Oral administration of CXCL12-expressing Limosilactobacillus reuteri improves colitis by local immunomodulatory actions in preclinical models.

Treatments of colitis, inflammation of the intestine, rely on induction of immune suppression associated with systemic adverse events, including recurrent infections. This treatment strategy is specifically problematic in the increasing population of patients with cancer with immune checkpoint inhibitor (ICI)-induced colitis, as immune suppression also interferes with the ICI-treatment response. Thus, there is a need for local-acting treatments that reduce inflammation and enhance intestinal healing. Here, we investigated the effect and safety of bacterial delivery of short-lived immunomodulating chemokines to the inflamed intestine in mice with colitis. Colitis was induced by dextran sulfate sodium (DSS) alone or in combination with ICI (anti-PD1 and anti-CTLA-4), and Limosilactobacillus reuteri R2LC (L. reuteri R2LC) genetically modified to express the chemokine CXCL12-1α (R2LC_CXCL12, emilimogene sigulactibac) was given perorally. In addition, the pharmacology and safety of the formulated drug candidate, ILP100-Oral, were evaluated in rabbits. Peroral CXCL12-producing L. reuteri R2LC significantly improved colitis symptoms already after 2 days in mice with overt DSS and ICI-induced colitis, which in benchmarking experiments was demonstrated to be superior to treatments with anti-TNF-α, anti-α4ß7, and corticosteroids. The mechanism of action involved chemokine delivery to Peyer's patches (PPs), confirmed by local CXCR4 signaling, and increased numbers of colonic, regulatory immune cells expressing IL-10 and TGF-ß1. No systemic exposure or engraftment could be detected in mice, and product feasibility, pharmacology, and safety were confirmed in rabbits. In conclusion, peroral CXCL12-producing L. reuteri R2LC efficiently ameliorates colitis, enhances mucosal healing, and has a favorable safety profile.NEW & NOTEWORTHY Colitis symptoms are efficiently reduced by peroral administration of probiotic bacteria genetically modified to deliver CXCL12 locally to the inflamed intestine in several mouse models.

Engineered bacteria to accelerate wound healing: an adaptive, randomised, double-blind, placebo-controlled, first-in-human phase 1 trial.

Background: Impaired wound healing is a growing medical problem and very few approved drugs with documented clinical efficacy are available. CXCL12-expressing lactic acid bacteria, Limosilactobacillus reuteri (ILP100-Topical), has been demonstrated to accelerate wound healing in controlled preclinical models. In this first-in-human study, the primary objective was to determine safety and tolerability of the drug candidate ILP100-Topical, while secondary objectives included assessments of clinical and biologic effects on wound healing by traditionally accepted methods and explorative and traceable assessments. Methods: SITU-SAFE is an adaptive, randomised, double-blind, placebo-controlled, first-in-human phase 1 trial (EudraCT 2019-000680-24) consisting of a single (SAD) and a multiple ascending dose (MAD) part of three dose cohorts each. The study was performed at the Phase 1 Unit, Uppsala University Hospital, Uppsala, Sweden. Data in this article were collected between Sep 20th, 2019 and Oct 20th 2021. In total 240 wounds were induced on the upper arms in 36 healthy volunteers. SAD: 12 participants, 4 wounds (2/arm), MAD: 24 participants, 8 wounds (4/arm). Wounds in each participant were randomised to treatment with placebo/saline or ILP100-Topical. Findings: In all individuals and doses, ILP100-Topical was safe and well-tolerated with no systemic exposure. A combined cohort analysis showed a significantly larger proportion of healed wounds (p = 0.020) on Day 32 by multi-dosing of ILP100-Topical when compared to saline/placebo (76% (73/96) and 59% (57/96) healed wounds, respectively). In addition, time to first registered healing was shortened by 6 days on average, and by 10 days at highest dose. ILP100-Topical increased the density of CXCL12+ cells in the wounds and local wound blood perfusion. Interpretation: The favourable safety profile and observed effects on wound healing support continued clinical development of ILP100-Topical for the treatment of complicated wounds in patients. Funding: Ilya Pharma AB (Sponsor), H2020 SME Instrument Phase II (#804438), Knut and Alice Wallenberg foundation.

Accelerated Wound Healing in Minipigs by On-Site Production and Delivery of CXCL12 by Transformed Lactic Acid Bacteria.

Non-healing wounds are a growing medical problem and result in considerable suffering. The lack of pharmaceutical treatment options reflects the multistep wound healing process, and the complexity of both translation and assessment of treatment efficacy. We previously demonstrated accelerated healing of full-thickness wounds in mice following topical application of the probiotic bacteria Limosilactobacillus reuteri R2LC transformed to express CXCL12. In this study, safety and biological effects of a freeze-dried formulation of CXCL12-producing L. reuteri (ILP100) were investigated in induced full-thickness wounds in minipigs, and different wound healing evaluation methods (macroscopic, planimetry, 2D-photographs, 3D-scanning, ultrasound) were compared. We found that treatment with ILP100 was safe and accelerated healing, as granulation tissue filled wound cavities 1 day faster in treated compared to untreated/placebo-treated wounds. Furthermore, evaluation using planimetry resulted in 1.5 days faster healing than using 2D photographs of the same wounds, whereas the areas measured using 2D photographs were smaller compared to those obtained from 3D scans accounting for surface curvatures, whereas ultrasound imaging enabled detailed detection of thin epithelial layers. In conclusion, topical administration of the drug candidate ILP100 warrants further clinical development as it was proven to be safe and to accelerate healing using different evaluation methods in minipigs.