Generex Biotechnology Corporation announced completion of enrollment of the Antigen Express Inc. AE37 breast cancer immunotherapy trial. The clinical trial is designed to assess the ability of AE37 to reduce the risk of relapse in patients who have had breast cancer. While a pre-planned primary efficacy analysis is underway, completion of enrollment sets the time-point for the end-of-trial analysis, scheduled to be conducted one year's time.

The Phase II trial has enrolled over 300 patients at 15 sites in the US and Europe, making it the larger controlled, randomized, and single-blinded world-wide breast cancer vaccine study conducted to date. Patients enrolled in the trial have been previously diagnosed with node-positive or high-risk node-negative breast cancer and have received standard of care therapy. They were enrolled at the early stages of disease with the intent to establish the ability of AE37 to reduce the incidence of relapse.

An interim analysis conducted on data obtained through October of 2011 showed a strong trend suggesting that this was indeed the case. AE37 is a synthetic, off-the-shelf therapeutic vaccine designed using a fragment of the HER2 protein together with a proprietary modification developed using the technology platform of Antigen Express. The modification has been shown to activate CD4+ T helper cells, which are critical in the development of an immune response, in a HER2-specific manner.

In addition to CD4+ T cell activation, immunological studies of treated patients show a reduction of immune-suppressor cells, suggesting that the Antigen Express modification may have multiple modes of action. Based on results from the interim analysis conducted previously, the company was given a green light by the FDA to proceed with submission of a Phase III protocol. That study has been designed to focus on patients with low levels of expression of the HER2 protein who are not eligible to receive Herceptin.

This population of breast cancer patients is nearly double that which is eligible for Herceptin treatment and thus represents an area of significant unmet need and an untapped market segment.