VIENNA, Feb. 27 (Xinhua) -- Austrian scientists have developed a vaccine against human papilloma virus (HPV) that could provide broader protection against infections.
The vaccine currently most effective protects against about 70 percent of cervical cancers and 90 percent of genital warts caused by HPV. Researchers at the Vienna General Hospital's (AKH) Dermatological University Clinic believe they have a vaccine that could cover the rest.
"We can now show that, in mice and rabbits, robust protection against 20 HPV variants can be had for up to two years after vaccination," research head Reinhard Kirnbauer from the AKH Division of Immunology told Austria Presse Agentur (APA).
Kirnbauer has previously worked on important foundations for currently licensed HPV vaccines while based in the U.S. They are based on generating empty virus-like particles that are injected together with an immunostimulatory adjuvant in the form of the vaccine.
The researchers noticed that capsid protein L2 of the HPV's vaccine component caused a weaker immune response than L1 protein, but had a much wider effect. They then constructed further virus-like particles of L1 with a portion of L2 inserted, and added an adjuvant to enhance the immunogenicity of the vaccine.
The tests on animals have thus far been extremely effective, protecting against viruses that cause cervical and other HPV-caused cancers, and also seem to immunize against HPV strains that cause genital warts and simple skin warts as well as squamous-cell carcinoma.
The team is now moving on to phase 1 studies of the vaccine, where it will test the vaccine on human subjects. Another vaccine that protects against nine HPV variants is currently in advanced stages of completion by a pharmaceutical company, though the vaccine from the Viennese team should have an even broader effect.