Introduction
Inflammatory cells and cytokines play an instrumental role in the pathogenesis and disease course of ulcerative colitis (UC) and are thus accepted therapeutic targets. NX-13 is a first-in-class, orally active, once-daily, gut-selective NLRX1 agonist in development for UC. NLRX1 is a mitochondrial associated protein with a novel, bimodal, immunometabolic mechanism which upregulates mitochondrial metabolism, reduces oxidative stress, and decreases pro-inflammatory cell differentiation and cytokine release broadly in mouse models of IBD1. NX-13 was well tolerated and showed gut selectivity with low systemic drug exposure in Phase 1 studies reported previously2,3. We now present data from the phase 1b study describing changes in tissue cytokine levels and related to clinical response.
Aims & Methods
In this double-blind phase 1B trial (NCT04862741)3, 36 patients with active UC (Total Mayo Score 4-10; Mayo endoscopic subscore 2-3) were randomly assigned to NX-13 250mg Immediate Release (IR), 500mg IR, 500mg Delayed Release (DR) or Placebo QD for 4 weeks. Protein levels of IFNγ, IL-10, IL-12(p40), IL-17, IL-4, IL-6, IL-8, MCP1, and TNFα in colonic tissue from NX-13 treated patients collected at screening (baseline) and week 4 of treatment were determined by Human Cytokine/Chemokine Panel – Immunology Multiplex Assay (Millipore Sigma) normalized to total protein concentrations. Patients from all NX-13 dose groups with paired baseline and week 4 samples (n=18) were included in this analysis. Mann-Whitney U testing was used for comparisons between responders (Resp) and non-responders (NR).
Results
Baseline cytokines levels were not different between Resp (change from baseline of at least –3, or –30% in total Mayo Score) and NR. NX-13 treatment resulted in a decrease of multiple proinflammatory cytokines at week 4 compared to baseline in most patients, and especially in Resp. compared to NR at week 4 (Table 1). Primarily, the reduction (% change from baseline) of Th1 cytokines IL-12(p40) and IFNγ was greater in NX-13 treated patients with clinical response compared to NR, resulting in significantly lower values in Resp compared to NR at the end of the 4-week study. Similarly, IL-6 also tended to be lower among Resp. after 4 weeks of treatment with NX-13. Additionally, Th2 cytokine IL-4 values were significantly lower after 4 weeks of NX-13 in patients in clinical response compared to NR. Myeloid cell recruitment may also have been affected by cytokine changes induced by NX-13 as IL-8 and MCP levels were lower in clinical Resp. Reduced myeloid cell recruitment is consistent with higher levels of histologic remission in NX-13 treated patients3.
| | | Mean % CFB (95% CI) | Mean Value Week 4 / End of Study (95% CI) |
| Cytokine | Primary Function | NR (n=7) | Resp (n=11) | p= | NR (n=7) | Resp (n=11) | p= |
| IL-12 (p40) | Th1 | 199 (-5.83-404) | -2.42 (-45.0-40.1) | 0.03* | 12.3 (1.2-23.5) | 2.0 (1.2-2.9) | 0.005** |
| IFNg | Th1 | 1208 (-837-3253) | 53.4 (-164-271) | 0.004** | 143.4 (-135.6-422.3) | 6.3 (0.03-12.6) | 0.01* |
| IL-6 | Th1 | 3864 (-3044-10771) | 63.7 (-126-253) | ns | 120.4 (-17.5-258.4) | 4.5 (1.4-7.6) | 0.06# |
| IL-4 | Th2 | 390 (-262-1041) | -13.7 (-61.9-34.4) | ns | 31.0 (3.7-58.3) | 3.7 (1.7-5.6) | 0.01* |
| IL-8 | Chemoattractant | 1207 (-648-3063) | 568 (-817-1954) | 0.07# | 204.3 (-0.1-408.6) | 29.4 (7.4-51.4) | 0.06# |
| MCP-1 | Chemoattractant | 968 (-769-2726) | 7483 (-9258-24225) | ns | 1684.2 (454.9-2913.4) | 475.0 (145.6-804.4) | 0.05# |
| CFB = Change from Baseline; NR= Clinical Non-Responder; Resp = Clinical Responder defined as CFB of at least –3, or –30% in total Mayo Score; **p≤0.005, *p≤0.05, #p≤0.10. ns p>0.10 by Mann-Whitney U testing. |
Conclusion
Broad changes in tissue cytokine expression were specifically observed in patients that responded to NX-13- after 4 weeks of treatment, compared to non-responders. These changes mirror those seen in preclinical mouse colitis models where a broad array of cytokines is reduced1. The early onset of cytokine shifts associated with clinical response to NX-13 at week 4 is notable and will be assessed in the ongoing phase 2 NEXUS study in patients with moderate to severe UC (NCT05785715).
References
1Leber, et al. J Immunol 203(12); 2Leber, et al. UEGW J 9(Supp); 3Verstockt, et al. JCC epub 11NOV2023
Disclosure
BS has received grant support from Pfizer (to institution); served as a consultant (served as a representative of Charité) for AbbVie, Arena, BMS, Boehringer, Celgene, Endpoint Health, Falk, Galapagos, Janssen, Landos, Lilly, Pfizer, PredictImmune, and Takeda; and has received speaker’s fees (served as a representative of Charité) from AbbVie, CED Service GmbH, Falk, Ferring, Galapagos, Janssen, Lilly, Pfizer, and Takeda; support for attending meetings/travel from Falk; and served as president of ECCO. | SV has received grants from AbbVie, J&J, Pfizer, Takeda, and Galapagos; consulting and/or speaking fees from 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, and Zealand Pharma. | AY reports consulting fees from Takeda, Prometheus Labs, Arena Pharmaceuticals, and Bristol Myers Squibb; and speaker bureau fees from Bristol Myers Squibb. | SS has received personal fees from AbbVie, Amgen, Arena Pharmaceuticals, Bristol Myers Squibb, Boehringer Ingelheim, Celltrion, Dr Falk Pharma, Ferring, Fresenius, Galapagos, Genentech, GSK, Gilead, I-MAB Biopharma, Janssen, Lilly, Merck, Novartis-Sandoz, Pfizer, Protagonist, Takeda, and Theravance. | SD reports consultancy fees from AbbVie, Alimentiv, Allergan, Amgen, AstraZeneca, Athos Therapeutics, Biogen, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Celltrion, Dr Falk Pharma, Eli Lilly, Enthera, Ferring Pharmaceuticals Inc., Gilead, Hospira, Inotrem, Janssen, Johnson & Johnson, MSD, Mundipharma, Mylan, Pfizer, Roche, Sandoz, Sublimity Therapeutics, Takeda, TiGenix, UCB Inc., and Vifor; he reports lecture fees from Abbvie, Amgen, Ferring Pharmaceuticals Inc., Gilead, Janssen, Mylan, Pfizer, and Takeda. | RM is an employee of Landos. | FC is an employee of Landos. | BV has received grants from Abbvie, Biora Therapeutics, Landos, Pfizer, Sossei Heptares, and Takeda; Speaker’s fees from Abbvie, Biogen, Bristol Myers Squibb, Celltrion, Chiesi, Falk, Ferring, Galapagos, Janssen, MSD, Pfizer, R-Biopharm, Takeda, Truvion and Viatris. Consultancy fees from Abbvie, Alimentiv, Applied Strategic, Atheneum, Biora Therapeutics, Bristol Myers Squibb, Galapagos, Guidepoint, Landos, Mylan, Inotrem, Ipsos, Janssen, Progenity, Sandoz, Sosei Heptares, Takeda, Tillots Pharma and Viatris. | MCD reports consulting fees from AbbVie, Arena, Bristol Myers Squibb, Celgene, Eli Lilly, Genentech, Gilead, Janssen, Pfizer, Prometheus Labs, and Takeda; and is founder and a shareholder of Trellus Health.
