Wednesday, November 30, 2011

"The Trenton Patient"

In Tuesday's New York Times, biotech writer Andrew Pollack has an overview of the work in progress to reach a cure for HIV, a story that we covered in the October issue of Start-Up.

Our favorite part of the story is Pollack's quotes from the anonymous HIV-positive patient whose early-stage clinical results were highlighted in September by Sangamo BioSciences. Sangamo's treatment SB-728-T aims to replace an HIV-positive person's immune cells with versions that lack the CCR5 receptor, the virus's main avenue of infection, and render them resistant to HIV.

The patient, who participated in a Phase I trial of SB-728-T at the University of Pennsylvania, was a lively interview. Identified only as "the Trenton patient," he told Pollack that the Sangamo treatment has made him feel both "like Superman" and "like Oliver Twist," the Dickensian orphan who held out his empty bowl and asked for more, please.

He might get his wish. As we explained in Start-Up (excerpted below), the Trenton patient's results were remarkable enough to encourage two more clinical trials, including one in patients who carry the same genetic quirk: 
The Penn trial also included a three-month interruption of the patients' HAART regimens to see if the gene therapy had any effect on viral load. In one patient, viral load went down until the virus was undetectable and stayed that way until the end of the treatment interruption. That patient turned out to be heterozygous; one of his two CCR5 genes was already mutant, which means the treatment resulted in a higher amount of biallelic modification in the patient – in other words, mutations to both copies of CCR5 genes. It's what [Sangamo CEO Edward] Lanphier calls "an important clue" that biallelic modification could have a strong correlation to reduction of viral load, and it will be the basis for Sangamo's next two studies scheduled to start in the first half of next year, with their clinical phase not yet determined. One study will focus on heterozygous patients specifically to see if results from the Penn trial patient can be repeated; the second study will use engraftment enhancement techniques already in use for cancer treatments to boost biallelic modification and make SB-728-T potentially applicable to a much broader HIV-positive population, not just heterozygotes.
For more on the revival of hope in HIV treatment, as well as some hard questions about who will fund the important work, read our story and let us know what you think.

Image courtesy of flickr user Sully Pixel via a Creative Commons license. 

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