Erik,
Thanks. I understand that Xyotax is specific to Paclitaxel.
All the same, I believe that CTIC's promise is in its Polyglutamate Polymer delivery system and the ability to deliver a wide variety of cancer drugs selectively to the tumour.
Am I overestimating the potential value of this capability?
Ian
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Background: ctiseattle.com
Polyglutamate Drug Delivery Technology
We are developing a new way to deliver cancer drugs more selectively to tumor tissue to reduce the toxic side effects to normal organs and tissues and to improve the anti-tumor activity of existing chemotherapy agents.
Our technology links, or conjugates, cancer drugs to biodegradable polymers, such as polyglutamate. Two of our product candidates, XYOTAX™ and CT-2106, use a unique biodegradable protein polymer to deliver a taxane and a camptothecin, respectively, more selectively to tumor tissue.
Mechanism of Action
Because tumor blood vessels are more porous than those in normal tissue, polymers within a specific size range circulate in the bloodstream and get trapped in tumor tissue and accumulate preferentially within the tumor. In the tumor tissue, the polymer cancer drug is taken up by cells. The polymer bound cancer drugs are inactive while circulating in the bloodstream, which may also lower toxicity compared to the active cancer drug substance alone.
Once within a cell, naturally occurring enzymes digest the polymer releasing the chemotherapy drug. Preclinical animal studies and human clinical data to date indicate that our polyglutamate technology may allow more drug to reach the tumor, provide increased efficacy using the same amount of chemotherapy drug and less toxicity at the same or higher equivalent doses of drug, as compared to unlinked cancer drugs.
• PG technology and selective delivery of tumor-killing drug
Quicktime video (2mb) ctiseattle.com
Based on in vitro and in vivo research in preclinical models
Possible Benefits of Polyglutamate Technology
Based on preclinical animal studies and phase I and preliminary phase II clinical trial data, we believe that our polymer-cancer drug conjugates may be able to achieve a number of benefits over existing chemotherapy drugs, including:
* Eliminates the need for toxic solubilizing agents such as Cremophor/ethanol
* Eliminates the need for routine premedication
* Allows more drug to reach the tumor
* Less active drug to reach normal tissues resulting in decreased toxicity
* Increases efficacy using the same amount of active drug
* Lessens toxicity at the same or higher doses of active drug
* Has potential to overcome resistance to the underlying chemotherapy drug
History & Strategy of the Polyglutamate Technology
We licensed the worldwide exclusive rights to polyglutamate and related polymers and their applications from PG-TXL Company in 1998. The technology was originally developed at the M.D. Anderson Cancer Center. The initial patent, which issued in November 1999, covers polyglutamate and related polymers coupled with commonly used cancer drugs such as paclitaxel, docetaxel, etoposide, teniposide, or camptothecins. The patented technology covers formulations of polyglutamate-conjugated paclitaxel that also include the use of human serum albumin and conjugation to epothilones.
Our strategy is to use this novel polymer technology to build a portfolio of potentially safer and more effective versions of well-known anti-cancer agents. We believe that our polymer drug development program may lower the risks inherent in developing new drugs because we are linking polymers to well defined and widely used chemotherapy drugs. We are initially focusing our development efforts on applying polyglutamate to two of the fastest growing classes of anticancer drugs, taxanes and camptothecins.
See our Clinical Pipeline section for more information on the applications of this technology - XYOTAX™ and CT-2106. |
