Introduction

Mirikizumab (miri), a p19-directed IL-23 antibody, has been shown to be effective in patients with moderately-to-severely active ulcerative colitis (UC) in Phase 3 trials (LUCENT-1 NCT03518086; LUCENT-2 NCT03524092).¹ The relationship between symptomatic, endoscopic, and clinical remission and levels of the inflammatory biomarker faecal calprotectin (fCAL) was studied for miri-treated patients enrolled in the trials.

Aims & Methods

This post hoc analysis evaluated patients treated with intravenous (IV) miri 300mg every 4 weeks (Q4W) until week (W)12 in induction (n=868) followed by subcutaneous miri (n=365) Q4W up to W52 (miri induction responders at W12 who were rerandomized for the maintenance period) or placebo. The improvement in fCAL at W12 and W52 between miri and placebo were compared using Cochran Mantel Haenszel, adjusting for randomization stratification factors. Missing data were imputed as nonresponse. The relationship between achieving symptomatic, endoscopic, or clinical remission (defined in Table) and fCAL levels at W4, W12 and W52 was assessed using receiver operating characteristic (ROC) approaches. Predictability was measured by area under the ROC curve (AUC), and AUC≤0.5 indicates no predictability. Optimal fCAL threshold was obtained based on Youden Index.

Results

Greater proportions of miri-treated patients compared to placebo achieved fCAL≤250 ug/g at W4, W12, and W52. A total of 19.0% vs. 12.5%, 34.3% vs. 20.1%, 50.7% vs 19.3% patients achieved fCAL≤250 ug/g at W4, W12, and W52 miri vs. placebo, respectively. Greater proportions of patients achieving symptomatic, endoscopic, and clinical remission reached the predefined threshold of fCAL≤250 ug/g or the optimum fCAL threshold obtained from the ROC (see Table footnote) in this study compared with those not achieving the endpoints (Table). W4 fCAL levels had 70.5% predictability for W12 endoscopic remission and 64.9% for clinical remission, but lower predictability for symptomatic remission (59.1%). W12 fCAL levels had 83.0% predictability for W12 endoscopic remission, 78.5% for clinical remission, and 67.4% for symptomatic remission. W52 fCAL levels had higher predictability for W52 endoscopic (76.6%) and clinical remission (72.7%) than for symptomatic remission (62.3%).

Table. Faecal Calprotectin Normalization at Week 12 in LUCENT-1 and Week 52 in LUCENT-2 per achievement of efficacy outcomes

Conclusion

These results support the use of fCAL as an early predictor of clinical outcomes and as a non-invasive biomarker for predicting clinical outcomes.

References

1. D’Haens G, et al. NEJM 2023;388(26):2444-2455. DOI: 10.1056/NEJMoa2207940

Disclosure

SV has received research support from AbbVie, Johnson & Johnson, Pfizer, Galapagos, and Takeda; lecture fees from AbbVie, Alimentiv, Arena Pharmaceuticals, AstraZeneca, Bristol Myers Squibb, Ferring, Galapagos, Genentech-Roche, Gilead, Janssen, Johnson & Johnson, Lilly, Materia Prima, Merck Sharp & Dohme, Pfizer, Takeda, Tillotts Pharma, and Zealand Pharma; and consulting fees from AbbVie, AbolerIS Pharma, AgomAb, Alimentiv, Arena Pharmaceuticals, AstraZeneca, Avaxia, BMS, Boehringer Ingelheim, Celgene, CVasThera, Dr Falk Pharma, Ferring, Galapagos, Genentech-Roche, Gilead, GSK, Hospira, Imidomics, Janssen, Johnson & Johnson, Lilly, Materia Prima, MiroBio, Morphic, MrMHealth, Mundipharma Merck, Pfizer, Prodigest, Progenity, Prometheus, Robarts Clinical Trials, Second Genome, Shire, Surrozen, Takeda, Theravance, Tillots Pharma, and Zealand Pharma.
ML has served as a Consultant for AbbVie, Pfizer, Takeda, Lilly, Bristol-Meyers Squibb, Target RWE, and Prometheus and has received research support from Pfizer, Takeda, and Janssen.
PD has consulted for Abbvie, Abivax, Adiso, Bristol Myers Squibb, GSK, Janssen, Lilly, Pfizer, and Takeda; grant support from Bristol-Myers Squibb, Janssen, Pfizer, and Takeda; Licensing royalties from PreciDiag.
CM has received consulting fees from AbbVie, Alimentiv, Amgen, AVIR Pharma Inc, Bristol Myers Squibb, Celltrion, Eli Lilly, Ferring, Fresenius Kabi, Janssen, McKesson, Mylan, Pendopharm, Pfizer, Prometheus Biosciences Inc., Roche, Sanofi, Takeda, Tillotts Pharma; speaker's fees from AbbVie, Amgen, AVIR Pharma Inc, Alimentiv, Bristol Myers Squibb, Eli Lilly, Ferring, Fresenius Kabi, Janssen, Organon, Pendopharm, Pfizer, Sanofi, Takeda, Tillotts Pharma; royalties from Springer Publishing; research support from AbbVie, Ferring, Pfizer.
F C-D, RM, and BZ are employees and minor shareholders of Eli Lilly and Company.
JP is an employee of Syneos Health.
ST has served as a paid consultant to AbbVie, Allergan, Amgen, Asahi, Bioclinica, Biogen, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, ChemoCentryx, Cosmo, Enterome, Equillium, Ferring, GSK, Genentech, Genzyme, Giuliani SpA, Immunocore, Immunometabolism, Janssen, Lilly, MSD, Merck, Mestag, Neovacs, Novo Nordisk, NPS Pharmaceuticals, Pfizer, Proximagen, Receptos, Roche, Satisfai Health, Sensyne Health, Shire, Sigmoid Pharma, Sorriso, Takeda, Topivert, UCB, VHsquared, Vifor, and Zeria; he has received grants and/or has grants pending from AbbVie, ECCO, Helmsley Trust, IOIBD, Janssen, Lilly, Norman Collisson Foundation, Pfizer, UCB, UKIERI, and Vifor; he has received honoraria from AbbVie, Amgen, Biogen, Ferring, Lilly, Pfizer, and Takeda; and he has had travel/accommodation expenses covered or reimbursed by AbbVie, Amgen, Biogen, Ferring, Lilly, Johnson & Johnson, Pfizer, and Takeda.
RP reports personal fees from Abbott, AbbVie, Alimentiv [formerly Robarts], Amgen, Arena Pharmaceuticals, AstraZeneca, Biogen, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Celltrion, Cosmos Pharmaceuticals, Eisai, Elan, Lilly, Ferring, Fresenius Kabi, Galapagos, Genentech, Gilead Sciences, GlaxoSmithKline, HC3 Communications, Janssen, Meducom, Merck, Mylan, Oppilan, Organon, Pandion Pharma, Pfizer, Progenity, Protagonist Therapeutics, Receptos, Roche, Sandoz, Satisfai Health, Schering-Plough, Shire, Sublimity Therapeutics, Takeda, Theravance Biopharma, Trellus Health, and UCB.

Introduction

Ulcerative colitis (UC) is associated with debilitating symptoms that impair the quality of life (QoL) of patients; restoration of QoL is an important long-term treatment goal.¹ Upadacitinib (UPA), an oral, reversible Janus kinase inhibitor approved for the treatment of UC, improves health-related QoL (HRQoL) and patient-reported outcomes (PROs) with 1 year (yr) of maintenance therapy.^2-4 This post hoc analysis of the U-ACTIVATE long-term extension (LTE) study evaluated the long-term efficacy of UPA in sustaining PROs and HRQoL outcomes in patients who had received up to a total of 4 years (yrs) of UPA maintenance therapy.

Aims & Methods

This analysis included patients who completed 1 yr (52 weeks [wks]) in the U-ACHIEVE maintenance study and received UPA15 mg once-daily (QD) (UPA15) or UPA 30 mg QD (UPA30) maintenance treatment in the U-ACTIVATE LTE study. Patients receiving UPA15 or UPA30 who achieved clinical remission per Adapted Mayo score at maintenance wk 52 continued their double-blind treatment upon entering the LTE study. Nonremitters receiving UPA15 were escalated to UPA30, those receiving UPA30 continued UPA30, and those assigned to PBO were escalated to UPA15, all in a blinded manner. The UPA UC program was not designed to compare UPA15 and UPA30 doses. Efficacy was assessed at LTE wks 0, 96, and 144 (data cutoff date: 30 June 2024) and included the percentage of patients who achieved absence of abdominal pain, absence of bowel urgency, Inflammatory Bowel Disease Questionnaire (IBDQ) response, IBDQ remission, and a meaningful within-person change (MWPC) in Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue; Short-Form Health Survey-36 version 2 Mental Component Score (SF-36v2 MCS), and SF-36v2 Physical Component Score (PCS). Data were reported using as-observed (AO) and modified nonresponder imputation (mNRI) methods (shown in Table). Safety was reported previously.²

Results

This analysis included 369 patients treated with UPA15 or UPA30 at wk 0 of LTE trial. In the AO analysis, patients treated with UPA15 or UPA30 achieved sustained improvements from LTE wk 0 to wk 144 in PROs and HRQoL assessments (Table), including the absence of abdominal pain, absence of bowel urgency, IBDQ response, IBDQ remission; and achieved MWPC in FACIT-Fatigue, SF-36v2 PCS, and SF-36v2 MCS. Similar results were observed for all endpoints with the more conservative mNRI analysis (Table).

Conclusion

Patients with UC who responded to induction therapy and received long-term UPA maintenance therapy showed a sustained absence of symptoms and improvements in HRQoL, suggesting that UPA maintains long-term improvements in patient-reported outcomes.

References

1. Turner D, Ricciuto A, Lewis A, D’Amico F, Dhaliwal J, et al. Gastroenterology. 2021;160:1570–83.
2. Panaccione R, et al. J Crohn’s Colitis. 2025;19(S1):i84-i86 [abstract].
3. AbbVie Inc. RINVOQ (Upadacitinib) [package insert] U.S. Food and Drug Administration website. https://www.rxabbvie.com/pdf/rinvoq_pi.pdf. Revised May 2023. Accessed 25 Feb 2025.
4. AbbVie DG& CoK. RINVOQ. Summary of Product Characteristics. European Medicine Agency website. https://www.ema.europa.eu/en/documents/product-information/rinvoq-epar-product-information_en.pdf. Revised Feb 2025. Accessed 25 Feb 2025.

Disclosure

Funding: AbbVie funded this study (U-ACTIVATE; NCT03006068) and participated in the study design, research, analysis, data collection, interpretation of data, reviewing, and approval of the publication. All authors had access to relevant data and participated in the drafting, review, and approval of this publication. No honoraria or payments were made for authorship.

Acknowledgments: AbbVie and the authors thank the participants, study sites, and investigators who participated in this clinical trial. Paulette A. Krishack, PhD, of AbbVie, provided medical writing support; Angela T. Hadsell, BA, of AbbVie, provided editorial support.

Joana Torres has received grant funding/speaker fees from and/or has participated in advisory boards for AbbVie, Lilly, Takeda, Janssen, and Pfizer.

Corey A Siegel has served as a consultant, advisor, and/or speaker for CME activities and/or received grant funding from AbbVie, BMS, Celltrion, Fresenius, Janssen, Lilly, Napo, Pfizer, Prometheus, Prometheus Labs, Roivant, and Takeda.

Julian Panés received consultancy fees/honorarium from AbbVie, Alimentiv, Athos, Atomwise, Boehringer Ingelheim, Celsius, Ferring, Galapagos, Genentech/Roche, GlaxoSmithKline, Janssen, Mirum, Nimbus, Pfizer, Progenity, Prometheus, Protagonist, Revolo, Sanofi, Sorriso, Surrozen, Takeda, and Wasserman, and has served on a data safety monitoring board for Alimentiv, Mirum, Sorriso, Sanofi, and Surrozen.

Edward V. Loftus Jr. has served as a consultant for AbbVie, Abivax, Amgen, Astellas, Avalo, Biocon, Boehringer Ingelheim, Bristol Myers Squibb, Celltrion, Eli Lilly, Fresenius Kabi, Genentech, Gilead, Iota Biosciences, Iterative Health, Janssen, Morphic Therapeutics, Ono Pharma, Takeda, and TR1X Bio; has received research grants from AbbVie, Genentech, Gilead, Janssen, Merck, and Takeda; and is a share owner of Exact Sciences and Moderna.

Remo Panaccione has received consulting fees, speaker fees, and research support from Abbott, AbbVie, Abbivax, Alimentiv Amgen, AnaptysBio, AstraZeneca, Biogen, Boehringer Ingelheim, Bristol Myers Squibb, Celgene Corporation, Celltrion, Cosmos Pharmaceuticals, Eisai, Elan, Eli Lilly, Ferring Pharmaceuticals, Galapagos, Fresenius Kabi, Genentech, Gilead Sciences, GlaxoSmithKline, JAMP Bio, Janssen Pharmaceuticals, Merck, Mylan, Novartis, Oppilan Pharma, Organon, Pandion Pharma, Pendopharm, Pfizer, Progenity, Prometheus Biosciences, Protagonist Therapeutics, Roche, Sandoz, Sanofi, Satisfai Health, Sublimity Therapeutics, Takeda Pharmaceuticals, Theravance Biopharma, Trellus, Viatris, Ventyx, and UCB.

Si Xuan, Nidhi Shukla, Ari Stromberg, Sina Ogholikhan, Leah Rizzo, and Dolly Sharma, are employees of AbbVie and may own stock options.

Gareth Parkesreports personal payments, honoraria, speaker fees, travel grants and/or fellowships from AbbVie, Allergan, Bristol Myers Squibb, Celltrion, Ferring, Galapagos, Janssen, Napp, Takeda, and Tillotts, and directorship and shareholding with Ampersand Health. TR reports personal grants from AbbVie; personal consulting fees from AbbVie, Arena, Aslan, AstraZeneca, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Eli Lilly, Ferring, Galapagos, Gilead, GSK, Heptares, LabGenius, Janssen, MonteRosa, Mylan, MSD, Novartis, Numab, Pfizer, Roche, Sandoz, Takeda, UCB and XAP; membership of the ECCO Scientific Committee, and membership in the UEG Scientific Committee; director of Endoread.

Introduction

Guselkumab (GUS) intravenous (IV) induction followed by subcutaneous (SC) maintenance with 200mg q4w or 100mg q8w was effective in the GALAXI 2 & 3 phase 3 treat-through studies of participants (pts) with moderately to severely active Crohn’s disease (CD), with similar efficacy between both maintenance doses in the overall study populations. Here, we evaluated the efficacy of maintenance doses in subgroups by baseline disease activity and severity and inflammatory burden at Week (Wk) 12 to determine if some pts may receive additional benefit from the higher maintenance dose.

Aims & Methods

Eligible pts had moderately to severely active CD (CDAI 220–450 and mean daily stool frequency score >3 or abdominal pain score >1), SES-CD ≥6 (≥4 for isolated ileal disease), and inadequate response or intolerance to oral corticosteroids, AZA, 6-MP, MTX, or biologics. Pts were randomly assigned to GUS 200mg IV at Wks 0, 4, and 8, followed by GUS SC 100mg q8w (N=286) or 200mg q4w (N=296). The studies also included placebo and ustekinumab arms, but this analysis focused on differences between GUS maintenance doses. Wk48 endpoints included clinical remission (CDAI <150) and endoscopic response (≥50% improvement in SES-CD or SES-CD ≤2). Analyses of subgroups by baseline disease activity (CDAI >300 or SES-CD >12), and inflammatory burden (CRP >5) or endoscopic response at Wk 12 were prespecified but not multiplicity controlled.

Results

In the pooled GALAXI 2 & 3 dataset, pts with baseline high disease activity (CDAI >300 or SES-CD >12) had numerically greater clinical and endoscopic outcomes at Wk 48 with 200mg q4w compared with 100mg q8w. Pts with baseline CDAI >300 had numerically greater percentages of clinical remission (200mg: 68.0% [83/122] vs 100mg: 55.1% [65/118], respectively) and endoscopic response (52.5% [64/122] vs 44.1% [52/118]) at Wk 48. Pts with baseline SES-CD >12 also had numerically greater percentages of these outcomes (clinical remission: 77.0% [94/122] vs 65.1% [82/126] and endoscopic response 67.2% [82/122] vs 58.7% [74/126]). Pts with baseline CDAI ≤300 or SES-CD ≤12 had similar Wk 48 outcomes for both maintenance doses. Pts with greater inflammatory burden (CRP >5mg/L) at Wk 12 or who were not in endoscopic response at Wk 12 also had numerically greater clinical and endoscopic outcomes at Wk 48 with 200mg compared with 100mg (Table). Pts with CRP ≤5mg/L or who were in endoscopic response at Wk 12 had similar clinical and endoscopic outcomes for both maintenance doses. Results for individual GALAXI 2 & 3 studies generally trended in the same direction for all subgroups.

Conclusion

Pts with high clinical or endoscopic disease severity at baseline, greater inflammatory burden after induction, or who had not achieved endoscopic response after induction showed greater clinical and endoscopic outcomes at Wk 48 with GUS 200mg SC q4w compared with 100mg SC q8w.

Disclosure

AA: AbbVie, Bristol Myers Squibb/Celgene, DiaSorin, Eli Lilly, Gilead, IBD Horizons, Johnson & Johnson, Pfizer, Takeda, and TLL Pharmaceuticals
TH: grants from AbbVie GK, Boston Scientific Corporation, EA Pharma Co. Ltd., JIMRO Co. Ltd., Kissei Pharmaceutical Co. Ltd., Kyorin Pharmaceutical Co. Ltd., Mitsubishi Tanabe Pharma Corporation, Mochida Pharmaceutical Co. Ltd., Nippon Kayaku Co. Ltd., Pfizer Inc., Takeda Pharmaceutical Co. Ltd., and Zeria Pharmaceutical Co. Ltd.; consulting fees from AbbVie GK, Abivax, Bristol Myers Squibb, EA Pharma Co. Ltd., Gilead Sciences, Janssen Pharmaceutical K.K., Lilly, Mitsubishi Tanabe Pharma Corporation, and Pfizer Inc.; lecture fees from AbbVie GK, EA Pharma Co. Ltd., Janssen Pharmaceutical K.K., JIMRO Co., Kissei Pharmaceutical Co. Ltd., Kyorin Pharmaceutical Co. Ltd., Mitsubishi Tanabe Pharma Corporation, Mochida Pharmaceutical Co., Ltd., Pfizer Inc., and Takeda Pharmaceutical Co. Ltd.
DTR: consulting/speaker fees/advisory board for AbbVie, Altrubio, Apex, Avalo, Bristol Myers Squibb, Buhlmann Diagnostics, Celgene, Connect BioPharma, Intouch Group, Iterative Health, Johnson & Johnson, Lilly, Pfizer, Samsung Neurologica, and Takeda; Altrubio, Datos Health, and Iterative Health stock options; grants from Takeda; membership on Board of Directors of Cornerstones Health, Inc and Crohn’s & Colitis Foundation’s Board of Trustees.
NAT, RVR, JY, KYYW, and ZY: employees of and may own Johnson & Johnson stock.
WR: speaker for AbbVie, Celltrion, Ferring, Johnson & Johnson, Galapagos Medice, MSD, Roche, Pfizer, Sobi, Takeda; consultant for AbbVie, Amgen, AOP Orphan, Boehringer Ingelheim, Bristol Myers Squibb, Calyx, Celltrion, Eli Lilly, Galapagos, Gilead, Index Pharma, Johnson & Johnson, Medahead, Microbiotica, Pfizer, Takeda; advisory board member for AbbVie, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, Celltrion, Galapagos, Johnson & Johnson, Pfizer; funding from AbbVie, Johnson & Johnson, Sandoz, Sanofi, Takeda.
BES: consulting fees from AbbVie, Adiso Therapeutics, Agomab, Alimentiv, Amgen, AnaptysBio, Arena Pharmaceuticals, AstraZeneca, Biolojic Design, Biora Therapeutics, Boehringer Ingelheim, Boston Pharmaceuticals, Celltrion, Equillium, Enthera, Enveda Biosciences, Evommune, Ferring, Galapagos, Genentech (Roche), Gilead Sciences, GlaxoSmithKline, Gossamer Bio, Imhotex, Index Pharmaceuticals, Innovation Pharmaceuticals, Inotrem, Kaleido, Kallyope, Merck, Microba, Mirador Therapeutics, Mobius Care, Morphic Therapeutics, MRM Health, Nexus Therapeutics, Nimbus Discovery, Odyssey Therapeutics, Progenity, Prometheus Biosciences, Prometheus Laboratories, Protagonist Therapeutics, Q32 Bio, Rasayana Therapeutics, Recludix Therapeutics, Reistone Biopharma, Sanofi, Sorriso Pharmaceuticals, Spyre Therapeutics, Sun Pharma, Surrozen, Target RWE, Teva, TLL Pharmaceutical, Tr1X, Union Therapeutics, Ventyx Biosciences, and Vividion Therapeutics; consulting /speaking fees from Abivax; consulting/speaking fees/other support from Lilly; research grants/consulting/speaking fees/other support from Bristol Myers Squibb, Johnson & Johnson, Pfizer, and Takeda; stock/options from Ventyx Biopharma.
SD: consultancy fees from AbbVie, Alimentiv, Allergan, Amgen, AstraZeneca, Athos, Biogen, Boehringer Ingelheim, Celgene, Celltrion, Eli Lilly, Enthera, Ferring, Gilead, Hospira, Inotrem, Johnson & Johnson, MSD, Mundipharma, Mylan, Pfizer, Roche, Sandoz, Sublimity, Takeda, TiGenix, UCB, and Vifor; lecture fees from AbbVie, Amgen, Ferring, Gilead, Janssen, Mylan, Pfizer, and Takeda.
RP: consulting fees from Abbivax, Abbott, AbbVie, Alimentiv, Amgen, AnaptsyBio, Arena Pharmaceuticals, AstraZeneca, Biogen, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Celltrion, Cosmos Pharmaceuticals, Eisai, Elan, Eli Lilly, Ferring, Fresenius Kabi, Galapagos, Genentech, Gilead Sciences, GlaxoSmithKline, JAMP Bio, Johnson & Johnson, Merck, Mylan, Novartis, Oppilan Pharma, Organon, Pandion Pharma, Pendopharm, Pfizer, Progenity, Prometheus Biosciences, Protagonist Therapeutics, Roche, Sandoz, Satisfai Health, Shire, Spyre Therapeutics, Sublimity Therapeutics, Takeda Pharmaceuticals, Theravance Biopharma, Trellus, Union Biopharma, Viatris, Ventyx, and UCB; speaker’s fees from AbbVie, Amgen, Arena Pharmaceuticals, Bristol-Myers Squibb, Celgene, Eli Lilly, Ferring, Fresenius Kabi, Gilead Sciences, Johnson & Johnson, Merck, Organon, Pfizer, Roche, Sandoz, Shire, and Takeda Pharmaceuticals; Advisory Boards for AbbVie, Alimentiv, Amgen, Arena Pharmaceuticals, AstraZeneca, Biogen, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Eli Lilly, Ferring, Fresenius Kabi, Genentech, Gilead Sciences, Glaxo-Smith Kline, JAMP Bio, Johnson & Johnson, Merck, Mylan, Novartis, Oppilan Pharma, Organon, Pandion Pharma, Pfizer, Progenity, Protagonist Therapeutics, Roche, Sandoz, Shire, Sublimity Therapeutics, Takeda Pharmaceuticals, and Ventyx.

Introduction

Faecal calprotectin (FC) is of value in differentiating Inflammatory Bowel Disease (IBD) from other causes of lower gastrointestinal (GI) symptoms and is recommended in national guidance. This study aims to examine its role and factors associated with faecal calprotectin requesting in primary care.

Aims & Methods

Retrospective open cohort study using Clinical Practice Research Datalink (CPRD Aurum) of adults aged over 18 years with lower GI symptoms between 2015 and 2019. FC requested 30 days before to 3 months after a lower GI symptom record in primary care were included. Logistic regression analysis explored patient level factors associated with FC testing. Referral pathways and outcomes (IBD diagnoses) of patients with and without FC testing were also examined.

Results

Of 741,190 symptomatic patients, only 18,320 (2.5%) had FC requested in primary care: median age 38.3 (IQR 28.9-50.7); 51.4% female. The rate of FC requesting in symptomatic patients increased from 0.02% in 2010 to 4.4% in 2019 (p=0.001).
FC value of <50 ug/g and 50-200 ug/g were predominantly seen in patients with abdominal pain (42.1% and 37.9% respectively), while FC > 200 ug/g was predominantly seen in patients with diarrhoea (45.3%). Factors associated with FC requesting included: increasing age (>70 years adjusted Odds Ratio 0.16 (95% CI 0.15-0.18)); female (0.89 (0.86-0.92); Black (0.61(0.56-0.66) or Asian (0.75 (0.70-0.80) ethnicity; obesity (0.89(0.85-0.93); lower socioeconomic status (0.91(0.86-0.98); comorbidity score >2 (0.73(0.68-0.79); current smoking (0.89(0.85-0.92)); change in bowel habit (7.31(6.90-7.75), rectal bleeding (2.04(1.95-2.13) or diarrhoea (2.88(2.78-2.99) compared to abdominal pain; and ex-smokers (1.06(1.03-1.11).
IBD was diagnosed in 21.5% of patients referred with a FC >200 ug/g, but only 2.9% of referred patients with a FC 50-200 ug/g. The only patients with a significant risk of IBD with FC 50-200ug/g were patients with rectal bleeding (8%), with the risk in all other patients only 1.7%. 27.8% patients with a normal FC test result were still referred to secondary care, of which only 0.4% had IBD.

Conclusion

Despite an increase in FC requests in recent years, only 4.4% of patients with relevant lower GI symptoms had an FC requested in primary care as recommended. Despite a negative FC test, a third of patients were still referred to secondary care, with very few diagnosed with IBD . Patients with an FC between 50 ug/g and 200 ug/g without rectal bleeding have a low risk of IBD and can be safety netted in primary care.