A consortium of researchers has detailed the activity of a novel drug compound that kills multiple HIV strains via a unique mechanism of action. The discovery brings with it hope in using this compound in both topical and systemic applications for HIV therapy.
The compound is just one belonging to the Ceragenin (CSA) family. They are synthetically produced small molecule chemical compounds comprised of a sterol backbone with amino acids and other chemical groups attached to them.
These compounds have a net positive charge that is electrostatically attracted to the negatively charged cell membranes of certain viruses, fungi and bacteria. CSAs have a high binding affinity for such membranes (including Lipid A) and are able to rapidly disrupt the target membranes leading to rapid cell death.
While CSAs have a mechanism of action that is also seen in antimicrobial peptides, which form part of the body's innate immune system, they avoid many of the difficulties associated with their use as medicines.
Scientists from the Vanderbilt and Brigham Young Universities as well as Ceragenix Pharmaceuticals, demonstrated broad spectrum antibacterial activity with the CSAs with one candidate, CSA-54, potently inhibiting HIV infection of primary human CD4+ T cells, the virus's in vivo targets.
Additionally, the compound was found not to be toxic to epithelial cells at concentrations significantly higher than those required to kill the virus.
"CSA-54 killed a wide range of HIV isolates, and completely blocked genetically engineered HIV that enters the cells independent of the cell surface receptor the virus normally uses," said Derya Unutmaz, associate professor of Microbiology and Immunology at the Vanderbilt University School of Medicine.
This finding indicates that CSA-54 most likely attacks the viral membrane and disrupts the virus from interacting with its target cells, similar to some of the known microbicidal peptides.
This is important, as a compound that targets the viral membrane is likely to be effective against all strains of the virus, regardless of mutations, as the viral membrane remains unchanged.
"We are encouraged, based on these early in vitro studies, that CSAs may provide a completely unique family of anti-infectives, potentially active against a wide range of viral, fungal, and bacterial targets, including those resistant to current therapies," said Steven Porter, CEO of Ceragenix
"Given the potent activity of CSA-54 against all strains of HIV tested, we plan on exploring the use of this compound in both topical and systemic applications for HIV therapy."
Ceragenix have been boosted by the news that the potential uses of Ceragenins are much broader than their application in AIDS drugs, having also shown promise in fighting microbial and bacteria infections.
Indeed, late last year, the company demonstrated the antibacterial properties of CSA-13 against vancomycin resistant staph aureus ("VRSA"), vancomycin intermediate resistant staph aureus strains ("VISA"), vancomycin resistant erterococci ("VRE"), community associated methicillin-resistant staph aureus ("CA-MRSA") and hospital acquired MRSA, as well as key gram negative pathogens such as pseudomonas aueroginosa and E. Coli, and bioterrorism surrogate strains for anthrax, listeria and plague.