January 5, 2011

January 5, 2011
New Fusion Inhibitor

Welcome to another day in my life. Today is Wednesday and we have made it to the middle of another work week. I hope you are having a safe and great week so far.

I read some exciting news about scResearchers report early stage success with a novel anti-HIV compound derived from a natural substance in the body that effectively blocks HIV, according to a paper published December 22 by Science Translational Medicine.

The paper is an encouraging follow up to a report published in 2007, in which the same research team headed by Frank Kirchhoff, PhD, of the University of Ulm in Ulm, Germany, highlighted the discovery of fragments of a natural HIV blocking substance dubbed virus inhibitory peptide (VIRIP) and suggested a possible path to developing a new class of drugs to fight the infection.

According to the team’s report in the April 20, 2007, issue of Cell, VIRIP acts as a broad based HIV fusion/entry inhibitor. Specifically, VIRIP targets a conserved region in the HIV membrane protein known as gp41 fusion peptide. This peptide, which is normally buried in the viral envelope, becomes exposed during the process of viral entry and makes the first direct contact between the viral particle and host cell.

Moreover, researchers showed that a few amino acid changes in VIRIP enhanced its antiretroviral potency by two orders of magnitude.

VIRIP and its derivatives remained effective against drug resistant HIV strains, making them “highly promising for further clinical development,” according to the researchers.

“The findings reveal a new target for inhibiting HIV that remains fully active against viral strains that are resistant to other drugs,” said Kirchhoff in a 2007 statement. “That is a big advantage.”

In the more recent paper, reporting the results of a small clinical trial involving 18 previously untreated people living with HIV, the VIRIP derivative now called VIR 576 reduced viral loads by about 95 percent after 10 days of treatment using the highest dose studied. Using a large 5 gram dose of the drug, viral loads dropped, on average, by 1.23 log; lower doses of the drug were associated with average viral load reductions that were less than 0.5 log.

VIR 576 was found to be well tolerated. The most common side effects, all mild to moderate in intensity, were constipation, headache and fever. A few allergic reactions were documented, but only among those in the two lower-dose groups.

Elevated bilirubin levels were also detected in two patients.

Kirchhoff and his colleagues note that VIR 576 may not move forward into more advanced clinical trials because the current formulation is expensive and must be administered intravenously. Kirchhoff’s team, working in collaboration with scientists at VIRO Pharmaceuticals in Hannover, Germany, is currently developing a small molecule that can be delivered orally and affordably.

So stay tuned for developing news. Now we just have to find a way for Americans to be able to continue to get their life saving HIV medications.

Until we meet again; here's wishing you health, hope, happiness and just enough.

big bear hug,

Daddy Dab