title: In vivo prophylactic activity of QR-435 against H3N2 influenza virus infection.
abstract: BACKGROUND
  Prophylaxis against influenza infection can take several forms, none of which is totally effective at preventing the spread of the disease. QR-435, an all-natural compound of green-tea extract and other agents, has been developed to protect against a range of viral infections, including the influenza subtype H3N2.
  
  
  METHODS
  Several different QR-435 formulations were tested against the two influenza A H3N2 viruses (A/Sydney/5/97 and A/Panama/2007/99) in the ferret model. Most experiments included negative (phosphate-buffered saline) and positive (oseltamivir 5 mg/kg, twice daily) controls. QR-435 and the control were administered 5 minutes after intranasal delivery of the virus as prophylaxis against infection resulting from exposure to infected but untreated ferrets and for prevention of transmission from infected and treated ferrets to untreated animals. Effects of QR-435 on seroconversion, virus shedding, and systemic sequelae of infection (weight loss, fever, reduced activity) were evaluated.
  
  
  RESULTS
  QR-435 prevented transmission and provided prophylaxis against influenza virus H3N2. Prophylaxis with QR-435 was significantly more than with oseltamivir in these experiments. Optimal in vivo efficacy of QR-435 requires a horseradish concentration of at least 50% of that in the original formulation, and the benefits of this preparation appear to be dose dependent.
  
  
  CONCLUSIONS
  QR-435 is effective for both prevention of H3N2 viral transmission and prophylaxis. These preclinical results warrant further evaluation of its prophylactic properties against avian influenza virus infection in humans.
authors: Retroscreen Virology, London, United Kingdom.
authors: John S
authors: JS
authors: Oxford
authors: Robert
authors: R
authors: Lambkin
authors: Mario
authors: M
authors: Guralnik
authors: Richard A
authors: RA
authors: Rosenbloom
authors: Michael P
authors: MP
authors: Petteruti
authors: Kelly
authors: K
authors: Digian
authors: Carolyn
authors: C
authors: LeFante
mesh_terms: D000281:Administration, Intranasal; D000284:Administration, Oral; D000818:Animals; D000998:Antiviral Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D031215:Armoracia / Q000737:chemistry; D004195:Disease Models, Animal; D005289:Ferrets; D005334:Fever / Q000188:drug therapy / Q000209:etiology; D017053:Infection Control / Q000379:methods; D053122:Influenza A Virus, H3N2 Subtype / Q000187:drug effects*; D009043:Motor Activity / Q000187:drug effects; D009976:Orthomyxoviridae Infections / Q000517:prevention & control* / Q000635:transmission; D053139:Oseltamivir / Q000627:therapeutic use; D010936:Plant Extracts / Q000008:administration & dosage / Q000627:therapeutic use*; D013662:Tea / Q000737:chemistry; D017201:Virus Shedding / Q000187:drug effects; D015431:Weight Loss / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; D010936:Plant Extracts; D013662:Tea; D053139:Oseltamivir