Pivotal phase III TARGET trial on track to deliver interim data in late-2007



TORONTO, Canada | Feb 14, 2007 | 
Viventia Biotech Inc., a privately held biopharmaceutical company advancing a portfolio of novel antibody products focused on cancer, today provided an update on the clinical development programs for its late-stage antibodies: Proxinum(TM), Vicinium(TM) and VB6-845.

Viventia’s lead drug, Proxinium(TM), is undergoing a global pivotal Phase II/III clinical trial (the ‘TARGET’ trial) and a U.S./Canadian Phase II trial, both in patients with advanced head and neck cancer. In December 2006, the independent Data Safety Monitoring Board (DSMB) reviewed Phase II data from the TARGET trial and unanimously recommended that it proceed to the Phase III portion. Interim efficacy data from the TARGET trial is anticipated in late 2007 and enrolment is expected to be complete in the first quarter of 2008.

"Our unique approach to creating cancer drugs has yielded a strong late-stage portfolio," said Dr. Nick Glover, President and CEO of Viventia Biotech, speaking at the BIO CEO & Investor Conference 2007 in New York. "Our ongoing pivotal trial for Proxinium(TM) is advancing as planned and the drug continues to demonstrate a good safety profile. We are optimistic about the prospects for this drug based on previous clinical trials for Proxinium(TM), which produced very encouraging efficacy results including a survival trend in patients with refractory head & neck cancer. Reinforcing our clinical pipeline, we are initiating both a Phase II trial for Vicinium(TM) and a Phase I trial for our exciting and novel anti-metastatic cancer drug, VB6-845, in the first quarter of 2007."

Commenting on Viventia’s commercialization strategy, Dr. Glover noted: "Viventia Biotech retains full global product rights to all of its drug candidates and technology platforms. In 2007 we intend to intensify our business development efforts with a view to identifying and selecting a partner capable of complementing our development expertise with their global sales, marketing and commercial capabilities."

Viventia Biotech Armed Antibodies(TM) are a new class of therapeutic anti-cancer products designed to be safer and more beneficial for cancer patients, based on an approach that leverages the principles of Power and Precision. The Power of these anti-cancer product candidates is derived from the potency of certain extremely active naturally occurring proteins, which are among the most lethal cancer killing agents known. This power is harnessed by engineering the natural proteins so that they retain all of their intrinsic potency, but in a form that is only activated when inside a cancer cell, yielding an exceptionally potent drug that is also far safer than typical chemotherapies. The Precision of Viventia’s product candidates comes from the cancer-targeting properties of monoclonal antibodies, carefully selected for their ability to specifically and preferentially bind to cancer cells. Viventia employs only the component of its engineered human or humanized monoclonal antibodies that is required to recognize and bind to its target on a cancer cell.

Proxinium(TM)

The TARGET pivotal trial is being conducted globally at more than 100 centers in more than 15 countries. The randomized trial will enroll approximately 300 patients with advanced head and neck cancer and compare Proxinium(TM) monotherapy against best supportive care. The primary endpoint is survival, with secondary endpoints of response rate, progression free survival, and quality of life. The single-arm Phase II North American study in the same indication will enroll approximately 20 patients and is being conducted concurrently. Proxinium(TM) has Orphan Drug status in both the U.S. and Europe and has been designated as a Fast Track product by the U.S. FDA.

Two clinical trials have been completed with Proxinium(TM) in patients with head and neck cancer. In 18 evaluable patients who received direct intratumoural injection of the drug on a weekly basis for 4 weeks as a monotherapy, 25% of patients who expressed the therapeutic target for Proxinium(TM) had a complete response and 88% had tumor growth control (objective response or stabilization of disease). In a 24 patient Phase I dose-escalation trial, Proxinium(TM) injected intratumorally on a monthly schedule yielded an objective response rate of 43% and a tumor growth control rate of 71% from those patients that expressed the EpCAM antigen. The median survival rate for EpCAM positive patients who showed a response to Proxinium(TM) reported from this study was 301 days, compared to a median survival of 125 days for those patients that were EpCAM negative, similar to the expected median survival of approximately 120-150 days.

Globally, head and neck cancer is the sixth most common form of cancer and recurs in 60-70% of patients. To support the TARGET trial, Viventia has launched the website www.proxinium.com, serving as a resource for patients and clinicians.

Vicinium(TM)

Viventia’s second late-stage clinical product is Vicinium(TM), which is entering into a Phase II clinical study for the treatment of locally recurrent non-invasive bladder cancer that will be initiated in the first quarter of 2007. The trial will enroll approximately 30 patients, initially in Canada and then expanding into the U.S.

Vicinium(TM) has completed a Phase I/II clinical trial in 64 patients with high risk, non-invasive bladder cancer. Dosed on a weekly basis for 6 weeks, Vicinium(TM) was very well tolerated at all dose levels. Moreover, significant anti-tumor responses were also observed in this study: 42% of patients demonstrated 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 supports its development as a promising therapy for superficial transitional cell carcinoma of the bladder.

VB6-845

VB6-845 is a humanized antibody fragment targeting EpCAM fused with the Company’s proprietary deimmunized form of the cytotoxin Bouganin and is designed for systemic use against metastatic cancer. Viventia is initiating a Phase I dose escalation trial in solid tumors in the first quarter of 2007 to establish the safety and efficacy of this novel cytotoxic conjugate. The study will be conducted as an "all comers" trial, so that accrual can be expedited, and a range of responses obtained. Approximately 40-50 patients with an advanced epithelial cancer that is EpCAM positive will be eligible to enroll.

VB6-845 has demonstrated effective cancer cell killing properties in pre-clinical tests. A full array of animal efficacy studies and safety studies of VB6-845 for the treatment of ovarian cancer and other solid tumors has been completed. In animal xenograft studies, VB6-845 elicited 100% complete cures of established ovarian tumors. VB6-845 has been shown to be safely tolerated in both primate and rodent animal safety studies.

NP-1 and Viventia’s antibody discovery engine

Viventia is developing a second generation portfolio of Armed Antibody(TM) products consisting of antibodies obtained from its proprietary antibody generation technology that are then conjugated to its proprietary bouganin protein. NP-1 is the first anti-cancer drug candidate selected from this antibody library and will begin preclinical development in 2007. NP-1, like all antibodies generated by Viventia, is human in origin and binds to a target found specifically on the surface of cancer cells.

Viventia’s antibody generation technology, based upon isolating antibody-producing immune cells from cancer patients, is unique and differentiated from other approaches. This approach yields antibodies that have been raised by the human immune system against a patient’s cancer. As such, they have a unique signature and often are found to bind to targets on the cancer cell that are different from those typically pursued by other companies. Hence, in essence, Viventia’s approach finds both novel targets and the human antibodies that bind to these targets.

About Viventia Biotech:

Viventia Biotech Inc. is a biopharmaceutical company developing Armed Antibodies(TM), powerful and precise anti-cancer drugs that combine cytotoxic protein payloads with the highly precise tumor-targeting characteristics of monoclonal antibodies to overcome various forms of cancer. Viventia’s lead product, Proxinium(TM), is undergoing a global Phase III clinical trial for the treatment of head and neck cancer. Viventia is also developing Vicinium(TM), which is entering into a Phase II clinical study for the treatment of bladder cancer. The Company has created a portfolio of follow-on antibody-based drug candidates and has a discovery engine to provide a rich and sustainable long-term pipeline.

SOURCE: Viventia Biotech Inc.