ARA 290, a nonerythropoietic peptide engineered from erythropoietin, improves metabolic control and neuropathic symptoms in patients with type 2 diabetes.

Although erythropoietin ameliorates experimental type 2 diabetes with neuropathy, serious side effects limit its potential clinical use. ARA 290, a nonhematopoietic peptide designed from the structure of erythropoietin, interacts selectively with the innate repair receptor that mediates tissue protection. ARA 290 has shown efficacy in preclinical and clinical studies of metabolic control and neuropathy. To evaluate the potential activity of ARA 290 in type 2 diabetes and painful neuropathy, subjects were enrolled in this phase 2 study. ARA 290 (4 mg) or placebo were self-administered subcutaneously daily for 28 d and the subjects followed for an additional month without further treatment. No potential safety issues were identified. Subjects receiving ARA 290 exhibited an improvement in hemoglobin A(1c) (Hb A(1c)) and lipid profiles throughout the 56 d observation period. Neuropathic symptoms as assessed by the PainDetect questionnaire improved significantly in the ARA 290 group. Mean corneal nerve fiber density (CNFD) was reduced significantly compared with normal controls and subjects with a mean CNFD >1 standard deviation from normal showed a significant increase in CNFD compared with no change in the placebo group. These observations suggest that ARA 290 may benefit both metabolic control and neuropathy in subjects with type 2 diabetes and deserves continued clinical evaluation.

A Phase 2 Clinical Trial on the Use of Cibinetide for the Treatment of Diabetic Macular Edema.

PURPOSE: Evaluating the effects of cibinetide in diabetic macular edema (DME). METHODS: Phase 2 trial. Naïve patients with >400 µm central retinal thickness (CRT) DME in one/both eyes were recruited (May 2016-April 2017) at the Belfast Health and Social Care Trust. The study eye was that with best vision and lowest CRT. Patients self-administered cibinetide 4 mg/day subcutaneously for 12 weeks. Primary and secondary outcomes: mean change from baseline to week 12 in best corrected visual acuity (BCVA), CRT, central retinal sensitivity, tear production, patient-reported outcomes, adverse events and antibodies to cibinetide. Descriptive statistics were used; exploratory analyses focused on non-study eyes, diabetic control, serum cytokines and albuminuria. RESULTS: Nine patients were recruited; eight completed the study. There was no improvement in mean change baseline-week 12 in BCVA (-2.9 + 5.0), CRT (10 + 94.6 microns), central retinal sensitivity (-0.53 + 1.9 dB) or tear production (-0.13 + 7.7 mm), but there was an improvement in National Eye Institute Visual Function Questionnaire (NEI VFQ-25) composite scores (2.7 + 3.1). Some participants experienced improvements in CRT, tear production, diabetic control and albuminuria. No serious adverse events/reactions or anti-cibinetide antibodies were seen. CONCLUSIONS: The cibinetide 12-week course was safe. Improvements in NEI VFQ-25 scores, CRT, tear production, diabetic control and albuminuria, observed in some participants, warrant further investigation. TRIAL REGISTRATION: EudraCT number: 2015-001940-12. ISRCTN16962255-registration date 25.06.15.

Ambient air particulate matter exposure and tissue factor expression in atherosclerosis.

Recent studies have suggested a link between inhaled particulate matter (PM) exposure and atherogenesis. We investigated tissue factor (TF) expression with ambient fine particulate matter (diameter < 2.5 microm, PM(2.5)) exposure and in response to in vitro exposure to fine and ultrafine PM in cultured human bronchial epithelial cells, vascular smooth muscle cells (hSMCs), and monocytes. ApoE-/- mice, fed with normal chow (NC) or high-fat chow (HFC), were exposed to concentrated PM(2.5) or filtered air (FA) for 6 mo (6 h/day, 5 day/wk, n = 28). Following in vivo ultrasound bio-microscopy (UBM) assessment of plaque area, macrophage infiltration (CD68) and TF expression in the aorta were quantified. Cultured cells were incubated with size-fractionated PM from cascade impactors, or with standard reference PM material (SRM, number 1649a) and assayed for TF protein, mRNA, and activity. UBM-derived plaque areas were 7 +/- 1% larger in the PM(2.5)-HFC than the FA-HFC group (p = .04), but not significantly different between the PM(2.5)-NC and FA-NC groups (p = .07). Immunohistochemistry revealed increased TF (15 +/- 3% vs. 8 +/- 2%, p < .01) and macrophage infiltration (19 +/- 2% vs. 14 +/- 3%, p < .01) in the plaques of PM(2.5)-HFC compared with FA-HFC groups. Impactor-collected PM(2.5) and ultrafine particles consistently increased TF protein in bronchial epithelial cells, monocytes, and hSMCs. TF mRNA expression increased rapidly (within 1 h) in response to SRM PM. We conclude that in vivo and in vitro exposure to ambient air PM(2.5) induces TF expression.

Cibinetide Improves Corneal Nerve Fiber Abundance in Patients With Sarcoidosis-Associated Small Nerve Fiber Loss and Neuropathic Pain.

Purpose: Sarcoidosis frequently is complicated by small nerve fiber loss (SNFL), which can be quantified using corneal confocal microscopy (CCM). Prior studies suggest that the innate repair receptor agonist cibinetide reverses corneal nerve loss. This phase 2b, 28-day, randomized trial of 64 subjects with sarcoid-associated SNFL and neuropathic pain assessed the effect of cibinetide on corneal nerve fiber area (CNFA) and regenerating intraepidermal fibers (GAP-43+) as surrogate endpoints for disease modification, pain severity, and functional capacity (6-minute walk test [6MWT]). Methods: Cibinetide (1, 4, or 8 mg/day) was compared to placebo. The primary study endpoint was a change in CNFA at 28 days. Results: The placebo-corrected mean change from baseline CNFA (µm2) at day 28 was 109 (95% confidence interval [CI], -429, 647), 697 (159, 1236; P = 0.012), and 431 (-130, 992) in the 1, 4, and 8 mg groups, respectively. Intraepidermal GAP-43+ fibers increased in the 4 mg group (P = 0.035). Further, changes in CNFA correlated with changes in GAP-43+ (ρ = 0.575; P = 0.025) and 6MWT (ρ = 0.645; P = 0.009). Pain improved significantly in all groups, with subjects having moderate-severe pain reporting a clinically meaningful placebo-corrected decrease in pain intensity in the 4 mg group (P = 0.157). Conclusions: Cibinetide significantly increased small nerve fiber abundance in the cornea and skin, consistent with a disease modifying effect. The relationships between CNFA and other clinical measures of disease support its use as a surrogate endpoint to assess potential disease modifying therapies for neuropathy.