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Biotech / Medical : Cell Therapeutics (CTIC) -- Ignore unavailable to you. Want to Upgrade?

To: Icebrg who wrote (176)	1/8/2004 7:56:37 AM
From: Thai Chung	Respond to of 946

Press Release Source: Cell Therapeutics, Inc. Cell Therapeutics Honored with Keynote Address on XYOTAX(TM) at International Symposium on Polymer Therapeutics Thursday January 8, 7:01 am ET Polymer's Unique Mechanism of Action May Enhance Drug's Cancer Fighting Effects While Minimizing Toxicities SEATTLE, Jan. 8 /PRNewswire-FirstCall/ -- At the 6th International Symposium on Polymer Therapeutics in Cardiff, Wales, Cell Therapeutics, Inc. (Nasdaq: CTIC - News; CTI) was honored with a keynote presentation on XYOTAX, CTI's drug candidate that links paclitaxel, the active chemotherapy agent used in Taxol®, to a water soluble, biodegradable, polyglutamate polymer. In his keynote address Jack W. Singer, M.D. Vice President and Research Chair at CTI explained that XYOTAX was developed to provide a potentially more effective treatment with fewer toxicities. To date, more than 1200 patients have been treated with XYOTAX in clinical trials. ADVERTISEMENT "Based on data from preclinical studies it appears that XYOTAX patients have approximately 100 times less free paclitaxel in their blood stream than patients receiving an equivalent dose of marketed paclitaxel products," said Singer. "This unique profile may be responsible for the lack of hair loss and the markedly lower incidence of severe neutropenia observed in clinical studies with XYOTAX." Singer explained that data from nonclinical studies show that the biodegradable, polyglutamate polymer allows the chemotherapy to penetrate the tumor cell through a mechanism unique to this polymer delivering the cancer fighting agent directly to the heart of tumor. Once localized in the tumor cell, enzymes in the tumor (cathepsinB) play a key role in digesting the polymer, releasing higher levels of paclitaxel in the tumor cell than are achievable with equivalent doses of marketed paclitaxel products. In addition to the XYOTAX data, Singer also presented an overview of preclinical data on CT-2106, a polymer-linked camptothecin. He said this research shows early evidence of anti-tumor activity and predictable toxicity for CT-2106, which is expected to enter phase II trials this year. XYOTAX is in phase III development for non-small cell lung cancer and entering into phase III development for ovarian cancer. It is also being studied in combination with radiation in solid tumors

To: Icebrg who wrote (176)	1/14/2004 8:02:02 AM
From: Icebrg	Read Replies (1) \| Respond to of 946

The metabolism of inorganic arsenic oxides, gallium arsenide, and arsine: a toxicochemical review. Carter DE, Aposhian HV, Gandolfi AJ. Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ 85721-0207, USA. gandolfi@pharmacy.arizona.edu The aim of this review is to compare the metabolism, chemistry, and biological effects to determine if either of the industrial arsenicals (arsine and gallium arsenide) act like the environmental arsenic oxides (arsenite and arsenate). The metabolism of the arsenic oxides has been extensively investigated in the past 4 years and the differences between the arsenic metabolites in the oxidation states +III versus +V and with one or two methyl groups added have shown increased importance. The arsenic oxide metabolism has been compared with arsine (oxidation state -III) and arsenide (oxidation state between 0 to -III). The different metabolites appear to have different strengths of reaction for binding arsenic (III) to thiol groups, their oxidation-reduction reactions and their forming an arsenic-carbon bond. It is unclear if the differences in parameters such as the presence or absence of methyl metabolites, the rates of AsV reduction compared to the rates of AsIII oxidation, or the competition of phosphate and arsenate for cellular uptake are large enough to change biological effects. The arsine rate of decomposition, products of metabolism, target organ of toxic action, and protein binding appeared to support an oxidized arsenic metabolite. This arsine metabolite was very different from anything made by the arsenic oxides. The gallium arsenide had a lower solubility than any other arsenic compound and it had a disproportionate intensity of lung damage to suggest that the GaAs had a site of contact interaction and that oxidation reactions were important in its toxicity. The urinary metabolites after GaAs exposure were the same as excreted by arsenic oxides but the chemical compounds responsible for the toxic effects of GaAs are different from the arsenic oxides. The review concludes that there is insufficient evidence to equate the different arsenic compounds. There are several differences in the toxicity of the arsenic compounds that will require substantial research. ncbi.nlm.nih.gov