A Randomized, double-blind, dose ranging clinical trial of intravenous FDY-5301 in acute STEMI patients undergoing primary PCI.

BACKGROUND: Ischemia-reperfusion injury remains a major clinical problem in patients with ST-elevation myocardial infarction (STEMI), leading to myocardial damage despite early reperfusion by primary percutaneous coronary intervention (PPCI). There are no effective therapies to limit ischemia-reperfusion injury, which is caused by multiple pathways activated by rapid tissue reoxygenation and the generation of reactive oxygen species (ROS). FDY-5301 contains sodium iodide, a ubiquitous inorganic halide and elemental reducing agent that can act as a catalytic anti-peroxidant. We tested the feasibility, safety and potential utility of FDY-5301 as a treatment to limit ischemia-reperfusion injury, in patients with first-time STEMI undergoing emergency PPCI. METHODS: STEMI patients (n = 120, median 62 years) presenting within 12 h of chest pain onset were randomized at 20 PPCI centers, in a double blind Phase 2 clinical trial, to receive FDY-5301 (0.5, 1.0 or 2.0 mg/kg) or placebo prior to reperfusion, to evaluate the feasibility endpoints. Participants underwent continuous ECG monitoring for 14 days after PPCI to address pre-specified cardiac arrhythmia safety end points and cardiac magnetic resonance imaging (MRI) at 72 h and at 3 months to assess exploratory efficacy end points. RESULTS: Intravenous FDY-5301 was delivered before re-opening of the infarct-related artery in 97% participants and increased plasma iodide levels ~1000-fold within 2 min. There was no significant increase in the primary safety end point of incidence of cardiac arrhythmias of concern. MRI at 3 months revealed median final infarct sizes in placebo vs. 2.0 mg/kg FDY-5301-treated patients of 14.9% vs. 8.5%, and LV ejection fractions of 53.9% vs. 63.2%, respectively, although the study was not powered to detect statistical significance. In patients receiving FDY-5301, there was a significant reduction in the levels of MPO, MMP2 and NTproBNP after PPCI, but no reduction with placebo. CONCLUSIONS: Intravenous FDY-5301, delivered immediately prior to PPCI in acute STEMI, is feasible, safe, and shows potential efficacy. A larger trial is justified to test the effects of FDY-5301 on acute ischemia-reperfusion injury and clinical outcomes. CLINICAL TRIAL REGISTRATION: CT.govNCT03470441; EudraCT 2017-000047-41.

C-terminal provasopressin (copeptin) as a prognostic marker after acute non-ST elevation myocardial infarction: Leicester Acute Myocardial Infarction Peptide II (LAMP II) study.

Copeptin, the 39-amino-acid C-terminal portion of provasopressin, has been shown to be an independent predictor for adverse events following STEMI (ST elevation myocardial infarction). We hypothesized that plasma copeptin was an independent predictor for adverse outcomes following acute NSTEMI (non-STEMI) and evaluated whether copeptin added prognostic information to the GRACE (Global Registry of Acute Coronary Events) score compared with NT-proBNP (N-terminal pro-B-type natriuretic peptide). Plasma copeptin and NT-proBNP were measured in 754 consecutive patients admitted to the hospital with chest pain and diagnosed as having NSTEMI in this prospective observational study. The end point was all-cause mortality at 6 months. Upper median levels of copeptin were strongly associated with all-cause mortality at 6 months. Copeptin was a significant predictor of time to mortality {HR (hazard ratio), 5.98 [95% CI (confidence interval, 3.75-9.53]; P < 0.0005} in univariate analysis and remained a significant predictor in multivariate analysis [HR, 3.03 (05% CI, 1.32-6.98); P = 0.009]. There were no significant differences between the area under ROC (receiver operating characteristic) curves of copeptin, NT-proBNP and the GRACE score. Copeptin improved accuracy of risk classification when used in combination with the GRACE score as determined by net reclassification improvement, whereas NT-proBNP did not. The relative utility of the GRACE score was increased more by copeptin than by NT-proBNP over a wide range of risks. Plasma copeptin is elevated after NSTEMI, and higher levels are associated with worse outcomes. Copeptin used in conjunction with the GRACE score improves risk stratification enabling more accurate identification of high-risk individuals.

Increased free radical production in hypertension due to increased expression of the NADPH oxidase subunit p22(phox) in lymphoblast cell lines.

OBJECTIVES: To confirm increased production of reactive oxygen species (ROS) in hypertension, to demonstrate the source of ROS and to analyse NADPH oxidase subcomponent expression in hypertension. DESIGN: A lymphoblast model was used, as this has previously been used in the study of hypertension and of NADPH oxidase. Chemiluminescence (CL) was chosen to assay ROS production, as it is simple and sensitive. METHODS: Lymphocytes from 12 hypertensive patients (HT), and 12 age- and sex-matched normotensive (NT) subjects, were immortalized. Luminol, isoluminol and Cypridina luciferin analogue (CLA) CL were used to assay ROS production. NADPH oxidase subunits were measured by Western blot analysis. RESULTS: Stimulation with 50 micromol/l arachidonic acid (AA) resulted in increased ROS production in HT cell lines with luminol, CLA and isoluminol CL. Stimulation with 500 nmol/l 12-O-tetradecanoylphorbol-13-acetate (TPA) produced a detectable increase in HT ROS production with luminol and with CLA, whereas there was no significant difference with isoluminol. The ROS production was abolished by diphenyleneiodonium chloride (DPI) but not by rotenone, indicating that a non-mitochondrial flavoprotein such as NADPH oxidase is the source of ROS. Analysis of NADPH oxidase subcomponents revealed an increase in p22(phox) in HT subjects. CONCLUSIONS: We have shown there is increased ROS production in lymphoblasts derived from hypertensive subjects, probably originating from NADPH oxidase. As the ROS production persists in transformed cells, this suggests a genetic predisposition to increased ROS production. Increased expression of p22(phox) in HT lymphoblasts may account for some of the increased ROS.