June 6, 2008

A New Improved HIV Tropism Test

A new version of the Trofile HIV tropism test is far more effective than the original assay at determining whether a person will likely respond to the entry inhibitor Selzentry (maraviroc), according to a press release issued by Monogram Biosciences. The test is now available to anyone who needs tropism testing.

Tropism testing is necessary if Selzentry is to be included in an antiretroviral regimen and is used to determine which coreceptor on CD4 cells a person’s HIV is using: CCR5, CXCR4 or both (dual/mixed). Selzentry is effective against CCR5-using HIV only, not dual/mixed or CXCR4-using virus.

The original Trofile test, which became available with the approval of Selzentry last August, was only sensitive enough to accurately detect dual/mixed virus if it made up more than 10 percent of the HIV population in a person’s blood sample. This meant that a significant number of people were at risk of receiving a test result indicating that Selzentry should work well, only to quickly experience treatment failure. The new enhanced Trofile test is 100 percent sensitive at detecting dual/mixed virus making up as little as 0.3 percent of the HIV population in a blood sample.

A representative for Monogram stated that there will be no increase in price over the older Trofile test.

Search: Trofile, Monogram, Biosciences, tropism, Selzentry, maraviroc

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Previous Comments:

Brian Greul, Houston, 2008-06-10 14:17:31
Schering Plough is currently doing Phase III trials for vicriviroc (their entry inhibitor) and they will do the trofile assay as part of the screening. They have trials for both treatment naive and treatment experienced people.

Jauri, SF, 2008-06-09 12:29:27
I was really looking forward to get this test and try Selzentry but unfortunately i cannot afford the $2K price for it , the good news is that the treatments available are really good as well , I'm newly infected and drug naive, but for people with resistance issues this can be a miracle drug , i really hope it works for the best as a new class , we are very lucky to have this advanced new approaches , good luck to all .