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Biotech / Medical : ZymoGenetics ZGEN -- Ignore unavailable to you. Want to Upgrade?

To: tuck who wrote (193)	9/11/2009 11:11:10 AM
From: Steve Lokness	Respond to of 210

Interesting reaction to ZGEN news yesterday (reminds me of reaction to ALTH news a few days ago); UPDATE 1-ZymoGenetics' arthritis drug hits roadblock Thu Sep 10, * Says drug fails to meet disease-control activity level * Says further exploratory analyses underway Sept 10 (Reuters) - ZymoGenetics Inc (ZGEN.O) said preliminary results from a mid-stage trial of its experimental rheumatoid arthritis drug did not support a direct move to late-stage trials. The company said the drug atacicept failed to meet the pre-specified level of disease-control activity. ZymoGenetics's licensee Merck Serono, a unit of German drugmaker Merck KGaA (MRCG.DE), was developing atacicept as a treatment for systemic lupus erythematosus, multiple sclerosis and rheumatoid arthritis. ZymoGenetics said further exploratory analyses was on and Merck Serono has not made any decision regarding rheumatoid arthritis as a potential indication for atacicept. The company said trials for lupus and multiple sclerosis indications are currently ongoing. Shares of ZymoGenetics closed down 5 cents at $6.47 Thursday on Nasdaq. (Reporting by Anand Basu

To: tuck who wrote (193)	11/21/2009 2:09:28 PM
From: tuck	Read Replies (1) \| Respond to of 210

[Topical recombinant thrombin at a concentration of 1000 IU/mL reliably shortens in vivo TTH and delivers durable hemostasis in the presence of heparin anticoagulation and clopidogrel platelet inhibition in a rabbit model of vascular bleeding.] >>Ann Surg Innov Res. 2009 Nov 19;3(1):14. [Epub ahead of print] Topical recombinant thrombin at a concentration of 1000 IU/mL reliably shortens in vivo TTH and delivers durable hemostasis in the presence of heparin anticoagulation and clopidogrel platelet inhibition in a rabbit model of vascular bleeding. Hughes SD, Bishop PD, Garcia R, Zhang T, Alexander WA. ABSTRACT: BACKGROUND: This study was designed to evaluate the effect of recombinant human thrombin (rThrombin) concentration on time to hemostasis (TTH), clot durability, and clot strength in settings that replicate the heparinization and platelet inhibition often found in surgical populations. METHODS: A modified, anticoagulated rabbit arteriovenous shunt preparation was selected to model vascular anastomotic bleeding. Rabbits were treated with heparin or heparin + clopidogrel and TTH was measured after applying a range of topical rThrombin concentrations or placebo, in combination with absorbable gelatin sponge, USP. Treatments (placebo, rThrombin) were randomly assigned and the investigator was blinded to treatment. TTH was evaluated with the Kaplan-Meier method. After hemostasis was achieved, clot burst assessment was performed for heparin + clopidogrel treated animals. Clot viscoelastic strength and kinetics were measured in ex-vivo samples using thromboelastography (TEG) methods. RESULTS: TTH decreased with increasing concentrations of rThrombin in heparin-treated animals and was shorter after treatment with 1000 IU/mL rThrombin (73 seconds) than with 125 IU/mL rThrombin (78 seconds; p =0.007). TTH also decreased with increasing concentrations of rThrombin in heparin + clopidogrel treated animals; again it was significantly shorter after treatment with 1000 IU/mL rThrombin (71 seconds) than with 125 IU/mL rThrombin (177 seconds; p <0.001). Variability in TTH was significantly smaller after treatment with 1000 IU/mL rThrombin than after 125 IU/mL rThrombin, indicating greater reliability of clot formation (p <0.001 for heparin or heparin + clopidogrel treatments). Clot durability was examined in heparin + clopidogrel treated animals. Clots formed in the presence of 1000 IU/mL rThrombin were significantly less likely to rupture during clot burst assessment than those formed in the presence of 125 IU/mL rThrombin (0% versus 79%, p <0.001). In vitro clot strength and clot kinetics, as determined by TEG in heparin + clopidogrel samples, were positively associated with the amount of rThrombin activity added for clot initiation. CONCLUSIONS: In an animal model designed to replicate the anticoagulation regimens encountered in clinical settings, topical rThrombin at 1000 IU/mL more reliably controlled the pharmacological effects of heparin or heparin + clopidogrel on hemostasis than rThrombin at 125 IU/mL. Results from in vitro assessments confirmed a positive relationship between the amount of rThrombin activity and both the rate of clot formation and clot strength.<< The TTH improvement of 5 seconds likely does not mean much in a clinical setting, but the clot strength numbers are very clinically significant. I have not seen a similar study with bovine or plasma derived thrombin, though, and I would guess the numbers would be similar (I looked, and couldn't find one). So there's not likely to be much of a marketing edge here. Besides the gelatin sponge might well be contributing to clot strength, and one basically does not use thrombin without one . . . Cheers, Tuck