Cardiovascular Safety and All-Cause Mortality of Methoxy Polyethylene Glycol-Epoetin Beta and Other Erythropoiesis-Stimulating Agents in Anemia of CKD: A Randomized Noninferiority Trial.

BACKGROUND AND OBJECTIVES: Erythropoiesis-stimulating agents correct anemia of CKD but may increase cardiovascular risk. We compared cardiovascular outcomes and all-cause mortality associated with monthly methoxy polyethylene glycol-epoetin beta with those of the shorter-acting agents epoetin alfa/beta and darbepoetin alfa in patients with anemia of CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We conducted a multicenter, open-label, noninferiority trial in which patients were randomized to receive methoxy polyethylene glycol-epoetin beta or reference erythropoiesis-stimulating agents, stratified by maintenance or correction treatment status and C-reactive protein level. The trial had a prespecified noninferiority margin of 1.20 for the hazard ratio (HR) for the primary end point (a composite of all-cause mortality, nonfatal myocardial infarction or stroke, adjudicated by an independent blinded committee). This trial is registered with ClinicalTrials.gov, number NCT00773513. RESULTS: In total, 2818 patients underwent randomization, received methoxy polyethylene glycol-epoetin beta or a reference agent, and were followed for a median of 3.4 years (maximum, 8.4 years). In the modified intention-to-treat analysis, a primary end point event occurred in 640 (45.4%) patients in the methoxy polyethylene glycol-epoetin beta arm, and 644 (45.7%) in the reference arm (HR 1.03; 95% confidence interval [95% CI], 0.93 to 1.15, P=0.004 for noninferiority). All-cause mortality was not different between treatment groups (HR 1.06; 95% CI, 0.94 to 1.19). Results in patient subgroups on dialysis or treated in the correction or maintenance settings were comparable to the primary analysis. CONCLUSIONS: In patients with anemia of CKD, once-monthly methoxy polyethylene glycol-epoetin beta was noninferior to conventional, shorter-acting erythropoiesis-stimulating agents with respect to rates of major adverse cardiovascular events or all-cause mortality.

Intravenous methoxy polyethylene glycol-epoetin beta for haemoglobin control in patients with chronic kidney disease who are on dialysis: a randomised non-inferiority trial (MAXIMA).

BACKGROUND: Conventional treatment with epoetin to manage anaemia in chronic kidney disease needs frequent administrations, changes of dose, and close monitoring of haemoglobin concentrations. We aimed to compare the effectiveness of methoxy polyethylene glycol-epoetin beta, given intravenously at 2-week or 4-week intervals, with epoetin treatment one to three times per week for haemoglobin control in haemodialysis patients. METHODS: We screened 1115 adult patients from 96 centres who had stable chronic renal anaemia and were on dialysis treatment and intravenous maintenance epoetin. We did an open-label, parallel-group, non-inferiority trial to compare two dosing intervals of methoxy polyethylene glycol-epoetin beta with standard epoetin treatment. We established baseline haemoglobin concentration and eligibility over a 4-week run-in period. 223 patients were randomly assigned to receive methoxy polyethylene glycol-epoetin beta every 2 weeks, and 224 to receive it every 4 weeks. The initial dose was based on the average epoetin dose given during the week before the switch. The primary endpoint was change in haemoglobin concentration between baseline and the assessment period. We analysed patients both by intention to treat and per protocol. This study is registered with ClinicalTrials.gov, number NCT00077610. FINDINGS: We excluded 133 of the 673 randomised patients from the per-protocol analysis because they had inadequate iron status or fewer than five haemoglobin measurements during the assessment period or needed red blood cell transfusions. The mean change from baseline haemoglobin for patients who had switched to intravenous methoxy polyethylene glycol-epoetin beta every 2 weeks (-0.71 g/L, 95% CI -2.20 to 0.77) or every 4 weeks (-0.25 g/L, -1.79 to 1.29) was non-inferior to the mean change for patients who continued treatment with epoetin (-0.75 g/L, -2.26 to 0.75) (p<0.0001 for both comparisons). Of the 666 patients who received at least one dose of study drug, the incidence of adverse events or serious adverse events did not differ between groups (p=0.30 and p=0.40, respectively). INTERPRETATION: This long-acting erythropoiesis-stimulating agent is as safe as conventional epoetin treatment, and can maintain anaemia management in haemodialysis patients when given intravenously at 4-week dosing intervals.

Expressed isolated integrin beta1 subunit cytodomain induces endothelial cell death secondary to detachment.

Expression of isolated beta integrin cytoplasmic domains in cultured endothelial cells was reported to induce cell detachment and death. To test whether cell death was the cause or the consequence of cell detachment, we expressed isolated integrin beta1 cytoplasmic and transmembrane domains (CH1) in cultured human umbilical vein endothelial cells (HUVEC), and monitored detachment, viability, caspase activation and signaling. CH1 expression induced dose-dependent cell detachment. At 24 h over 90% of CH1-expressing HUVEC were detached but largely viable (>85%). No evidence of pro-caspase-8,-3, and PARP cleavage or suppression of phosphorylation of ERK, PKB and Ikappa-B was observed. The caspase inhibitor z-VAD did not prevent cell detachment. At 48 h, however, CH1-expressing cells were over 50% dead. As a comparison trypsin-mediated detachment resulted in a time-dependent cell death, paralleled by caspase-3 activation and suppression of ERK, PKB and Ikappa-B phosphoyrylation at 24 h or later after detachment. HUVEC stimulation with agents that strengthen integrin-mediated adhesion (i.e. PMA, the Src inhibitor PP2 and COMP-Ang1) did not prevent CH1-induced detachment. Expression of CH1 in rat carotid artery endothelial cells in vivo caused endothelial cell detachment and increased nuclear DNA fragmentation among detached cells. A construct lacking the integrin cytoplasmic domain (CH2) had no effect on adhesion and cell viability in vitro and in vivo. These results demonstrate that isolated beta1 cytoplasmic domain expression induces caspase-independent detachment of viable endothelial cells and that death is secondary to detachment (i.e. anoikis). They also reveal an essential role for integrins in the adhesion and survival of quiescent endothelial cells in vivo.