Introduction

Biologic therapies such as anti-TNF-alpha agents (infliximab, adalimumab), interleukin modulators, and gut-selective integrin antagonists like vedolizumab have significantly improved outcomes in inflammatory bowel disease (IBD), leading to enduring remission, better quality of life, and reduced surgical intervention and hospitalizations. However, many patients may eventually lose response, often due to factors like the formation of anti-drug antibodies, altered drug metabolism, or individual patient characteristics. Dose escalation—by increasing dosage or reducing intervals—is commonly used to counteract this loss, especially for anti-TNF therapies guided by therapeutic drug monitoring. Vedolizumab poses a greater challenge in this regard due to the lack of standardized monitoring protocols. We aimed to investigate the effectiveness of dose-escalated infliximab, adalimumab, and vedolizumab in IBD patients who worsened after initial response, evaluating outcomes such as treatment persistence and clinical remission, to guide more personalized, cost-effective treatment strategies.

Aims & Methods

We conducted a retrospective analysis of IBD patients who underwent Infliximab (IFX), vedolizumab, or adalimumab (ADA) therapy dose escalation between 2020-2024 at a tertiary IBD centre. Primary outcomes included clinical remission using disease activity scores (Simple Clinical Colitis Activity/SCCAI Index for UC, Harvey-Bradshaw Index/HBI for CD), biochemical markers (CRP, faecal calprotectin) and treatment persistence, evaluated at 3-12 months, 12 months, and annually up to 36 months post-escalation.

Results

A total of 155 patients (median age 31 years, 46% female) were included, of which 89 patients (57%) were prescribed dose-escalated IFX, 48 patients (31%) were prescribed dose-escalated ADA and 18 patients (12%) were prescribed dose-escalated Vedolizumab. Of those included, 118 patients (76%) had Crohn’s disease, 36 patients (23%) had ulcerative colitis (UC) and 1 patient (1%) had indeterminate disease. Indications for dose escalation included secondary loss of response (SLOR) (105/155; 68%) and/or low drug levels (65/155; 42%). Dose-escalated IFX led to significant improvements in disease activity scores at 3 months (HBI: p=0.002; SCCAI: p=0.0003). Improvement in SCCAI was maintained at 12 months (p=0.00007), 2 years (p=0.0008) and 3 years (p=0.025). Improvement in HBI was maintained at 2 years (p=0.01) and 3 years (p=0.049). Significant improvement in CRP following dose-escalated IFX was reported at 3 months (p=0.011), 12 months (p=0.004), 2 years (p=0.006) and 3 years (p=0.03). Dose-escalated ADA led to a significant improvement in HBI at 3 months (p=0.023). This improvement was maintained at 12 months (p=0.005) and 2 years (p=0.008). Early improvement in faecal calprotectin was reported at 3 months (p=0.046). Significant initial improvement in SCCAI following dose-escalated Vedolizumab was reported at 3 months (p=0.043). This improvement was not maintained at any further follow-up points (p>0.05). Minor adverse events were reported in 3 patients receiving dose escalated ADA and in 6 patients receiving dose escalated IFX.

Conclusion

Our study demonstrates that biologic dose escalation is an effective and safe mechanism to recapture clinical remission, with high rates of treatment persistence.

Introduction

Total retocolectomy with ileal pouch anal anastomosis (IPAA) is the surgical procedure of choice for patients with ulcerative colitis (UC) refractory to clinical treatment and familial adenomatous polyposis (FAP) with many polyps in the rectum. Primary ileitis of the ileal pouch (IP) is one of the most common complications in UC, being rare in FAP. Previous studies have identified an increase in pro-inflammatory cytokines, as well as alterations in the apoptosis and macroautophagy pathways markers in the IP mucosa of UC patients, compared to those with FAP and normal distal ileum (controls). Since autophagy and apoptosis can be modulated by endoplasmic reticulum (ER) stress, we investigated this pathway in IP of UC compared to PAF and controls.

Aims & Methods

The aim was to evaluate the modulation of ER stress in the IP mucosa of UC and FAP patients who underwent IPAA, compared to controls. Thirty-two patients were included, ten in the UC group, twelve in FAP group and ten in the control group. Patients who had undergone ileostomy closure for less than one year and had clinical, histological, or endoscopic evidence of pouchitis were excluded. The patients underwent routine colonoscopy, and biopsies were performed from the IP. For the control group, biopsies were taken from the normal distal ileum. The local Ethics Committee approved the study. The biopsies were processed for RNA extraction and subsequent gene expression analysis using the quantitative PCR (qPCR) technique. The following transcripts were investigated: IRE1 (ERN), PERK (EIF2AK3), ATF6, GRP78 (HSPA5), GRP94 (HSP90B1), ATF3, STC2, DDIT3, DNAJC3, and CALR. Nonparametric tests were used for statistical analysis, with a significance level of p<0.05.

Results

The pouchitis disease activity index (PDAI) was applied to verify the absence of pouchitis, with all patients scoring lower than 7. There was no increase in the transcriptional level of the main ER stress pathway markers (ERE1, PERK, and ATF6) in the IP without pouchitis. However, there was a significantly lower expression of DDIT3 in the UC and FAP groups compared to the control (p≤0.05), which may suggest a deficiency in counterbalance the ER stress activation. On the other hand, concerning the UPR pathway markers, the levels of CALR and HSP90B1 were significantly higher in the IP of UC compared to the respective IP afferent loop (p≤0.05), supporting potential activation of the ER stress in the IP in the UC group. Additionally, the transcriptional level of ATF3 was significantly higher in the PAF group compared to the control (p≤0.05), which may indicate a counter-regulatory mechanism in response to tissue damage, which was not verified in the UC group.

Conclusion

Our findings demonstrated that markers of the unfolded protein response (UPR) signaling pathway, which is activated in response to ER stress, are modulated in the IP mucosa of UC patients, even in the absence of pouchitis. These results may explain the propensity to IP inflammation in UC patients. They may guide the identification of additional molecular pathways contributing to inflammation of the IP and the search for new therapeutic targets.

References

1. Negreiros LMV, Pascoal LB, Genaro LM, et al. Pouchitis: insight into the pathogenesis and clinical aspects. Am J Transl Res. 2022 Jul 15;14(7):4406-4425.
2. Rodrigues BL, Dotti I, Pascoal LB, et al. Endoplasmic Reticulum Stress in Colonic Mucosa of Ulcerative Colitis Patients Is Mediated by PERK and IRE1 Pathway Activation. Mediators Inflamm. 2022 Feb 9;2022:6049500.
3. Paiva NM, Pascoal LB, Negreiros LMV, et al. Ileal pouch of ulcerative colitis and familial adenomatous polyposis patients exhibit modulation of autophagy markers. Sci Rep. 2018 Feb 8;8(1):2619.
4. Qiao D, Zhang Z, Zhang Y, Chen Q, Chen Y, Tang Y, et al. Regulation of Endoplasmic Reticulum Stress-Autophagy: A Potential Therapeutic Target for Ulcerative Colitis. Front Pharmacol. 2021;Volume 12-2021.

Introduction

Guselkumab (GUS), a dual-acting IL-23p19 subunit inhibitor, is highly efficacious in participants (pts) with Crohn’s disease (CD) after intravenous (IV) or subcutaneous (SC) induction followed by SC maintenance. This analysis characterized pharmacokinetics (PK) and exposure-response (E-R) for efficacy and safety of both administration routes and confirmed assumptions for the development of IV and SC induction formulations.

Aims & Methods

GUS efficacy and safety in pts with moderate to severely active CD were evaluated in the phase 2 GALAXI 1 (200, 600, or 1200 mg IV at week [W]0, W4, and W8),¹ phase 3 GALAXI 2 and 3 (200 mg IV at W0, W4, and W8),² and phase 3 GRAVITI studies (400 mg SC at W0, W4, and W8).³ All studies used treat-through designs and the same SC maintenance dose regimens (100 mg q8w or 200 mg q4w). With an estimated ~50% bioavailability of SC GUS, the 2-fold higher SC induction dose was predicted to provide similar overall exposure and noninferior trough concentrations compared with the IV dose.
To characterize GUS PK, a population PK model was used to simulate exposure metrics for IV and SC induction using individual post-hoc PK parameters and actual pt dosages. Relationships between GUS exposure and select efficacy endpoints (clinical response, clinical remission, and endoscopic response) at week 12 were assessed.

Results

SC induction resulted in higher trough serum concentrations (at W12), lower peak serum concentrations, similar average concentrations (W0–W12), and similar area under the concentration-time curves (W0–W12) vs IV induction (Table). Regardless of induction route (IV or SC) or maintenance regimen, GUS serum concentrations reached steady state by W24.
W12 efficacy outcomes were comparable within GUS concentration quartiles after SC vs IV induction. Although pts with higher serum GUS concentrations tended to achieve greater W12 efficacy outcomes, this trend was no longer evident after accounting for a pt’s drug clearance or the half-life of the drug. W48 outcomes were similar in pts who received the same maintenance regimen, regardless of induction dose route. No positive E-R trends were seen between peak concentration and W12 efficacy endpoints; thus, the higher peak concentration observed with IV induction did not seem to improve efficacy. Across concentration quartiles, the incidence of safety events was comparable between pts who received GUS IV or SC induction regimens. No positive associations between serum concentrations and adverse events (infections, serious infections, and serious adverse events) or abnormal liver function tests were observed.

Conclusion

Average serum GUS concentrations and E-R relationships were similar after IV vs SC induction and had no impact on safety, supporting the use of either administration route and induction dose regimen in CD patients.

References

1. Sandborn WJ, et al. Guselkumab for the treatment of Crohn's disease: induction results from the phase 2 GALAXI-1 study. Gastroenterology. 2022; 162(6):1650-1664.e8.
2. Panaccione R, et al. Efficacy and safety of guselkumab therapy in patients with moderately to severely active Crohn’s disease: results of the GALAXI 2 & 3 phase 3 studies. Gastroenterology. 2024; 166 (5 Supplement):1057b.
3. Hart A, et al. Efficacy and safety of guselkumab subcutaneous induction and maintenance in participants with moderately to severely active Crohn's disease: results from the phase 3 GRAVITI study. Gastroenterology. 2025; S0016-5085(25)00522-0.

Disclosure

Geert D’Haens has served as advisor and/or speaker for Abbvie, Abivax, Agomab, Alimentiv, Anaptys Bio, Bristol Meiers Squibb, Boehringer Ingelheim, Celltrion, Eli Lilly, Galapagos, Glaxo Smith Kline, Index Pharmaceuticals, Johnson and Johnson, Merck, Polpharm, Prometheus biosciences, Sanofi, Takeda, Tillotts.
Omoniyi J. Adedokun, Tae Eun Yang, Nat A. Terry, Mobolaji Olurinde, Rian Van Rampelbergh, and Marion L. Vetter are employees of Janssen Research & Development (a Johnson & Johnson Company) and may own company stock/stock options.
Bruce E. Sands reports potential conflicts of interest with AbbVie, Abivax, Adiso Therapeutics, Agomab, Alimentiv, Amgen, AnaptysBio, Arena Pharmaceuticals, Artugen Therapeutics, AstraZeneca, Biora Therapeutics, Boehringer Ingelheim, Boston Pharmaceuticals, Bristol Myers Squibb, Calibr, Celgene, Celltrion, ClostraBio, Equillium, Enthera, Evommune, Ferring, Fresenius Kabi, Galapagos, Genentech (Roche), Gilead Sciences, GlaxoSmithKline, Gossamer Bio, Index Pharmaceuticals, Innovation Pharmaceuticals, Inotrem, Janssen, Kaleido, Kallyope, Lilly, Merck, Microbiotica, Mobius Care, Morphic Therapeutics, MRM Health, Pfizer, Nexus Therapeutics, Nimbus Discovery, Odyssey, Therapeutics, Progenity, Prometheus Biosciences, Prometheus Laboratories, Protagonist Therapeutics, Q32 Bio, Rasayana Therapeutics, Recludix Therapeutics, Reistone Biotherapeutics, Sun Pharma, Surrozen, Target RWE, Takeda, Teva, Theravance Biopharma, TLL Pharmaceutical, TR1X, Union Therapeutics and Ventyx Biosciences.
Silvio Danese reports potential conflicts of interest with AbbVie, Alimentiv, Allergan, Amgen, AstraZeneca, Athos, Biogen, Boehringer Ingelheim, Celgene, Celltrion, Eli Lilly, Enthera, Ferring, Gilead, Hospira, Inotrem, Janssen, Johnson & Johnson, MSD, Mundipharma, Mylan, Pfizer, Roche, Sandoz, Sublimity, Takeda, TiGenix, UCB, and Vifor.
Tadakazu Hisamatsu reports potential conflicts of interest with AbbVie, Bristol Myers Squibb, Daiichi-Sankyo, EA Pharma Co, Ltd., Eli Lilly, Gilead Sciences, Janssen Research & Development, LLC., JIMRO, Kissei Pharmaceutical Co, Ltd., Mitsubishi Tanabe Pharma Corporation, Mochida Pharmaceutical Co., Ltd., Nippon Kayaku Co., Ltd., Pfizer Inc., and Takeda Pharmaceutical Co., Ltd.
Remo Panaccione reports potential conflicts of interest with Abbivax, Abbott, AbbVie, Alimentiv (formerly Robarts), Amgen, 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, Janssen, Merck, Mylan, Novartis, Oppilan Pharma, Organon, Pandion Pharma, Pendopharm, Pfizer, Progenity, Prometheus Biosciences, Protagonist Therapeutics, Roche, Sandoz, Satisfai Health, Shire, Sublimity Therapeutics, Takeda Pharmaceuticals, Theravance Biopharma, Trellus, Viatris, Ventyx, and UCB.