Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

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

To: LLCF who wrote (1213)	6/22/1999 2:04:00 AM
From: Jongmans	Respond to of 1352

Article in Washington Post, dd 06/22/99: Gene Therapy Aims to Cure Hemophilia. washingtonpost.com Martin

To: LLCF who wrote (1213)	6/26/1999 9:47:00 PM
From: Walkingshadow	Respond to of 1352

I recently ran across two articles which appeared in the journal Nature Medicine (Jan. 1999), along with an accompanying editorial. In these two studies, investigators (some from Avigen, Inc) attempted to deliver the factor IX gene to dogs suffering from a naturally occuring canine hemophilia which is very similar to most of the human types. Both studies utilized adeno-associated virus vector to deliver the genes, one via intramuscular injection, and the other via injection into the portal vein (which passes into the liver, the site of factor IX synthesis). Both groups achieved partial correction of the hemophilia in the dogs. However, it should be noted that it does not take much of an effect to achieve partial correction: the blood levels of factor IX were only about 1% of normal. Clearly, this disease was chosen for study in part because a minimal response is sufficient to effectively treat the disease. Also, the effects on serum levels of factor IX were persistent (8 and 16 months). Of particular note was the vector chosen. The adeno-associated virus, which was "gutless" (i.e., viral genes are not present), elicited no immune response against either the vector or the transgene product. This vector would appear to show promise in human gene therapy trials, but the results would first have to be replicated in humans. A problem with this is that currently there is no method to produce the vector in quantities sufficient for human therapeutic use. So, it would appear that there is some good news here, but problems remain to be worked out. Meanwhile, Chiron's attempts at gene therapy in human hemophiliacs proceeds: washingtonpost.com hemophilia22.html Does anyone know whether these human studies utilized the adeno-associated virus vector? Does anyone have an update on preliminary results?? Thanks, Walkingshadow