A rapidly gelling synthetic tissue sealant was developed from tetra-succinimidyl and tetra-thiol-derivatized polyethylene glycol (PEG). The two reagents were dissolved in aqueous buffers at 20% (w/v) solids and sprayed on the tissue site, with the use of a sprayer/mixer device. Good adhesion to collagen membranes, PTFE grafts, and carotid artery was observed in vitro. In a burst test on collagen membranes with a 2-mm orifice defect, the gel sustained fluid pressures of 125 +/- 36 mm Hg (n = 18), fivefold greater than capillary blood pressure and one-half that observed in hypertension. On 0.4-mm-diameter puncture defects in PTFE grafts, pressures of 390-490 mm Hg were sustained, and on 0.6-0.9-mm puncture defects in carotid arteries, pressures of 490 to 840 mm Hg were sustained. In vitro data corresponded to results in vivo, where bleeding in rabbit arteries was stopped immediately in five out of six trials. A significant reduction in time to hemostasis and blood loss, compared to controls, was observed. Carotid artery and subcutaneous implant data in rabbits showed that the formula was compatible with biological tissue. Rapid gelling and effective sealing were dependent on the presence of active succinimidyl ester and thiol groups on PEG. HPLC and chemical substitution methods were useful in predicting whether batches of derivatized PEG would perform satisfactorily.

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BackgroundStudies have evaluated the concomitant use of hyaluronan (HA) with steroids, anti-inflammatory drugs and analgesic agents in an attempt to magnify the extent and duration of pain relief due to knee osteoarthritis. To date there has not been an intra-articular combination therapy available for relief of knee osteoarthritis symptoms – one that combines the fast acting onset of symptom relief provided by a corticosteroid with the long-lasting symptom relief provided by HA in a single injection. The objective of this study was to evaluate the safety and preliminary performance of two new HA formulations, Hydros (hyaluronan-based hydrogel suspended in hyaluronan solution) and Hydros-TA (HA plus 10 mg of triamcinolone acetonide [TA]) in subjects with knee osteoarthritis.MethodsWe conducted a Phase 2 prospective, multicenter, randomized, double-blind feasibility trial. Participants (n = 98; mean age 60 years) with knee osteoarthritis (Kellgren-Lawrence grade 2 or 3) were randomized to three treatment groups: Hydros, Hydros-TA, and Synvisc-One® (hylan G-F 20). Participants received one 6 ml intra-articular injection in the treatment knee and were evaluated at 2, 6, 13, and 26 weeks post-treatment. Safety was assessed from adverse events at all study visits. The primary efficacy outcome was the change from baseline on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) A (Pain) score for the treatment knee.ResultsAdverse events were similar across treatment groups with the most common being arthralgia, joint swelling, back pain, and joint stiffness. Arthralgia was reported 5 times with Synvisc-One, 4 with Hydros, and 1 with Hydros-TA. Each group demonstrated a reduction in the WOMAC A (Pain) score over 26 weeks: [least-square mean (standard error)] 30.5 (5.1) mm for Hydros; 34.4 (4.7) mm for Hydros-TA; 28.0 (5.4) mm for Synvisc-One and an observed improvement of 2.5 mm (p = 0.64) and 6.4 mm (p = 0.24) over Synvisc-One for Hydros and Hydros-TA, respectively.ConclusionsA single injection of Hydros or Hydros-TA was well-tolerated and relieved pain associated with knee osteoarthritis over 26 weeks. Data indicate that Hydros-TA had a more rapid pain relief compared to Hydros alone. A Phase 3 trial is underway to confirm these preliminary results.Trial registration numberNCT01134406.

CoSeal mark surgical sealant (CoSeal) was evaluated for inhibiting suture line bleeding using a canine iliac PTFE graft model. Both iliac arteries of 12 heparinized canines were grafted with PTFE. CoSeal was applied to the suture lines of one graft in each animal. The contra-lateral graft served as a control and bleeding was controlled with gauze and pressure (tamponade). The cross-clamps were removed 30 s following application of CoSeal. Times to hemostasis and volume of blood loss at each graft site were determined. Compared to tamponade control, CoSeal significantly reduced the time to hemostasis (average of 5 min vs. greater than 15 min, p< 0.05) and blood loss (19 g vs. 284 g, p < 0.05). Small amounts of CoSeal were visible grossly or histologically at day 7. Histology showed moderate to marked inflammation in CoSeal sites and moderate inflammation in control sites at day 7. At 30 and 60 days, no CoSeal was visible grossly or histologically. Histology showed moderate inflammation in both CoSeal treated sites and in control sites at day 30 and mild to moderate inflammation in both CoSeal and control sites at day 60. CoSeal significantly reduced the time to hemostasis and blood loss in comparison to tamponade.

Bleeding is a problem encountered by many surgeons, often complicated by the presence of coagulopathy or anticoagulant. The hemostatic effectiveness of CoStasis Surgical Hemostat (with bovine collagen, bovine thrombin, and autologous plasma) was evaluated and compared to a collagen sponge and to two investigational fibrin-sealant preparations under conditions of normal and impaired coagulation. A liver resection and controlled incisions in spleens and kidneys were made in sheep. Time to complete hemostasis and total blood loss were measured. Tissue response was evaluated at 7, 30, 60, and 75 days. CoStasis-treated sites demonstrated significantly shorter time to hemostasis (all surgical sites combined) compared with fibrin sealant (investigational fibrin sealant 1) (p= .005) or collagen sponge (p=0.013). In anticoagulated animals, CoStasis and fibrin sealant (investigational fibrin sealant 2) had comparable mean times to hemostasis, and CoStasis-treated sites exhibited lowered average blood loss compared to investigational fibrin-sealant-2 treated sites. CoStasis-treated sites demonstrated higher levels of tissue repair (lower inflammation, more extensive tissue repair, and less residual implant) compared to fibrin-sealant- or collagen-sponge-treated sites in Phases I and II. These findings demonstrate that CoStasis is a highly effective hemostatic agent for control of bleeding from parenchymal organs. Furthermore, under conditions of compromised coagulation, treatment with CoStasis demonstrates a reduction in average blood loss when compared to treatment with fibrin sealant.