Talizumab (TNX-901) is a humanized monoclonal antibody being developed by Tanox in Houston, Texas. It was designed to target immunoglobulin E (or IgE) and IgE-expressing B lymphocytes specifically, without binding to IgE already bound by the IgE receptors on mast cells and basophils. Talizumab is being tested in clinical trials at National Jewish Medical and Research Center and other medical centers and allergy clinics across the U. S. Talizumab has been shown to be able to prevent allergic reactions to accidental exposure to peanuts, which is contained in many kinds of foods.
[edit] History
The U.S. Food and Drug Administration (FDA) has "fast-tracked" the drug. A drug is given fast-track status if it meets a medical need not currently being met by any medication. Talizumab was developed by a Houston-based company called Tanox. There was a legal dispute whether Tanox had the right to independently develop talizumab under the tripartite partnership formed by Tanox, Novartis, and Genentech in 1996. Trials of talizumab for treating extreme peanut sensitivity, which affect children especially, were mired in legal battles.[1]
[edit] Mechanism
Talizumab is an anti-IgE antibody.[2] IgE antibody is the receptor responsible for allergic reactions and severe asthma attacks. An anti-IgE antibody binds IgE and prevents it from initiating an allergic reaction.
[edit] Research
In clinical trials, people who were very allergic to peanuts when they consumed an average of half a peanut were able to consume up to 9 peanuts before they started to have symptoms.[3] Therefore the drug wouldn't cure allergies, but it would prevent reactions from accidental exposure. Note that this study was not done on people allergic enough to die from peanut traces.
[edit] Similar drugs
Another anti-IgE antibody with identical antigen-binding characteristics is already on the market for allergic asthma, under the name Xolair (omalizumab). Omalizumab is an anti-IgE monoclonal antibody, which was placed in a development program under a tripartite partnership formed by Tanox, Novartis, and Genentech in 1996. The problem is that Xolair isn't approved for use in food allergies and talizumab can't be released because Xolair's manufacturer sued Tanox for patent infringement. One could obtain a prescription for Xolair without it being approved for use in allergies, but most health insurance will not cover it without FDA approval, meaning it could cost on the order of $1000 a month for a patient.
Recently, talizumab has been shelved by its creator Tanox in exchange for some funding compensation from Genentech and Novartis, and the three companies plan to focus on researching Xolair for use against peanut allergies instead of talizumab. Xolair entered Phase II trials for use against peanut allergies in July 2004.
[edit] References
[edit] External links
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