LONDON (AP) -- A new and unlicensed treatment for swine flu could be used in patients who have Tamiflu-resistant viruses, doctors say. In an article published Friday in the medical journal Lancet, British doctors describe how they used an intravenous form of the antiviral Relenza to treat a 22-year-old woman who had a severe case of swine flu. Relenza is usually inhaled via the nose, and is not licensed to be given intravenously.