Introduction

Celiac disease (CeD) is triggered by gluten peptides that bind to HLA-DQ2 or -DQ8 in the small intestine leading to gluten specific Th1 T cell expansion and villous atrophy. The oral transglutaminase 2 inhibitor Zed1227 blocks the deamidation of gliadin peptides, a prerequisite for effective gliadin antigen presentation. The CEC-3 clinical trial demonstrated that Zed1227 effectively prevented mucosal damage in 160 CeD patients in remission challenged with 3 g gluten daily for 6 weeks (Schuppan D et al, NEJM 2021).

Aims & Methods

We analyzed regulatory T cell (Treg) gene expression pre and post gluten challenge in the 100 mg/d Zed1227 vs placebo treated patients using RNAseq from the patients’ small intestinal biopsies (Dotsenko V et al, Nat Immunol 2024). We focused on genes of Treg subtypes and related cells. Subanalysis was performed via different gene set enrichments for Treg subsets, regulatory pathways and cell types. Genes that were enhanced in favorable vs unfavorable villous height to crypt depth (V/C) ratio outcomes, also after placebo treatment, were analyzed. We further analyzed pre-disposing genes before challenge, favoring a beneficial or negative post challenge V/C outcome.

Results

93% of the top 100 most significant regulatory genes were upregulated in Zed1227-treated patients compared to those treated with a placebo. These regulatory genes included TGF-beta signaling genes such as Smad7 and MERTK, cholesterol- and fatty acid related genes, such as ACAT1 and NPC1L1, specific autophagy/apoptosis related genes such as VPS35, SQSTM1, BMF, and inhibitory genes like SOCS2. Zed1227 treated patient samples with a maintained post challenge V/C ratio showed evidence for upregulated iTreg genes. Interestingly, Treg genes from placebo-treated subjects were upregulated in correlation with better inflammatory control under gluten challenge compared to worse control.
Moreover, in pre-challenge duodenal samples we identified protective genes that help maintain tolerance during gluten challenge, as reflected by a better post challenge V/C ratio. Examples are ubiquitin ligase RNF167, BAD, FOXN3, BAG1 and CLAUDIN15, whereas other genes like IRF9, CD96 and HLA-/TAP1 were predictive of a more pronounced V/C ratio decline after gluten exposure.

Conclusion

Our data derived from superbly analyzed pre- and post challenge duodenal biopsies demonstrate an active anti-inflammatory immune modulation, largely Treg cell mediated, in CeD in patients prior to and during gluten challenge. Zed1227 treatment potently activates this regulatory response. The balance of several beneficial vs detrimental predisposing Treg-related genes may play a causative role in the variable sensitivity of CeD patients to gluten exposure. Our data support future Treg based therapies to attenuate inflammation in CeD and other (intestinal) autoimmune diseases.

References

Schuppan, D., Mäki, M., Lundin, K. E. A., Isola, J., Friesing-Sosnik, T., Taavela, J., Popp, A., Koskenpato, J., Langhorst, J., Hovde, Ø., Lähdeaho, M. L., Fusco, S., Schumann, M., Török, H. P., Kupcinskas, J., Zopf, Y., Lohse, A. W., Scheinin, M., Kull, K., Biedermann, L., … CEC-3 Trial Group (2021). A Randomized Trial of a Transglutaminase 2 Inhibitor for Celiac Disease. The New England journal of medicine, 385(1), 35–45. https://doi.org/10.1056/NEJMoa2032441
Dotsenko, V., Tewes, B., Hils, M., Pasternack, R., Isola, J., Taavela, J., Popp, A., Sarin, J., Huhtala, H., Hiltunen, P., Zimmermann, T., Mohrbacher, R., Greinwald, R., Lundin, K. E. A., Schuppan, D., Mäki, M., Viiri, K., & CEC-3 Investigators (2024). Transcriptomic analysis of intestine following administration of a transglutaminase 2 inhibitor to prevent gluten-induced intestinal damage in celiac disease. Nature immunology, 25(7), 1218–1230. https://doi.org/10.1038/s41590-024-01867-0

Disclosure

V.D. and K.V. received funding from Dr. Falk Pharma to Tampere University to conduct the study. B.T., T.Z., R.M. and R.G. are employees of Dr. Falk Pharma. The data presented here are the subject of patent applications EP24173619.8 and EP24173615.6 filed by Dr. Falk Pharma, and B.T., T.Z., R.M., R.G., V.D. and K.V. are inventors on these applications. M.H. and R.P. are employees of Zedira. J.T. is a consultant for Jilab Oy and Dr. Falk Pharma. K.E.A.L. is a consultant for Amyra, Bioniz Pharmaceuticals, Chugai Pharmaceutical, Dr. Falk Pharma, Itrexon Actobios, TOPAS Therapeutics and Takeda California. D.S. is the data and safety monitor for Boehringer Ingelheim (Phil.) and is a consultant for the Dr. Falk Pharma, Takeda, Immunic, Sanofi and TOPAS Therapeutics. J.I. is the owner of Jilab Oy. M.M. is the founder, owner and Chair of the Board of Maki HealthTech (MHT). MHT receives Management/Advisory Affiliation fees from Dr. Falk Pharma and other funding not related to the research from Topas Therapeutics, Calypso Biotech, Vaccitech, ImmunogenX, Equillium and Immunic. MHT holds patents (patent number 7361480 (United States) and European Patent Office Number 1390753) licensed to Labsystems Diagnostics from where MHT receives royalties via Tampere University Hospital. All other authors declare no competing interests.

Introduction

Complex perianal fistulas represent one of the most challenging manifestations of Crohn’s disease. Combined surgical and medical therapy with biologic drugs represents today the first-line treatment option, but its efficacy does not exceed 60% in terms of healing. Recently, new therapeutic approaches, such as autologous microfragmented adipose tissue (M-Fat) injection, have shown promising results. Indeed, a recent non-profit prospective pilot study on 15 patients has demonstrated that the local injection of M-Fat is a safe and promising “rescue therapy” for patients with multiresistant complex fistulizing Crohn’s disease (PCD), with a 66.7% rate of combined remission in such difficult patients. It has to be highlighted that the M-Fat injection is minimally invasive, with less risk of sphincteric damage and can be carried out in day-surgery setting.

Aims & Methods

The primary aim of this multicentre double-blind randomized controlled trial (ATTIC) is to evaluate the efficacy of the infiltration of M-Fat in the healing of perianal complex fistulas not-responding to treatment with biologics. Consecutive patients referring to the 6 investigation Centers for surgical treatment of persistent complex fistulizing PCD refractory to biosurgical approach were assessed for eligibility. After baseline pelvic magnetic resonance imaging, those included were submitted to surgical drainage with “cone-like” fistulectomy, and then randomized to receive a 15 to 20 cc local injection, at the internal orifice level and along fistula tracts, of M-Fat obtained by a lipoaspiration and processed with an enzyme-free technology (treatment group), or a suture placement and injection of 15 cc of saline solution at the internal orifice (control group). Clinical follow-up were conducted at 2, 4, 8, 12, and 24 weeks; at 24 weeks after surgery, pelvic magnetic resonance was obtained. Success was defined as “combined remission”, combination of clinical (absence of drainage upon gentle finger compression) and radiological healing (absence of residual collections > 3 mm). Clinical remission was defined as clinical healing of all external openings not confirmed at radiological assessment.

Results

An overall 92 patients were screened, and 66 (33 per group) completed the 24-week follow-up. A statistically significant difference in favour of the treatment group in terms of combined remission emerged at the primary endpoint at 24-week follow-up (control group, 18.18%; treatment group: 57.58%; p = 0.0020). No significant differences in clinical outcome measures were encountered at any of the other follow-up points. No significant differences emerged between the groups in terms of recurrence rate, complication rate, and number of adverse events. Clinical remission was 63.64% in the treatment group compared to 51.52% in the control group with no statistically significant difference (p > 0.05).

Conclusion

This multicentre double-blind randomized controlled trial demonstrates that the intraoperative injection of M-Fat, associated with surgical complete drainage of perianal sepsis, is safe, effective, and reproducible in healing complex multirefractory perianal Crohn's disease, while improving the quality of life and significantly reducing the risk of definitive oostomy.