Northwest Biotherapeutics is developing a prostate cancer vaccine based on its proprietary dendritic-cell based vaccine technology (DCVax™).1The vaccine (DCVax™-Prostate, CaPVax, DC1/HRPC) consists of prostate-specific membrane antigen (PSMA)-pulsed autologous dendritic cells and is in phase III development in the USA.On 15 February 2000, Northwest Biotherapeutics announced that a phase I/Il trial of the vaccine had begun at the MD Anderson Cancer Center in Houston and the University of California at Los Angeles. The study is enrolling 60 patients (30 at each site) with hormone-refractory, metastatic prostate cancer who are receiving four intradermal vaccinations at 4-week intervals of autologous dendritic cells pulsed with full-length PSMA, granulocyte-macrophage colony-stimulating factor, interleukin-4 and Bacille-Calmette-Guerin. In March 2002, Northwest Biotherapeutics announced that it had recently initiated a 495 patient phase III clinical trial in patients with late-stage prostate cancer. The trial will be conducted at 20 to 25 sites in the USA.Northwest Biotherapeutics has sublicensed the use of PSMA forex vivoimmunotherapy of prostate cancer from Cytogen Corporation. Cytogen licensed worldwide rights to use of PSMA for immunotherapy from the Memorial Sloan-Kettering Cancer Center in New York, USA, where the antigen was discovered. Cytogen has retained the rights for use of PSMA for all other indications, includingin vivoimmunotherapy for prostate cancer. In exchange for the sublicensing agreement, Northwest Biotherapeutics will make milestone and royalty payments to Cytogen. Previously, in January 1997, Cytogen had licensed PSMA to Prostagen, which initiated a collaboration with Northwest Biotherapeutics for development of the vaccine. However, in June 1999, Cytogen acquired Prostagen, thus regaining rights to PSMA. As part of this deal, Cytogen received a minority ownership in Northwest Biotherapeutics.