Inhibition of neointimal hyperplasia in a sheep model of dialysis access failure with the bioabsorbable Vascular Wrap⁎⁎Vascular Wrap is a trademark of Angiotech Pharmaceuticals, Inc. paclitaxel-eluting mesh

ObjectiveThis study evaluated the effect of a bioabsorbable mesh containing paclitaxel on neointimal hyperplasia in a sheep model of dialysis access failure.MethodsForty neutered male sheep were randomized to one of five parallel groups: no mesh; or a 3-cm × 6-cm mesh with 0.0, 0.3, 0.7, or 1.2 μg/mm2 of paclitaxel for a total dose of 0.0, 0.6, 1.3, or 2.2 mg, respectively. Commercially available 6-mm internal diameter expanded polytetrafluoroethylene grafts were surgically placed between the left common carotid artery and the right external jugular vein. For those animals randomized to one of the mesh groups, the mesh was placed around the distal end of the graft and venous anastomosis. Patency was assessed at weekly intervals throughout the study. Animals were euthanized 8 weeks after implantation, and grafts and veins were harvested. After histologic processing, six cross sections were cut at the venous end of the graft and vessel. The primary and secondary efficacy outcome measures, respectively, were the area and capillary density of the neointima at the graft-vein anastomosis. Histologic analyses were also performed to investigate the effects of the paclitaxel-eluting mesh on the anastomotic site.ResultsGrafts occluded before the scheduled sacrifice in five animals, and they were excluded from the study and not replaced. Control animals developed significant neointimal hyperplasia at the cross section taken perpendicular to the graft at its most distal end: the neointimal area measured 10.5 ± 6.8 mm2 in the no mesh group and 6.4 ± 3.2 mm2 in the zero-dose mesh group (P = .28). In contrast, neointimal area was significantly reduced in the paclitaxel mesh groups: 0.9 ± 1.4 mm2 in the 0.3 μg/mm2 group (P = .008 vs zero-dose mesh), 1.3 ± 1.5 mm2 in the 0.7 μg/mm2 group (P = .004 vs zero-dose mesh), and 1.2 ± 1.4 mm2 in the 1.2 μg/mm2 group (P = .008 vs zero-dose mesh). Capillary density in the neointima at the graft-vein anastomosis decreased with paclitaxel and was significantly reduced in the paclitaxel mesh groups with 0.3 and 1.2 μg/mm2 compared with the zero-dose mesh control (3.6 ± 2.9 vs 8.9 ± 5.6 per mm2 [P = .022] and 1.1 ± 1.7 vs 8.9 ± 5.6 per mm2 [P = .001] respectively). The paclitaxel mesh had no significant effect on healing of the anastomosis or on the thickness of the adjacent vein.ConclusionsIn this model, the paclitaxel-eluting mesh significantly reduced neointimal hyperplasia and neointimal capillary density without apparent toxicity to the adjacent vein.Clinical RelevanceAlthough synthetic grafts (most commonly expanded polytetrafluoroethylene) are currently used in approximately 40% of hemodialysis patients who require a permanent vascular access, primary patency rates remain poor. Most graft failures are caused by venous neointimal hyperplasia, and there are no proven pharmacologic interventions that effectively prevent it. This study provides evidence of the safety and efficacy of a bioabsorbable paclitaxel-eluting mesh for inhibition of neointimal hyperplasia in a sheep model of dialysis access graft failure

Anti-infective external coating of central venous catheters: a randomized, noninferiority trial comparing 5-fluorouracil with chlorhexidine/silver sulfadiazine in preventing catheter colonization

OBJECTIVE: The antimetabolite drug, 5-fluorouracil, inhibits microbial growth. Coating of central venous catheters with 5-fluorouracil may reduce the risk of catheter infection. Our objective was to compare the safety and efficacy of central venous catheters externally coated with 5-fluorouracil with those coated with chlorhexidine and silver sulfadiazine. DESIGN: Prospective, single-blind, randomized, active-controlled, multicentered, noninferiority trial. SETTING: Twenty-five US medical center intensive care units. PATIENTS: A total of 960 adult patients requiring central venous catheterization for up to 28 days. INTERVENTIONS: Patients were randomized to receive a central venous catheter externally coated with either 5-fluorouracil (n = 480) or chlorhexidine and silver sulfadiazine (n = 480). MEASUREMENTS AND MAIN RESULTS: The primary antimicrobial outcome was a dichotomous measure (/= 15 colony-forming units) for catheter colonization determined by the roll plate method. Secondary antimicrobial outcomes included local site infection and catheter-related bloodstream infection. Central venous catheters coated with 5-fluorouracil were noninferior to chlorhexidine and silver sulfadiazine coated central venous catheters with respect to the incidence of catheter colonization (2.9% vs. 5.3%, respectively). Local site infection occurred in 1.4% of the 5-fluorouracil group and 0.9% of the chlorhexidine and silver sulfadiazine group. No episode of catheter-related bloodstream infection occurred in the 5-fluorouracil group, whereas two episodes were noted in the chlorhexidine and silver sulfadiazine group. Only Gram-positive organisms were cultured from 5-fluorouracil catheters, whereas Gram-positive bacteria, Gram-negative bacteria, and Candida were cultured from the chlorhexidine and silver sulfadiazine central venous catheters. Adverse events were comparable between the two central venous catheter coatings. CONCLUSIONS: Our results suggest that central venous catheters externally coated with 5-fluorouracil are a safe and effective alternative to catheters externally coated with chlorhexidine and silver sulfadiazine when used in critically ill patients

The Second of Two One-Year, Multicenter, Open-Label, Repeat-Dose, Phase II Safety Studies of PrabotulinumtoxinA for the Treatment of Moderate to Severe Glabellar Lines in Adult Patients

Abstract Background PrabotulinumtoxinA is a 900-kDa botulinum toxin type A produced by Clostridium botulinum. Objectives The authors sought to investigate the safety of prabotulinumtoxinA for treatment of glabellar lines. Methods This was a multicenter, open-label, repeat-dose, 1-year phase II safety study. Adults with moderate to severe glabellar lines at maximum frown, as independently assessed by both investigator and patient on the validated 4-point photonumeric Glabellar Line Scale (0 = no lines, 1 = mild, 2 = moderate, 3 = severe), were enrolled. On day 0, patients received an initial treatment (IT) of 20 U prabotulinumtoxinA (4 U/0.1 mL final vacuum-dried formulation injected into 5 glabellar sites). On and after day 90, patients received a repeat treatment (RT) if their Glabellar Line Scale score was ≥2 at maximum frown by investigator assessment. Safety outcomes were evaluated throughout the study. Results The 570 study patients received a median total dose of 60 U, that is, 3 treatments. Sixty-one patients (10.7%) experienced adverse events (AEs) assessed as possibly study drug related; 6.5% experienced study drug–related AEs after the IT. With each RT, progressively lower percentages of patients experienced study drug–related AEs. Eight patients (1.4%) experienced study drug–related AEs of special interest: 5 experienced eyelid ptosis (0.9%), 3 eyebrow ptosis (0.5%), 1 blepharospasm (0.2%), and 1 blurred vision (0.2%). Seven patients (1.2%) experienced serious AEs, but none were study drug related. A total of 4060 serum samples were tested for antibotulinum toxin antibodies; no seroconversion was observed. Conclusions The safety of RTs of 20 U of prabotulinumtoxinA for moderate to severe glabellar lines was confirmed in this second phase II study based on a broad range of outcomes