Introduction

JAK inhibitors (JAKi) are small molecules capable of crossing the placenta via passive diffusion or active extracellular transport from early pregnancy.¹ Data on the risks of in utero JAKi exposure are limited,² particularly regarding pregnancy outcomes, infant infections, vaccine responses, and childhood development.

Aims & Methods

We conducted a multicenter retrospective JAKi and pregnancy observational study supported by the ECCO Collaborative Network for Exceptionally Rare Case Reports (CONFER). Pregnant women with inflammatory bowel disease (IBD) exposed to tofacitinib (TOFA), upadacitinib (UPA), or filgotinib (FILGO) during pregnancy were enrolled from 21 centers across 15 countries. Data collected included maternal demographics, IBD characteristics, disease activity, medication use - including timing and duration of JAKi exposure - along with maternal, pregnancy, and infant outcomes.

Results

Of 43 JAKi exposed pregnancies, 17 (39.5%) were unplanned. Disease activity was present in 22 (51.2%) of the pregnancies. One-in-five women initiated JAKi in pregnancy (n=8, 18.6%). Abortion occurred in 8 cases, at a median gestational age (GA) of 8.5 weeks (range 3-16). Of these, 3 (7.0%) were spontaneous and 5 (11.6%) induced, with two terminations due to concerns about potential adverse effects of JAKi treatment. Of the remaining 35 pregnancies 26 (74.3%) were exposed to TOFA (5 mg BID (n=9), 10 mg BID (n=17)), 8 (22.9%) to UPA (30 mg daily (n=2), 45 mg daily (n=6)) and one (2.9%) to FILGO (200 mg daily). The majority received JAKi treatment throughout pregnancy (n=24, 68.6%). Discontinuation of JAKi during the 1^st or 2^nd trimester was followed by disease activity in 7 of 11 cases (63.6%). Maternal complication risk was low: no cases of DVT or (pre)eclampsia; premature rupture of membranes (GA 34–37) occurred in 3 cases, and 4 women required hospitalization due to infection or other complications. Among 35 live births, one infant (2.9%) was preterm (GA 34), three (8.6%) were small for gestational age, one (2.9%) had an Apgar score <7 at 5 minutes, and no congenital abnormalities were reported. Follow-up infant data are shown in table 1. One-third of breastfeeding women continued JAKi treatment. A high adherence rate to the national immunization schedule was seen. Three (8.6%) skipped the live rotavirus vaccine due to in uteroJAKi exposure. No adverse effects were reported following live attenuated or inactivated vaccines, and no malignancies were observed.

Table 1. Follow-up in 31 infants after in utero exposure to JAK-inhibitors
	n	(%)	Notes
Duration, months – median (range)	17	(1-88)
Proportion of breastfeeding women (n=24) who continued JAKi treatment	7	(29.2)
Infection resulting in hospitalization (age 0-4 months)	2	(6.5)	Moderate-to-severe maternal disease activity treated with systemic corticosteroids and initiation of upadacitinib at gestational weeks 8 and 28, respectively. No infection-related sequelae.
Normal development	31	(100)
Follow the national immunization program	26	(74.3)
Live BCG vaccine provided (age 0-1 month)	5	(16.1)	No adverse effects reported.
Live Rotavirus vaccine provided (age 1.5-6 months)	13	(41.9)	No adverse effects reported.
Live MMR vaccine provided (age ≥ 12 months)	13	(41.9)	No adverse effects reported.

Conclusion

In this global multicenter study of JAKi exposure during pregnancy in women with IBD, maternal complication rates were low, and no increased risk of adverse pregnancy outcome were observed among live births. While disease activity was common, particularly following early discontinuation of JAKi, infant outcomes - including development, infection risk, and vaccine response - were reassuring. These findings provide important preliminary safety data to guide decision-making regarding the use of JAKi in pregnancy, though further prospective studies are needed to confirm long-term safety.

References

1. Fein KC, Arral ML, Kim JS, et al. Placental drug transport and fetal exposure during pregnancy is determined by drug molecular size, chemistry, and conformation. J Control Release 2023;361:29-39.
2. Torres J, Chaparro M, Julsgaard M, et al. European Crohn's and Colitis Guidelines on Sexuality, Fertility, Pregnancy, and Lactation. J Crohns Colitis 2023;17:1-27.

Disclosure

M. Julsgaard: Advisory board for AbbVie. G. Santana: Speaker and advisory board for pfizer.

Introduction

Up to 40% of patients with acute severe ulcerative colitis (ASUC) do not respond to infliximab (IFX)(1) presumably due to insufficient drug exposure (1, 2). We investigated whether personalised IFX induction using predefined serum concentrations was superior to standard dosing.

Aims & Methods

In this prospective, multi-centre trial, adult IFX-naive steroid-refractory ASUC patients were randomised 1:1 to standard (SD) or personalised IFX dosing (PD). After an initial 5 mg/kg IFX infusion, SD was 5 mg/kg IFX at week 2 and 6. In PD, additional 5 mg/kg IFX infusions were administered guided by a Bayesian pharmacokinetic algorithm (iDose™) aiming at IFX serum concentrations >28 ug/mL day 0-28 and >15 ug/mL day 29-42 (3). The primary composite endpoint was clinical and endoscopic response at day 42 (Lichtiger score <10 and ≥3 points drop and UCEIS ≥2 points drop from baseline). Video-endoscopies were performed at baseline, day 42 and 182 and scored by 2 expert readers (XR) with adjudication by a third XR and post hoc also by the DovaVision UC AI tool (AI-R)(4). Key secondary endpoints were day 42 clinical response, day 42 endoscopic response, day 182 clinical remission (Lichtiger ≤3), day 182 endoscopic remission (UCEIS ≤1 on all components), and safety.

Results

48 patients were randomised (23 PD/25 SD) and 31 completed the 26-week study (19 PD/12 SD). Patient characteristics were comparable. Median cumulative IFX dose until day 42 was 18.41 mg/kg [1.77, 20.27] for PD vs 13.79 mg/kg [10.38, 14.82] for SD. The primary composite endpoint at day 42 was not met with XR (57% in PD vs 44% in SD; p=0.564). However, AI-R showed a significantly higher composite response rate in PD (74% in PD vs 32% in SD; p=0.0047). PD showed higher day 42 clinical response vs SD (91% vs 64%; p=0.039). Day 42 endoscopic response was observed in 57% in PD vs 44% in SD (p=0.564) with XR and 74% in PD vs 32% in SD with AI-R (p=0.0047). The proportion of patients in clinical and endoscopic remission at day 182 was higher in PD than in SD (65% vs 36%; p=0.082). Day 182 endoscopic remission with AI-R was higher in PD (52% in PD and 20% in SD; p=0.0337). SAEs occurred in 9% of patients on PD vs 20% of patients on SD. Following an interim analysis, the trial was discontinued based on futility.

Table 1. Baseline characteristics

	Personalised treatment (n=23)	Standard treatment (n=25)
Gender = Male (%)	11 (47.8)	15 (60.0)
Age (year) (median [IQR])	37.00 [24.50, 57.50]	42.00 [30.00, 56.00]
Disease duration (years) (median [IQR])	1.75 [0.62, 5.30]	6.16 [2.61, 17.21]
Naive to advanced therapy (%)	18 (78.3)	21 (84.0)
Lichtiger score (median [IQR])	14 [13, 16]	14 [12, 15]
Total Mayo score (median [IQR])	11 [11, 11]	11 [10, 11]
UCEIS (median [IQR])	6 [5, 7]	6 [5, 7]
CRP (mg/L) (median [IQR])	49.00 [35.70, 70.30]	51.00 [17.00, 105.00]
Albumin (g/L) (median [IQR])	26.00 [23.00, 30.50]	31.00 [23.00, 34.00]

Advanced therapy was defined as treatment with any biologics, JAK inhibitor or S1P modulator. IQR = interquartile range; UCEIS = Ulcerative Colitis Endoscopic Index of Severity, CRP = C-reactive protein.

Conclusion

Personalised IFX dosing was superior to standard dosing in ASUC when endoscopies were read by AI. This is the first IBD study where the primary endpoint, missed by expert assessment, was overturned and met by AI assessment instead. This demonstrates the potential of AI to fundamentally improve clinical trial methodology.

References

1. Seow CH, Newman A, Irwin SP, Steinhart AH, Silverberg MS, Greenberg GR. Trough serum infliximab: a predictive factor of clinical outcome for infliximab treatment in acute ulcerative colitis. Gut. 2010;59(1):49-54.
2. Papamichael K, Van Stappen T, Vande Casteele N, Gils A, Billiet T, Tops S, et al. Infliximab Concentration Thresholds During Induction Therapy Are Associated With Short-term Mucosal Healing in Patients With Ulcerative Colitis. Clin Gastroenterol Hepatol. 2016;14(4):543-9.
3. Ungar B, Mazor Y, Weisshof R, Yanai H, Ron Y, Goren I, et al. Induction infliximab levels among patients with acute severe ulcerative colitis compared with patients with moderately severe ulcerative colitis. Aliment Pharmacol Ther. 2016;43(12):1293-9.
4. Byrne M, Requa J, Panaccione R, Panes J, Bressler B, East JE, et al. Development and Validation of a novel AI-based computer vision solution for Ulcerative Colitis severity scoring on video for real world using high-volume expert-annotated video frames. United European Gastroenterol J. 2025 Oct.

Disclosure

This project received grant support from Pfizer Inc. and research support from Baysient LLC, Buhlmann Laboratories and Dova Health Intelligence.

Introduction

Obefazimod (Obe) is an oral, once-daily (QD), small molecule which enhances expression of microRNA-124 and has been studied in two Phase 2 induction trials and subsequent open-label maintenance studies [1-3] in patients (pts) with moderately to severely active ulcerative colitis (UC). Here we report efficacy and safety of two Phase 3, 8-week, induction trials in adult pts with UC from ABTECT-1 [NCT05507203] and ABTECT-2 [NCT05507216].

Aims & Methods

The multicenter, randomized, double-blind, placebo-controlled ABTECT trials enrolled pts with moderate-to-severe UC (defined as modified Mayo score (MMS)≥ 5, with rectal bleeding sub-score (RBS) ≥ 1 and centrally read endoscopic score >2) who had inadequate response, loss of response, or intolerance to at least one prior therapy (with no upper limit), including corticosteroids, immunosuppressants, biologics, S1P receptor modulators and/or JAK inhibitors. Pts were randomized 2:1:1 to Obe 50 mg QD (Obe-50), Obe 25 mg QD (Obe-25) or placebo (PBO) for 8 weeks. The primary endpoint was clinical remission (per MMS) and secondary endpoints included clinical response, endoscopic improvement, symptomatic remission, and histo-endoscopic mucosal improvement (HEMI).

Results

1272 pts were randomized and treated in ABTECT-1 (636) and ABTECT-2 (636). In both trials, baseline demographics and disease characteristics were similar between groups; 45.3% and 49.3% of pts had inadequate response to 1 or more advanced therapies. A significantly higher proportion of pts receiving Obe-50 (ABTECT-1:21.7%, ABTECT-2: 19.8%) versus PBO (2.5% and 6.3%) achieved clinical remission (Obe-50-PBO difference: ABTECT-1: 19.3%, p<0.0001; ABTECT-2: 13.4%, p=0.0001) and met all key secondary endpoints in both trials. A significantly higher proportion of pts receiving Obe-25 versus PBO achieved clinical remission (Obe-25-PBO difference: 21.4%, p<0.0001) and met all key secondary endpoints in ABTECT-1. In a pooled analysis, both Obe-50 and Obe-25 met all primary and secondary endpoints with nominal significance (p<0.0001) (Table). The overall rate of serious adverse events and treatment emergent adverse events (TEAEs) leading to study drug discontinuation for pts treated with Obe were similar to PBO. Proportions of pts who reported at least one TEAE in ABTECT-1 were 59.4%, 46.9%, and 53.2% for Obe-50, Obe-25, and PBO, respectively. For ABTECT2, TEAEs occurred in 61.0%, 50.9%, and 48.4% for Obe-50, Obe-25, and PBO, respectively. The most frequent TEAE was headache (Obe-50: 20.8-25.8%; Obe-25: 14.5-15.6%; PBO: 5.7). The headaches were mild, transient, short in duration and not a barrier to treat as evidenced by a low discontinuation rate of 0-1.6%. No signal was observed for serious, severe, or opportunistic infections or malignancies.

Table: 8-week induction efficacy of obefazimod in ABTECT-1 and ABTECT-2 Phase 3 studies, and pooled ABTECT-1 and ABTECT-2^‡

	ABTECT-1					ABTECT-2					Pooled ABTECT-1 and ABTECT-2
Efficacy Endpoints at week 8, % (n)	PBO N= 158	Obe-25 N= 160	Obe-50 N= 318	Between group diff. Obe-25 vs PBO	Between group diff. Obe-50 vs PBO	PBO N= 159	Obe-25 N= 159	Obe-50 N= 318	Between group diff. Obe-25 vs PBO	Between group diff. Obe-50 vs PBO	PBO N= 317	Obe-25 N= 319	Obe-50 N= 636	Between group diff. Obe-25 vs PBO	Between group diff. Obe-50 vs PBO
Clinical remission	2.5 (4)	23.8 (38)	21.7 (69)	21.4 p<0.0001	19.3 p<0.0001	6.3 (10)	11.3 (18)	19.8 (63)	5.1 p=0.1034¥	13.4 p=0.0001	4.4 (14)	17.6 (56)	20.8 (132)	13.2a p<0.0001	16.4a p<0.0001
Clinical response	28.5 (45)	65.6 (105)	61.0 (194)	37.2 p<0.0001	32.6 p<0.0001	33.3 (53)	53.5 (85)	63.2 (201)	20.1 p=0.0002¥	29.6 p<0.0001	30.9 (98)	59.6 (190)	62.1 (395)	28.6a p<0.0001	31.2a p<0.0001
Endoscopic improvement†	5.7 (9)	37.5 (60)	33.3 (106)	32.0 p<0.0001	27.8 p<0.0001	10.1 (16)	22.0 (35)	35.5 (113)	12.0 p=0.0029¥	25.4 p<0.0001	7.9 (25)	29.8 (95)	34.4 (219)	21.9a p<0.0001	26.6a p<0.0001
HEMI	3.2 (5)	23.8 (38)	23.0 (73)	20.7 p<0.0001	20.0 p<0.0001	7.5 (12)	13.2 (21)	23.9 (76)	5.7 p=0.0932¥	16.4 p<0.0001	5.4 (17)	18.5 (59)	23.4 (149)	13.2a p<0.0001	18.2a p<0.0001
Symptomatic remission*†	17.7 (28)	42.5 (68)	41.2 (131)	24.9 p<0.0001	23.7 p<0.0001	22.0 (35)	33.3 (53)	40.3 (128)	11.4 p=0.0227	18.0 p<0.0001	19.9 (63)	37.9 (121)	40.7 (259)	18.1a p<0.0001	21.0a p<0.0001
NRI is used for subjects with missing outcome at Week 8 and subjects reporting any IE prior to Week 8 % Difference is for Obe minus placebo and is based on estimated common risk difference using the Mantel-Haenszel weights adjusting for the randomization stratification factors: inadequate response to advanced therapies (yes/no), baseline oral corticosteroids usage (yes/no), and region (Japan/rest of world) [ABTECT-2 only]. p-values are two sided. a: for pooled analysis, all p-values are nominal Clinical remission: stool frequency sub-score (SFS) ≤1, rectal bleeding sub-score (RBS) = 0 and endoscopic sub-score ≤1 Clinical response: decrease from baseline in the MMS ≥ 2 points and ≥30% from baseline, plus a decrease in RBS ≥ 1 or an absolute RBS ≤ 1 Endoscopic improvement: endoscopic sub-score ≤1 Symptomatic remission: RBS=0, SFS <1 HEMI: combination of histologic improvement (Geboes histologic score ≤3.1) and endoscopic improvement (endoscopy sub-score ≤1) * Symptomatic remission was an “other secondary” endpoint, not multiplicity controlled, for the FDA protocol † Endoscopic improvement/symptomatic remission were co-primary endpoints for the EMA protocol and were met by both doses in both trials ‡ Hierarchical testing strategy was used starting with 50mg for the primary endpoint followed by the key secondary endpoints; the 25mg was subsequently tested for the primary endpoint followed by the key secondary endpoints. ¥ 25mg did not meet the primary endpoint at week 8 in ABTECT-2 in the FDA testing protocol, therefore p-values for key secondary endpoints for the 25mg arm in ABTECT-2 are nominal

Conclusion

In both ABTECT induction trials, primary and secondary endpoints were met; obe treatment led to statistically significant improvements in clinical, endoscopic, symptomatic and combined endoscopic-histologic endpoints at week 8. Obe was well tolerated with no new safety signals identified.

References

1. Vermeire S, et al. J Crohns Colitis. 2023; 17: 1689-1697
2. Vermeire S, et al. The Lancet Gastroenterology & Hepatology. 2022; 7: 1024-1035.
3. Vermeire S, et al. J Crohns Colitis. 2025 ; 19 : jjaf074

Disclosure

Authors reports following potential conflicts of interest:
BES: Abbvie, Abivax, Adiso Therapeutics, Agomab, Alimentiv, Amgen, AnaptysBio, Arena Pharmaceuticals, Artugen Therapeutics, Astra Zeneca, Biolojic Design, Biora Therapeutics, Boehringer Ingelheim, Bristol Myers Squibb, Celltrion, Equillium, Enthera, Enveda Biosciences, Evommune, Ferring, Fzata, Galapagos, Genentech (Roche), Gilead Sciences, GlaxoSmithKline, Gossamer Bio, Imhotex, Index Pharmaceuticals, Innovation Pharmaceuticals, Kaleido, Kallyope, Lilly, Merck & Co., Microba, Microbiotica, Mitsubishi Tanabe, Mobius Care, Morphic Therapeutics, MRM Health, Nexus Therapeutics, Nimbus Discovery, Odyssey Therapeutics, OSE Immunotherapeutics, Janssen, Palisade Bio, Pfizer, Protagonist Therapeutics, Q32 Bio, Rasayana Therapeutics, Recludix Therapeutics, Reistone Biopharma, Sanofi, Sorriso Therapeutics, Spyre Therapeutics, Takeda, Target RWE,Teva, TLL Pharmaceutical, Tr1X, Trex Bio, Union Therapeutics, Ventyx Biosciences.
SV: AbbVie, Abivax, AbolerIS Pharma, AgomAb, Alimentiv, Arena Pharmaceuticals, AstraZeneca, Avaxia, BMS, Boehringer Ingelheim, Celgene, CVasThera, Cytoki Pharma, Dr Falk Pharma, Ferring, Galapagos, Genentech-Roche, Gilead, GSK, Hospira, Imidomics, Janssen, J&J, Lilly, Materia Prima, MiroBio, Morphic, MrMHealth, Mundipharma, MSD, Pfizer, Prodigest, Progenity, Prometheus, Robarts Clinical Trials, Second Genome, Shire, Surrozen, Takeda, Theravance, Tillots Pharma AG, Zealand Pharma.
LPB: Abbvie, Abivax, Adacyte, Alimentiv, Amgen, Applied Molecular Transport, Arena, Banook, Biogen, BMS, Celltrion, Connect Biopharm, Cytoki Pharma, Enthera, Ferring, Fresenius Kabi, Galapagos, Genentech, Gilead, Gossamer Bio, GSK, IAC Image Analysis, Index Pharmaceuticals, Inotrem, Janssen, Lilly, Medac, Mopac, Morphic, MSD, Nordic Pharma, Novartis, Oncodesign Precision Medicine, ONO Pharma, OSE Immunotherapeuthics, Pandion Therapeuthics, Par' Immune, Pfizer, Prometheus, Protagonist, Roche, Samsung, Sandoz, Sanofi, Satisfay, Takeda, Telavant, Theravance, Thermo Fischer, Tigenix, Tillots, Viatris, Vectivbio, Ventyx, Ysopia.
SD: AbbVie, Ferring, Hospira, Johnson & Johnson, Merck, MSD, Takeda, Mundipharma, Pfizer Inc, Tigenix, UCB Pharma, Vifor, Biogen, Celgene, Allergan, Celltrion, Sandoz, Boehringer Ingelheim.
PSD: Abbvie, Abivax, Adiso, Alimentiv, Bristol Meyer Squibb, Celltrion, Genentech, Geneoscopy, Janssen, Pfizer, Takeda.
MD: Abbvie, Abivax, Arena Pharmaceuticals, Astra Zeneca, Boehringer Ingelheim International GmbH, Bristol-Meyer Squibb, Eli Lilly and Company, F. Hoffmann-La Roche Ltd, Genentech Inc, Gilead, Janssen Pharmaceuticals, Merck, Pfizer Inc, Prometheus Biosciences, Takeda Pharmaceuticals.
HT: Abbvie, Abivax, Dr Falk Pharma, ferring, Galapagos, Microbiotica, MSD, Pfizer, Takeda.
BS: AbbVie, Abivax, Boehringer Ingelheim, Bristol Myers Squibb, Dr. Falk Pharma, Eli Lilly, Endpoint Health, Falk, Galapagos, Gilead, Janssen, Landos, Materia Prima, PredictImmune, Pfizer, and Takeda; AlfaSigma, CED Service GmbH, MSD, Ferring, Galapagos, Tr1x bio
TH: Mitsubishi Tanabe Pharma Corporation, EA pharma Co. Ltd., AbbVie GK, JIMRO Co. Ltd., Zeria Pharmaceutical Co. Ltd., Kyorin Pharmaceutical Co. Ltd., Nippon Kayaku Co. Ltd., Takeda Pharmaceutical Co. Ltd., Pfizer Inc., Mochida Pharmaceutical Co. Ltd., Boston Scientific Corporation, Kissei Pharmaceutical Co. Ltd, Janssen Pharmaceutical K.K., Pfizer Inc., Eli Lilly, Gilead Sciences, Bristol Myers Squibb, Abivax.
XT: Celltrion, AbbVie, Johnson & Johnson, Lilly, Takeda, Alpha Sigma, Dr. Falk, Abivax, Biogen, Fresenius Kabi, MSD, Pfizer, Tillotts, and Thabor Therapeutics.
RA: AbbVie, Abivax, AstraZeneca, Bristol-Myers Squibb, Celltrion Healthcare, Galapagos, Johnson&Johnson, Lilly, MSD, Pfizer, and Takeda Pharma
US: AbbVie, Abivax, Amgen, Galapagos, Janssen, Eli Lilly, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Gilead Sciences, Pfizer, Roche,Takeda Pharmaceuticals
AA: AbbVie, Abivax, AG Pharma, Alfa Sigma, Astra Zeneca, Biogen, Boehringer Ingelheim, Bristol-Myers Squibb, Celltrion, Eli-Lilly, Enthera, Ferring, Galapagos, Gilead, Giuliani, Janssen, Lionhealth, MSD, Nestlé, Novartis, Pfizer, Protagonist Therapeutics, Roche, Samsung Bioepis, Sanofi, Sandoz, Takeda, Teva Pharmaceuticals, Tillots Pharma
FB: AbbVie, Amgen, Eurogenerics, J&J, Arena Pharmaceuticals, Celltrion, Ferring, Galapagos, Janssen, Merck Sharp & Dohme, Pfizer Inc, Takeda, Celgene, Fresenius Kabi, Sandoz
DTR: Abbvie, Abivax SA, Altrubio, Athos Therapeutics, Inc, Bristol-Myers Squibb, Celltrion, Connect BioPharma, Eli Lilly & Co., Genentech (Roche) Inc., Iterative Health, Janssen Pharmaceuticals, Johnson & Johnson, Merck & Co., Odyssey Therapeutics, Pfizer, Sanofi, Spyre, Takeda Pharmaceuticals, Vedanta Biosciences, and Ventyx.

Introduction

Small intestinal bacterial overgrowth (SIBO) is a clinical syndrome with abdominal complaints and malabsorption. Despite concerns over cure rates, recurrence, and antibiotic resistance, rifaximin (RIF) remains the primary treatment. Berberine (BBR), an affordable traditional medicine, has demonstrated gut microbiota modulation, making it a promising alternative.

Aims & Methods

We conducted an open-label, non-inferiority randomized controlled trial (BRIEFSIBO) comparing BBR and RIF in SIBO patients. Patients were randomly assigned to receive either RIF or BBR. The primary outcome was breath test (BT) conversion to negative, with symptom scores and the Bristol stool scale as secondary outcomes.

Results

A total of 186 patients completed the study. No significant baseline differences were found between groups in age, gender, BMI, smoking, or alcohol use. BBR demonstrated non-inferior efficacy to RIF for primary outcome (BT eradication) at Week 2 (ITT: BBR 45%, RIF 51%, Z=2.407, P=0.008; PP: BBR 44%, RIF 47%, Z=2.4787, P=0.007) and Week 6 (ITT: BBR 53%, RIF 44%, Z=4.3244, P<0.001; PP: BBR 54%, RIF 45%, Z=4.077, P<0.001). What's more, BBR demonstrated non-inferior efficacy to RIF for secondary outcome (clinical improvement) at Week 2 (ITT: BBR 68%, RIF 75%, Z=2.9209, P=0.0017; PP: BBR 73%, RIF 72%, Z=3.3531, P=0.0004) and Week 6 (ITT: BBR 75%, RIF 80%, Z=2.8514, P=0.0022; PP: BBR 81%, RIF 86%, Z=3.0747, P=0.0011). Following a four-week period of discontinuation, the rate of combined expiratory and symptomatic relapse in patients treated with RIF was 8.57%. In contrast, no such relapses were observed in patients treated with BBR. BT values at 60–90 minutes and AUC decreased in both groups, though RIF showed recurrent peak values during follow-up. A novel breath peak acceleration parameter, reflecting local gut gas load, decreased in both groups. BBR significantly improved bloating at Week 6, whereas RIF improved bowel movement frequency. At Week 6, patients were classified into response, relapse, and nonresponse groups to identify optimal candidates for each drug. RIF responders showed significant improvement in bloating and bowel-related symptoms (P<0.05). Baseline gut microbiota analysis revealed significant β diversity differences between three groups in BBR but not in RIF. Genus-level microbiota composition differed between responders, with BBR responders exhibiting higher baseline proportions of Phascolarctobacterium, Klebsiella, and Haemophilus, and lower Coprobacter. At Week 6, both groups showed enriched Bacteroides, while BBR responders had elevated Phascolarctobacterium, Streptococcus, and Haemophilus, with lower Bifidobacterium.

Conclusion

BBR is non-inferior to RIF for SIBO treatment and offer a promising and cost-effectiveness new option.

References

1. Pimentel M, Saad RJ, Long MD, et al. ACG Clinical Guideline: Small Intestinal Bacterial Overgrowth. Am J Gastroenterol 2020;115(2):165-78. doi: 10.14309/ajg.0000000000000501
2. Bushyhead D, Quigley EMM. Small Intestinal Bacterial Overgrowth-Pathophysiology and Its Implications for Definition and Management. Gastroenterology 2022;163(3):593-607. doi: 10.1053/j.gastro.2022.04.002
3. Quigley EMM, Murray JA, Pimentel M. AGA Clinical Practice Update on Small Intestinal Bacterial Overgrowth: Expert Review. Gastroenterology 2020;159(4):1526-32. doi: 10.1053/j.gastro.2020.06.090
4. Leite G, Rezaie A, Mathur R, et al. Defining Small Intestinal Bacterial Overgrowth by Culture and High Throughput Sequencing. Clin Gastroenterol Hepatol 2024;22(2):259-70. doi: 10.1016/j.cgh.2023.06.001
5. Svedlund J, Sjödin I, Dotevall G. GSRS--a clinical rating scale for gastrointestinal symptoms in patients with irritable bowel syndrome and peptic ulcer disease. Dig Dis Sci 1988;33(2):129-34.
6. Liu ZJ, Wei H, Duan LP, et al. [Clinical features of irritable bowel syndrome with small intestinal bacterial overgrowth and a preliminary study of effectiveness of Rifaximin]. Zhonghua Yi Xue Za Zhi 2016;96(24):1896-902. doi: 10.3760/cma.j.issn.0376-2491.2016.24.005
7. Guo H, Lu S, Zhang J, et al. Berberine and rifaximin effects on small intestinal bacterial overgrowth: Study protocol for an investigator-initiated, double-arm, open-label, randomized clinical trial (BRIEF-SIBO study). Front Pharmacol. 2023;14:1121435. doi:10.3389/fphar.2023.1121435