Tuesday, May 1, 2007

Autoimmune Vaccine-Cytos Biotechnology

Cytos Biotechnology, a Swiss, company, is developing a number of vaccines that if successful could revolutionized the treatment of autoimmune disease, tobacco addiction, excess weight problems (metabolic disorder-type 2 diabetes), allergy, asthma, and eczema.

The autoimmune vaccine is meant to cause our bodies to produce our own antibodies to TNF-alpha. Instead of paying $1000-3000US a month to buy mouse and hamster antibodies o TNF alpha, we would make our own!

TNF-alpha is the chief immune system messenger causing inflammation. It is the main target of the biologics for various autoimmune arthritis diseases. The vaccine, if it works, will be useful for any autoimmune patient who takes Remicade, Humira, or Enbrel.

Cytos picked plaque psoriasis, probably because of the ease of visually assessing progress should the vaccine work. Pictures sell product. But just because Cytos started with plaque psoriasis does not mean the vaccine wouldn't help many (most) other autoimmune conditions.

Remicade is a mouse antibody that attacks TNF-alpha when injected into us. Humira is a fully human antibody that also attacks TNF-alpha. Enbrel is a Chinese hamster ovary fusion protein whose target is again, TNF-alpha.

The problem with each of these is that over time our body's own immune system starts to make antibodies against these medicines destroying them before they can destroy the TNF-alpha. The longer we take these biologics the less likely they are to work. Worse yet, for the ten percent of us who get hypersensitivity reactions, the longer we inject any foreign antibodies or proteins, the more likely we are to have a life threatening reaction.

The Cytos vaccine gets around this problem by stimulating our own immune systems to destroy TNF-alpha with our own antibodies. Good idea.

Now the bad news, clinical trial results for phase II use of this anti-TNF-alpha vaccine were supposed to be announced last fall. A quick Google search finds no mention of these results being announced. Why? Did it take longer to register clinical trial subjects than anticipated, thus delaying the start of the trials? Did the vaccine fail to work? or Did it work too well?

If it worked too well volunteers may have had too high a rate of infections and cancers. TNF-alpha is crucial for the prevention of both. So while reducing the amount of TNF-alpha is a good idea, getting rid of all of it is not so good. Who knows what caused the delay? I have emailed Cytos to ask them these questions. We will have to wait for Cytos to reply. In the meantime, read more below.

Here is a summary of how the vaccine is supposed to work. It is from the Cytos website. Here is the URL:
Then skip down to the following:
"View information about the vaccine CYT007-TNFQb to treat psoriasis."
Click on this button: TNFQb Facts English or read part of the article below.

Proposed Mode of Action
CYT007-TNFQb is a therapeutic vaccine designed to instruct the patient's immune system to produce a specific anti-TNF-α antibody response that is able to neutralize the action of TNF-α.

This should prevent the binding of TNF-α to its receptors TNF receptor I or TNF receptor II, which are expressed by many different cell types, and reduce the subsequent inflammatory response.

In contrast to TNF-α inhibitors based on recombinant proteins and monoclonal antibodies, which have to be administered frequently and in high doses, CYT007-TNFQb represents an active immunization that is expected to have a long-lasting effect and thus allow for more convenient dosing schedules.

TNF-α, a cytokine predominately produced by macrophages, is a potent inducer of inflammatory responses and a key regulator of innate and adaptive immunity.

For its Immunodrug™ candidate, Cytos Biotechnology has selected an appropriate peptide of TNF-α that is directionally placed onto the highly repetitive carrier particle Qb (a virus-like particle) using the Immunodrug™ technology. The normally non-immunogenic peptide is now presented to the immune system in a highly organized array and has the ability to induce strong anti-TNF-α antibody responses.

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