Technology evaluation: T-cell activator, Xenova

TA-HPV (therapeutic antigen-human papilloma virus) is a vaccine being developed by Xenova (formerly Cantab) for the potential treatment of cervical cancer. The antigen is intended to activate HPV-specific cytotoxic T-cells to attack tumor cells containing the viral antigen. Over 70% of patients with cervical cancer have tumor cells containing papillomavirus DNA [173070]. TA-HPV has reached phase IIa trials in 60 patients with high-grade anogenital intraepithelial neoplasia, including VIN3 (grade 3 vulvar intraepithelial neoplasia), to evaluate clinical efficacy [381386], [427159], [429895]. In addition, a phase II 'prime-boost' study of TA-HPV in combination with TA-CIN has been initiated at three centers across the UK [427159]. In November 2000, Lehman Brothers predicted that the product would be launched in 2005, peak sales of £100 million in 2010, with a 25% probability of reaching the market [391876].