Clinical translation of anti-inflammatory effects of Prevotella histicola in Th1, Th2, and Th17 inflammation

Introduction

EDP1815 is a non-colonizing pharmaceutical preparation of a single stain of Prevotella histicola isolated from the duodenum of a human donor. We report here preclinical and clinical studies showing that the action of EDP1815, an orally delivered and gut restricted single strain of commensal bacteria can regulate inflammatory responses throughout the body.

Methods

Supported by evidence for anti-inflammatory activity in three preclinical mouse models of Th1-, TH2-, and Th17-mediated inflammation, EDP1815 was tested clinically in three Phase 1b studies in patients with psoriasis, patients with atopic dermatitis, and healthy volunteers in a KLH skin challenge model.

Results

Preclinically, EDP1815 was efficacious in all three mouse models of inflammation, showing reduction in skin inflammation as well as related tissue cytokines. In the Phase 1b studies, EDP1815 was found to be well tolerated by participants, with a safety profile comparable to placebo, including no severe or consistent side-effects reported, and no evidence of immunosuppression with no opportunistic infection occurring in these studies. In psoriasis patients, signs of clinical efficacy were seen after 4 weeks of treatment, which continued beyond the treatment period in the higher-dose cohort. In atopic dermatitis patients, improvements were seen throughout the key physician-and patient-reported outcomes. In a healthy-volunteer study of a KLH-induced skin inflammatory response, consistent anti-inflammatory effects were seen in two cohorts through imaging-based measures of skin inflammation.

Discussion

This is the first report demonstrating clinical effects from targeting peripheral inflammation with a non-colonizing gut-restricted single strain of commensal bacteria, providing proof of concept for a new class of medicines. These clinical effects occur without systemic exposure of EDP1815 or modification of the resident gut microbiota, and with placebo-like safety and tolerability. The breadth of these clinical effects of EDP1815, combined with its excellent safety and tolerability profile and oral administration, suggests the potential for a new type of effective, safe, oral, and accessible anti-inflammatory medicine to treat the wide range of diseases driven by inflammation.Clinical Trial Registration: EudraCT # 2018-002807-32; EudraCT # 2018-002807-32; NL8676; https://clinicaltrials.gov/ct2/show/NCT03733353; http://www.trialregister.nl.

Direct infant ultraviolet light exposure is associated with eczema and immune development: a critical appraisal

AIM

Rueter et al. aimed to 'determine the effects of early postnatal vitamin D supplementation on infant eczema and immune development'.

SETTING AND DESIGN

This was a double-blind randomized placebo-controlled trial with an additional nonrandomized exploratory analysis on the effects of ultraviolet (UV) exposure led from a hospital setting.

STUDY EXPOSURE

Vitamin D (400 iU daily) drops or placebo drops (coconut and palm kernel oil) were allocated randomly to 195 infants born to families with a first-degree relative with atopic disease. Eighty-six of these infants were allocated personal UV dosimeters in a nonrandomized fashion to measure UV light (290-380 nm) exposure until 3 months of age.

OUTCOMES

Eczema and wheeze were assessed at 3 and 6 months, and 25 immune function markers were assessed at 6 months of age. Infant vitamin D levels and immune functions were measured at 6 months of age.

RESULTS

Although vitamin D levels were significantly greater in infants in the intervention group than in those in the placebo group at 3 and 6 months of age, there was no difference in eczema between groups at either time point (10·0% vs. 6·7% at 3 months and 21·8 vs. 19·3% at 6 months for the vitamin D and placebo groups, respectively). In the subset of infants given a dosimeter, those with eczema had less UV light exposure (median 555 J m^-2 ) than infants who did not develop eczema (median 998 J m^-2 ). Across the 25 immune functions, UV light exposure was inversely correlated with interleukin-2, granulocyte macrophage colony-stimulating factor and eotaxin production by Toll-like receptor ligands.

CONCLUSIONS

Vitamin D supplementation in high-risk infants increased vitamin D levels but did not reduce eczema. Exploratory post-hoc analyses in a nonrandomized subset showed an association between greater direct UV light exposure and reduction of eczema. The authors claim that their 'findings indicate that UV light exposure appears more beneficial than vitamin D supplementation as an allergy prevention strategy in early life'.

Lesson of the month 2: Cauda equina in Cushing's syndrome

We present the case of a 34-year old woman who initially presented with obesity and back pain. She was eventually diagnosed with Cushing's syndrome secondary to an adrenocortical carcinoma that had metastasised to her spine, causing cauda equina compression. The delays in reaching the correct diagnosis caused significant morbidity and exemplify the pitfalls of premature closing, a common cognitive error in diagnostic reasoning.

Pseudomonas aeruginosa meningitis/ventriculitis in a UK tertiary referral hospital

BACKGROUND

Pseudomonas aeruginosa is a rare cause of meningitis and ventriculitis but is generally associated with significant morbidity and mortality.

AIM

We sought to determine the epidemiology, risk factors and outcome of meningitis and ventriculitis due to P. aeruginosa at our institution in order to inform preventive strategies and treatment guidelines.

METHODS

Retrospective study of all patients with a positive cerebrospinal fluid (CSF) culture admitted to a tertiary care hospital over 18 years. Clinical details, demographic, microbiological and antibiotic data were obtained from laboratory and medical records.

RESULTS

Twenty-four episodes occurred in 21 patients over 18 years. Pyrexia (75%), fluctuating mental status (50%) and headache (41%) were the most frequent presenting symptoms. Nineteen of the 21 patients had previously undergone a neurosurgical procedure and seven had extra-ventricular devices in situ. Twelve (57%) patients had P. aeruginosa isolated from another site prior to their episode. Most (89%) CSF samples demonstrated a neutrophilia; the CSF protein, when measured, was raised in all cases. Gram-negative bacilli were visible on CSF microscopy in only three isolates. There were relatively low rates of resistance to most antimicrobials tested and combination treatment of intravenous with intrathecal antibiotics was often used. No patients died within 28 days.

CONCLUSION

Pseudomonas aeruginosa meningitis and ventriculitis are predominantly nosocomial and related to prior neurosurgery. It can be difficult to diagnose as CSF Gram-film and meningism are insensitive markers. Appropriate empirical treatment, neurosurgical prophylaxis and surveillance can aid in managing this infection.