subscale, which consists of 13 items scored from 0 (‘not at all’) to 4 (‘very much’) with a total score ranging from 0 to 52 and which has been shown to be a valid measure of fatigue for use in axSpA.23 Higher scores indicate a lower burden of fatigue. The proportion of patients achieving a meaningful improvement in FACIT-Fatigue score is reported, defined as a ≥8-point improvement from baseline (only in patients with a FACIT-Fatigue score of ≤44 at baseline, ie, those who were able to achieve the improve- ment).23
Sleep quality
Sleep quality was assessed using the nine-item Medical Outcomes Study (MOS) Sleep Scale Index II, which has previously been used to measure sleep quality in axSpA.18 24 25 This questionnaire assesses the frequency various sleep problems are experienced during the previous 4 weeks on a five-point scale ranging from 0 (‘none of the time’) to 5 (‘all of the time’). Scores were transformed linearly to range from 0 to 100, with higher scores indicating better sleep. Results are reported in the subset of patients with impaired sleep at baseline (MOS Sleep Scale Index II <45).24
Physical function
Physical function was assessed using the Bath Ankylosing Spondylitis Functional Index (BASFI), which assesses functional anatomical limitations and ability to perform everyday activities and has a range of 0–10, with lower scores indicating better physical function.26
Health-related quality of life
Overall HRQoL was assessed using the generic 36- Item Short Form Survey (SF- 36) Physical Component Summary (PCS) and Mental Component Summary (MCS), where a T-score of 50 (SD of 10) reflects the US general population mean (SD).27 For SF- 36 MCS, results are reported in the subset of patients with impairment at baseline (SF- 36 MCS <45).27 Disease-specific HRQoL was assessed using the Ankylosing Spondylitis Quality of Life (ASQoL) questionnaire. ASQoL is an 18-item questionnaire assessing the impact of axSpA on patient HRQoL, where a score of ‘1’ is given for each item if a patient responds ‘yes’ and ‘0’ if the response is ‘no’. The ASQoL score is obtained by summing each score and ranges from 0 to 18, with higher ,
scores indicating worse HRQoL.28
Statistical analysis
The statistical analyses used in BE MOBILE 1, BE MOBILE 2 and BE MOVING have been described previously.13 20 Here, we report mean (95% CI) scores and mean (95% CI) change from baseline in the above outcomes to Week 104 for all patients randomised in BE MOBILE 1 and 2, pooled across nr-axSpA and r-axSpA, applying relevant imputation as described below. We also report to Week 104 the proportion of patients achieving low scores in total and nocturnal spinal pain, morning stiffness and BASFI (0/≤1/≤2/≤3), and the proportion of patients achieving different severity levels for BASDAI Q1 using severity thresholds derived in a recent psychometric anal- ysis.22 The proportions of patients achieving a meaningful improvement in SF- 36 PCS (≥5-point increase from base- line)18 and ASQoL (≥4-point decrease from baseline) are also reported.29
Continuous outcomes were imputed using multiple imputation and reported as mean change from baseline. For multiple imputation, intermittent missing data were imputed using the Markov- Chain Monte Carlo method, followed by regression for monotone missing data (ie, where all study participant data were missing after a given time point). The imputation model included region, feeder study (BE MOBILE 1 or 2), treatment at randomisation (bimekizumab or placebo) and the value at baseline as fixed effects. The proportion of patients achieving specific thresholds of response is presented using nonresponder imputation (NRI, where missing data and patients not entering BE MOVING were treated as a nonresponse) and observed case (OC), with the exception of the proportion of patients achieving different BASDAI Q1 severity thresholds, which is presented using MI. The proportion of patients affirming ‘yes’ to individual ASQoL items is reported using OC.
RESULTS
Patient disposition and baseline characteristics
Of the 586 patients randomised in BE MOBILE 1 (n=254) and BE MOBILE 2 (n=332), 494/586 (84.3%) entered the OLE, BE MOVING, at week 52. A total of 456/586

Figure 1 Mean improvement in spinal pain and morning stiffness (MI), as rated on an NRS (0–10) Pooled randomised set. Error bars represent 95% CI. Improvement indicated by decreased scores; patients were asked to consider the average amount of pain or morning stiffness in the preceding week. aIncludes all patients regardless of randomisation to BKZ or PBO. BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BKZ, bimekizumab; CfB, change from baseline; MI, multiple imputation; NRS, numerical rating scale; PBO, placebo; Q5/6, question 5/6; Q4W, every 4 weeks.

patients had completed week 104 by the July 2023 data cut (77.8% of randomised patients and 92.3% of patients entering BE MOVING).30
As previously reported, baseline mean total and nocturnal spinal pain, morning stiffness (mean of BASDAI Q5 and 6), fatigue (BASDAI Q1 and FACIT- Fatigue), sleep quality, physical function (BASFI) and HRQoL (SF- 36 PCS/MCS and ASQoL) scores were similar across placebo-randomised and bimekizumab- randomised patients.14 18 Absolute values of all outcomes at baseline, week 52 and week 104 are presented in online supplemental table S1. A graphical summary of study results is provided in online supplemental figure S1.
Spinal pain and morning stiffness
At baseline, mean total spinal pain, nocturnal spinal pain and morning stiffness (mean of BASDAI Q5 and 6) scores across all randomised patients were 7.2, 6.7 and 6.8, respectively. The mean (95% CI) reductions from baseline in total spinal pain, nocturnal spinal pain and morning stiffness scores achieved at week 52 (-4.2 (-4.4 to –4.0), -4.2 (-4.4 to –4.0) and -4.2 (-4.4 to –4.0), respectively) were sustained to week 104 (-4.3 (-4.5 to –4.1), -4.3 (-4.5 to –4.1) and -4.3 (-4.6 to –4.1); figure 1A–C).

Figure 2 Proportion of patients achieving thresholds for low spinal pain or morning stiffness at week 104 (NRI, OC), as rated on an NRS (0–10). Pooled randomised set: includes all patients regardless of randomisation to BKZ or placebo. Improvement indicated by decreased scores; patients were asked to consider the average amount of pain or morning stiffness in the preceding week. BKZ, bimekizumab; NRI, non- responder imputation; NRS, numerical rating scale; OC, observed case; Q4W, every 4 weeks.

The proportions of patients achieving increasingly stringent thresholds for low spinal pain and morning stiffness, as previously reported to week 52,14 were also sustained to week 104 (figure 2A–C). At week 104, 53.9% and 57.3% of patients achieved total and nocturnal spinal pain scores ≤3, respectively, with 29.7% and 37.7% achieving scores ≤1, and 13.1% and 22.9% achieving scores of 0, representing an absence of spinal pain. Similarly, at week 104, 55.6% of patients achieved

bars represent 95% CI. Improvement indicated by decreased scores for BASDAI Q1 (range: 0–10) and increased scores for FACIT- Fatigue (range: 0–52). aIncludes all patients regardless of randomisation to BKZ or PBO. BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BKZ, bimekizumab; CfB, change from baseline; FACIT, Functional Assessment of Chronic Illness Therapy; MI, multiple imputation; PBO, placebo; Q1, question 1; Q4W, every 4 weeks.

morning stiffness scores ≤3, with 31.7% achieving scores ≤1 and 15.2% achieving resolution of morning stiffness (score=0).
Fatigue
Across all randomised patients, at baseline the mean BASDAI Q1 score was 6.5 and mean FACIT-Fatigue score was 30.9. The mean (95% CI) improvement in BASDAI Q1 from baseline achieved to week 52 (-3.1 (-3.3 to –2.9)) was sustained to week 104 (-3.4 (-3.6 to –3.2); figure 3A). Mean (95% CI) improvement in FACIT- Fatigue from week 52 to week 104 was similarly sustained (+9.9 (9.1 to 10.7) to +9.9 (9.1 to 10.8); figure 3B).
According to previously validated BASDAI Q1 fatigue severity thresholds,22 51.9% of patients had severe fatigue at baseline. However, by week 52, more than half of patients (56.7%) were considered to have no more than mild fatigue. This proportion increased to 64.7% at week 104 (figure 4A). Among patients with a FACIT- Fatigue score of ≤44 at baseline, more than half achieved a FACIT-Fatigue response (≥8-point improvement) at weeks 52 and 104 (figure 4B).
Sleep
At baseline, the mean MOS- Sleep Index II score for patients with impaired scores (<45) at baseline was 37.3. At week 52, the mean (95% CI) score had improved by +9.9 (8.9 to 10.9) and change from baseline at week 104 was +10.2 (9.3 to 11.2).

Physical function
At baseline, the mean BASFI score across all randomised patients was 5.3. Improvements in mean (95% CI) BASFI score from baseline achieved at week 52 (-2.8 (-3.0 to –2.6)) were sustained to week 104 (-2.9 (-3.1 to –2.7); figure 5A). At week 104, 52.4% and 30.7% of patients achieved scores <4 and <2, respectively (figure 5B).
Health-related quality of life
Generic measure
At baseline, overall mean SF- 36 PCS score was 34.0 among all randomised patients. Improvements in mean (95% CI) scores from baseline achieved at week 52 (+12.0 (11.3 to 12.8)) were sustained to week 104 (+12.4 (11.7 to 13.2)) with mean scores approaching the lower bound of the US general population norm (figure 6A).27 In addition, at weeks 52 and 104, more than 60% of patients achieved a ≥5-point improvement in SF- 36 PCS score (figure 7A).
As previously reported, mean SF- 36 MCS scores were relatively high at baseline (>50) and remained relatively stable over time.14 In the population of all randomised patients with an impaired SF- 36 MCS score (<45) at baseline (n=134; mean at baseline: 37.9), mean (95% CI) improvements from baseline were achieved with bimeki- zumab treatment at week 52 (+9.3 (7.4 to 11.2)) which were sustained to week 104 (+8.4 (6.5 to 10.3); online supplemental figure S2).

Figure 4 Proportion of patients achieving A) fatigue severity thresholds, as measured by BASDAI Q1 (MI) and B) meaningful improvement in fatigue, assessed as a ≥8- point improvement in FACIT- Fatigue (NRI, OC). Pooled randomised set (N=586): includes all patients regardless of randomisation to BKZ or placebo. aAnalysis includes patients with a FACIT- Fatigue score ≤44 at baseline (n=520). BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BKZ, bimekizumab; FACIT, Functional Assessment of Chronic Illness Therapy; MI, multiple imputation; NRI, non- responder imputation; OC, observed case; Q1, question 1; Q4W, every 4 weeks.

Disease-specific measure
Mean (95% CI) improvements from baseline (9.1) in ASQoL achieved at week 52 (-5.6 (-6.0 to –5.2)) were also sustained to week 104 (-5.6 (-6.0 to –5.2); figure 6B).
At week 104, approximately 60% of patients achieved a ≥4-point improvement in ASQoL (figure 7B).
At baseline, 10/18 individual ASQoL items had over 50% of patients responding ‘yes’, including four items

Figure 5 Mean improvement in physical function (MI) and proportion of patients achieving thresholds for low impairment of physical function at week 104, as measured by BASFI (NRI, OC) Pooled randomised set. Error bars represent 95% CI. CfB improvements indicated by decreased scores (range: 0–10). aIncludes all patients regardless of randomisation to BKZ or PBO. BASFI, Bath Ankylosing Spondylitis Functional Index; BKZ, bimekizumab; CfB, change from baseline; MI, multiple imputation; NRI, non- responder imputation; OC, observed case; PBO, placebo; Q4W, every 4 weeks.

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Figure 7 Proportion of patients achieving meaningful improvements in HRQoL, as measured by SF- 36 PCS and ASQoL (NRI, OC). Pooled randomised set: includes all patients regardless of randomisation to BKZ or PBO. Improvements indicated by increased scores for SF- 36 PCS. Improvements indicated by decreased scores for ASQoL (range: 0–18). aAnalysis includes patients with ASQoL score ≥4 at baseline. ASQoL, Ankylosing Spondylitis Quality of Life; BKZ, bimekizumab; HRQoL, health- related quality of life; NRI, non- responder imputation; OC, observed case; PBO: placebo; Q4W, every 4 weeks; SF- 36 PCS, 36- Item Short Form Survey Physical Component Summary.

RMD Open: first published as 10.1136/rmdopen-2025-006013 on 28 November 2025. Downloaded from https://rmdopen.bmj.com on 2 March 2026 by guest. Protected by copyright, including for uses related to text and data mining, AI training, and similar technologies.

represent 95% CI. Improvements indicated by increased scores for SF- 36 PCS. Improvements indicated by decreased scores for ASQoL (range: 0–18). aFor SF- 36 PCS, group-l evel mean scores between 47 and 53 (blue shaded area) can be considered within the ‘average’ or ‘normal’ range for the US general population (mean score in US general population is 50 (SD:10)).27 bIncludes all patients regardless of randomisation to BKZ or PBO. ASQoL, Ankylosing Spondylitis Quality of Life; BKZ, bimekizumab; CfB, change from baseline; HRQoL, health- related quality of life; MI, multiple imputation; PBO, placebo; Q4W, every 4 weeks; SF- 36 PCS, 36-I tem Short Form Survey Physical Component Summary.

				

				

				

				

				

				

				
				
Figure 8 Proportion of patients responding ‘yes’ to individual ASQoL items at baseline and weeks 52 and 104 (OC). Pooled randomised set (N=586): includes all patients regardless of randomisation to bimekizumab or PBO. Items are ordered by decreasing percentage of patients reporting ‘yes’ at baseline. ASQoL, Ankylosing Spondylitis Quality of Life; OC: observed case; PBO: placebo.

with over 70% of patients responding ‘yes’ (figure 8). At week 52, less than 45% of patients responded ‘yes’ to each item. This was sustained to week 104, where less than 40% of patients responded ‘yes’ to each item.
DISCUSSION
Previous analyses of the phase 3 BE MOBILE 1 and 2 studies have shown that bimekizumab treatment resulted in rapid and substantial improvements in patient- reported symptoms and their impacts over 52 weeks, and improvements from baseline at 2 years of treatment.13 14 18 In addition to these previously reported results, this study provides insights into longitudinal changes over time in key patient- reported symptoms with 2 years of bime- kizumab treatment and highlights the proportions of patients achieving thresholds of improvement or low severity across these measures. The long-term control of these key symptoms, which negatively impact patients’ HRQoL, is an important treatment goal for axSpA.
These results from BE MOBILE 1 and 2 and their OLE, BE MOVING, demonstrate that improvements after 52 weeks’ bimekizumab treatment in patient-reported spinal pain, morning stiffness, fatigue, sleep, physical function and overall HRQoL were sustained to week 104 both for patients with nr-axSpA and those with r- axSpA. By week 104, over half of all patients achieved total and nocturnal pain scores ≤3, lower than the ≥4 cut- off for spinal pain that was an inclusion criterion for patients entering BE MOBILE 1 and 2. In the Delphi panel used to update the axSpA core outcome set, pain was voted the most important domain by 95% and 97% of patients with axSpA in the symptom- modifying and disease- modifying therapy scenarios, respectively, indicating the continued importance of assessing this patient- reported symptom in phase 3 trials of novel therapies.15
In this study, over 50% of patients reported a ≥8-point improvement in FACIT-Fatigue by week 52, which was sustained to week 104. The proportion of patients reporting no/minimal fatigue for BASDAI Q1 (a score of 0 or 1) also increased slightly between weeks 52 and 104 to almost a third, indicating that improvements in fatigue were sustained throughout the second year of treatment with bimekizumab. A major contributor to fatigue for patients with axSpA may be poor sleep quality, with 46% of patients estimated to have moderate to severe insomnia.31 In this study, sleep quality was improved by around 10 points on a 0–100 scale by week 52, which was sustained to week 104.
Improvements in physical function were also sustained to week 104, with over half of patients achieving a BASFI score ≤3 and almost a third achieving a BASFI score ≤1, indicating low impairment of physical function at 2 years. Overall HRQoL improved from baseline with bimekizumab treatment, with mean SF- 36 PCS scores approaching the lower bound of the US general population norm by week 52, sustained to week 104, and over 60% of patients showing ≥5-point improvement in SF- 36 PCS by week 104. A similar percentage of just below 60% of patients achieved a meaningful improvement in ASQoL (≥4 points) at week 104. Moreover, for all ASQoL items, over half of patients did not answer ‘yes’ after 104 weeks’ treatment and some ASQoL items had a reduction of over 50% in the percentage of patients answering ‘yes’ between baseline and week 104. These results indicate continued improvements in patients’ ability to carry out daily activities, which is likely to also have wider-reaching effects on aspects such as employment, mood and interpersonal relationships.31
To our knowledge, this is the first dedicated report on the impact of treatment across a wide range of patient- reported outcomes to 2 years for the full disease spectrum of axSpA, including both r- axSpA and nr-axSpA. The outcomes reported herein are aligned with the axSpA core outcome set, which have been judged by both patients and experts to include the most relevant disease domains and cover many aspects of a patient’s daily life.15 32 33 Other strengths of this study include the long 2-year follow-up period, high patient retention and maintenance of response demonstrated even when using the most stringent methods of imputation (NRI).
A limitation of this study is the lack of established within-patient improvement thresholds for outcomes such as spinal pain and morning stiffness. To mitigate this, results using different thresholds for these outcomes have been presented. ASAS- HI, part of the ASAS- OMERACT core outcome set for axSpA, was not assessed in the BE MOBILE 1 and 2 or BE MOVING trials, but the ASQoL has similar content to that of the ASAS- HI and has been validated for use in both nr-axSpA and r- axSpA.32–34 In this study, clear improvements in HRQoL, assessed using both SF- 36 PCS and ASQoL, were maintained through 2 years’ treatment.
Although this study presents a clear picture of key patient-reported symptoms of axSpA and considers symptoms which have previously been highlighted as being of importance to evaluate during axSpA treatment, the evaluation of other patient-reported outcomes, such as emotional status and physical activity, would have been of interest to explore for further insights. Further, validation of the findings using objective measures of these symptoms, such as actigraphy for sleep or the Ankylosing Spondylitis Performance Index for physical function, would strengthen the evidence presented; however, these were not prespecified for evaluation in the BE MOBILE trials or their OLE. Patient- reported symptoms stratified by axSpA subtype were also not evaluated in this study, limiting the ability of this analysis to identify whether there are differences between axSpA subtypes. Finally, although assumed to be part of the standard care approach at individual treatment centres, the impact of non-pharmacological treatments supplementing bimeki- zumab treatment such as physiotherapy or psychological support was not assessed in this study.
CONCLUSIONS
Dual inhibition of IL- 17A and IL- 17F with bimekizumab resulted in sustained improvements over 2 years in pain, morning stiffness, fatigue, sleep, physical function and overall HRQoL across the full disease spectrum of axSpA. These long-term improvements in clinically important patient-reported symptoms, function and HRQoL underscore the potential benefit of bimekizumab therapy on patients’ daily lives.
Author affiliations
1NIHR Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds, UK
2Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK
3Department of Rheumatology, La Paz University Hospital, IdiPaz, Madrid, Spain 4Section of Rheumatology, Boston University School of Medicine, Boston, Massachusetts, USA
5Swedish Medical Center, Providence St. Joseph Health and University of Washington, Seattle, Washington, USA
6Case Western Reserve University, University Hospitals, Cleveland, Ohio, USA 7Department of Internal Medicine and Rheumatology, Bielefeld University, Medical School and University Medical Center, Klinikum Bielefeld, Bielefeld, Germany 8Department of Rheumatology, Università Cattolica del Sacro Cuore, Roma, Italy 9Department of Rheumatology, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
10Norfolk and Norwich University Hospital NHS Trust, Norwich, UK
11Division of Rheumatology, Department of Medicine, UMass Chan Medical School and UMass Memorial Medical Center, Worcester, Massachusetts, USA
12UCB, Brussels, Belgium
13UCB, Monheim am Rhein, Germany
14UCB, Colombes, France
15UCB, Slough, UK
16Division of Arthritis and Rheumatic Diseases, Oregon Health & Science University, Portland, Oregon, USA
Acknowledgements The authors thank the patients and their caregivers, in addition to all the investigators and their teams who contributed to these

studies. The authors also acknowledge Celia Menckeberg, PhD, UCB, Breda, The Netherlands, for publication coordination and editorial assistance, and Olivia Wakeman, BSc, and James Evry, MSc, Costello Medical, Cambridge, UK, for medical writing and editorial assistance. These studies were funded by UCB. HMO is supported by the National Institute for Health Research (NIHR) Leeds Biomedical Research Centre (BRC), The Leeds Teaching Hospitals NHS Trust and by an NIHR Senior Clinical and Practitioner Research Award. The views expressed are those of the authors and not necessarily those of the UK NHS, NIHR, or Department of Health. These results were previously presented at EULAR 2024.
Contributors Substantial contributions to study conception and design: HM- O, VN- C, MD, PJM, MM, MR, M-AD'A, KG, JK, CdlL, UM, VT, TV and AD; substantial contributions to analysis and interpretation of the data: HM- O, VN- C, MD, PJM, MM, MR, M-AD'A, KG, JK, CdlL, UM, VT, TV and AD; drafting the article or reviewing it critically for important intellectual content: HM- O, VN- C, MD, PJM, MM, MR, M- AD'A, KG, JK, CdlL, UM, VT, TV and AD; final approval of the version of the article to be published: HM- O, VN- C, MD, PJM, MM, MR, M- AD'A, KG, JK, CdlL, UM, VT, TV and AD. VT acts as guarantor for this work.
Funding This article was based on the original studies BE MOBILE 1 (NCT03928704), BE MOBILE 2 (NCT03928743) and BE MOVING (NCT04436640), which were sponsored by UCB. Support for third- party writing assistance for this article, provided by Olivia Wakeman, BSc, and James Evry, MSc, Costello Medical, Cambridge, UK, was funded by UCB in accordance with Good Publication Practice 2022 guidelines (https://www.ismpp.org/gpp-2022).
Disclaimer The views expressed are those of the authors and not necessarily those of the UK NHS, NIHR or Department of Health.
Competing interests HM- O: Speaking honoraria and/or consultancy fees from AbbVie, Amgen, Biogen, Eli Lilly and Company, Janssen, MoonLake Immunotherapeutics, Novartis, Pfizer, Takeda and UCB; research grants from Janssen, Novartis, Pfizer and UCB; VN- C: Speakers bureau for AbbVie, Eli Lilly and Company, Fresenius Kabi, Janssen, MSD, Novartis, Pfizer and UCB; consultant for AbbVie, Alfasigma, Eli Lilly and Company, Galapagos, MoonLake Immunotherapeutics, MSD, Novartis, Pfizer and UCB; grant/research support from AbbVie and Novartis; MD: Educational grant from Pfizer paid to institution; consulting fees (eg, advisory boards) from Amgen and UCB; PJM: Research grants from AbbVie, Acelyrin, Amgen, Bristol Myers Squibb, Eli Lilly and Company, Janssen, Novartis, Pfizer, Sana and UCB; consulting fees from AbbVie, Acelyrin, Amgen, Bristol Myers Squibb, Cullinan, Eli Lilly and Company, GSK, Inmagene, Janssen, MoonLake Immunotherapeutics, Novartis, Pfizer, Takeda, UCB and Ventyx; speakers bureau fees from AbbVie, Amgen, Eli Lilly and Company, Janssen, Novartis, Pfizer and UCB; MM: Consultancy fees from AbbVie, Bristol Myers Squibb, Eli Lilly and Company, Novartis, Pfizer and UCB, and research grants from AbbVie, Bristol Myers Squibb and UCB; MR: Speakers bureau from AbbVie, Boehringer Ingelheim, Chugai, Eli Lilly and Company, Janssen, Novartis, Pfizer, UCB; consultant of AbbVie, Eli Lilly and Company, Novartis, UCB; M- AD'A: Speaking honoraria and/or consultancy fees from Amgen, AbbVie, Boehringer Ingelheim, Bristol Myers Squibb, Eli Lilly and Company, Janssen, Galapagos, Novartis, Pfizer and UCB; KG: Speakers bureau: AbbVie, Eli Lilly and Company, Novartis, UCB; consultant for AbbVie, Eli Lilly and Company, Novartis, UCB; grant/research support from: AbbVie, Gilead, Eli Lilly and Company, Novartis, UCB; JK: Research Support (paid to UMass Chan Medical School): Aker BioMarine AS, Biogen, Galapagos and SetPoint Medical Corp; consultant for AbbVie, Alvotech Swiss AG, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, Fresenius Kabi, Novartis, Organon, Pfizer, Samsung Bioepis, Sandoz, Scipher Medicine, Teijin Pharma, UCB, Viatris and Yuhan Corp; independent data monitoring committee member for Inmagene and Kolon TissueGene; royalties: Wolters Kluwer NV (for UpToDate); CdlL: Consultant to UCB; UM: Employee of UCB; VT, TV: Employee and shareholder of UCB; AD: Speaker for Eli Lilly and Company, J&J, Novartis, Pfizer and UCB; consultant for Bristol Myers Squibb, Eli Lilly and Company, J&J, MoonLake Immunotherapeutics, Novartis, Pfizer and UCB; grant/ research support from Bristol Myers Squibb, Celgene, Eli Lilly and Company, Novartis, Pfizer and UCB.
Patient consent for publication Not applicable.
Ethics approval This study involves human participants and the BE MOBILE 1, BE MOBILE 2 and BE MOVING studies were conducted in accordance with the Declaration of Helsinki and the International Conference on Harmonisation Guidance for Good Clinical Practice. Ethical approvals were obtained from the relevant institutional review boards at participating sites. All patients provided written informed consent in accordance with local requirements. Participants gave informed consent to participate in the study before taking part.
Provenance and peer review Not commissioned; externally peer reviewed.
Data availability statement Data are available on reasonable request. Data are available on reasonable request. Underlying data from this manuscript may be requested by qualified researchers 6 months after product approval in the USA and/or Europe, or global development is discontinued, and 18 months after study completion. Investigators may request access to anonymised individual patient-l evel data and redacted trial documents which may include analysis- ready datasets, trial protocols, annotated case report forms, statistical analysis plans, dataset specifications and clinical study reports. Prior to the use of the data, proposals need to be approved by an independent review panel at www.Vivli.org and a signed data sharing agreement will need to be executed. All documents are available in English only, for a prespecified time, typically 12 months, on a password- protected portal.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer- reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.
Open access This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY- NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non- commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non- commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.
ORCID iDs
Helena Marzo- Ortega https://orcid.org/0000-0002-9683-3407
Victoria Navarro- Compan https://orcid.org/0000-0002-4527-852X
Philip J Mease https://orcid.org/0000-0002-6620-0457
Martin Rudwaleit https://orcid.org/0000-0001-5445-548X
Karl Gaffney https://orcid.org/0000-0002-7863-9176
Jonathan Kay https://orcid.org/0000-0002-8970-4260
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