A massive, data-crunching computer search program that matches fragments of potential drug molecules to the known shapes of viral surface proteins has identified several FDA-approved drugs that could be the basis for new medicines -- if emerging viruses such as the H5N1(avian flu ) or H1N1/09 ( swine flu ) develop resistance to current antiviral therapies -- according to a presentation at the American Society for Cell Biology (ASCB) 49th Annual Meeting, Dec. 5-9, 2009 in San Diego. The compounds were identified through a "rational drug design" project in the laboratory of Andrew McCammon, Ph.D., HHMI investigator at the University of California at San Diego. The McCammon lab honed the search algorithms that helped identify the second generation of anti-HIV drugs. Like fitting a key to a lock, computer search algorithms take the known shapes of drugs and match them, one after another, to the known shapes of disease-related proteins.
Medicago Inc. (TSX-V: MDG) a biotechnology company focused on developing highly effective and affordable vaccines based on proprietary manufacturing technologies and Virus-Like Particles (VLPs), reported positive interim results from a Phase I human clinical trial with its H5N1 Avian Influenza vaccine candidate ("H5N1 vaccine"). The vaccine was found to be safe, well tolerated and also induced a solid immune response. "We are very pleased with the results from this study. This trial was the first ever clinical evaluation of a plant-based Influenza VLP vaccine and shows that Medicago's vaccine is safe in humans, " said Andy Sheldon, President and CEO of Medicago. "We believe our novel vaccine candidate, coupled with our rapid response and low cost manufacturing system offers a preferred option to increase the speed of a public health response in the event of a pandemic outbreak.
The specter of a drug-resistant form of the deadly H5N1 avian influenza is a nightmare to keep public-health officials awake at night. Now, however, a study published this week (Dec. 21) in the Proceedings of the National Academy of Sciences (PNAS) suggests that a new compound, one on the threshold of final testing in humans, may be more potent and safer for treating " bird flu " than the antiviral drug best known by the trade name Tamiflu. Known as T-705, the compound even works several days after infection, according to Yoshihiro Kawaoka, a University of Wisconsin-Madison virologist and the senior author of the new PNAS study. "H5N1 virus is so pathogenic even Tamiflu doesn't protect all the infected animals, " explains Kawaoka, a professor of pathobiological sciences at the UW-Madison School of Veterinary Medicine and a world authority on influenza.
A farm with a case of Avian influenza, also known as bird flu, is being investigated by the US Department of Agriculture (USDA). Authorities say the poultry in the farm has been quarantined after initial laboratory results were returned. The Department of Agriculture describes the Avian influenza as the low pathogenic virus strain H7N3. Authorities add that the virus typically affects birds and extremely rarely affects humans. The National Veterinary Services Laboratory, in Ames, Iowa is currently carrying out tests to determine exactly what type of disease it is. All poultry within a six mile radius of the affected farm are being tested for Avian influenza. Authorities say the Missouri Department of Agriculture, the Missouri Department of Health, as well as Senior Services are liaising closely with the USDA.
The persistence and recurrence of H5N1 avian influenza in endemic regions can largely be blamed on movement and infection by migratory birds. Trade in poultry, poultry products and caged birds, and movement of wild birds also account for H5N1 prevalence in these areas. Several recent outbreaks of avian influenza have suggested strong evidence of migratory birds playing a role in transmitting the virus over long distances. In a paper published last week in the SIAM Journal on Applied Mathematics, authors Lydia Bourouiba, Stephen A. Gourley, Rongsong Liu, and Jianhong Wu analyze the interaction between non-migratory poultry and migratory birds in order to investigate the role of the latter in the spread of H5N1. Although avian influenza rarely infects humans, occasional cases of human infection have been observed since the late nineties.