Viventia Biotech initiates patient treatment for Vicinium Phase II bladder cancer trial

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Viventia Biotech Inc. initiates patient treatment in its open-label Phase II clinical trial for Vicinium(TM), administered using intravesical instillation for the treatment of locally persistent non-invasive bladder cancer. The trial, which will initially enroll patients in Canada before expanding into the U.S., is expected to be fully enrolled by Q4 2007.

Viventia's lead product, Proxinium(TM), is being developed to treat late stage, locally advanced head and neck cancer and is currently enrolling patients in its TARGET trial, a pivotal Phase III global clinical trial that is also expected to complete accrual by the end of 2007.

Vicinium(TM) and Proxinium(TM) are Armed Antibodies(TM) that target the cancer antigen EpCAM.

Initially, patients will be administered Vicinium(TM) weekly using intravesical instillation over a period of six weeks. After this six week induction treatment phase, patients responsive to therapy may receive up to three additional maintenance cycles of Vicinium(TM) scheduled over a total treatment period of 51 weeks. The primary clinical endpoint will be overall response rate assessed using histology of biopsy samples and urinary cytology.

Vicinium(TM) has completed a dose escalation Phase I/II clinical trial in 64 patients with high risk, non-invasive bladder cancer. Dosed on a weekly basis for six weeks, Vicinium(TM) was very well tolerated at all dose levels, demonstrating a safety profile far more favorable than those of established therapies.

Moreover, significant tumor responses were also observed in this study: 42% of patients achieved a complete response, 13% had a partial response and 40% had stable disease, for an overall response rate of 95%. The early clinical benefit observed with Vicinium(TM) strongly supported further clinical development as a therapy for superficial transitional cell carcinoma of the bladder.