Pharmexa Plans Clinical Trials in the U.S.A and Releases New Data from Its AutoVac HER-2 Protein Breast Cancer Product


HARSHOLM, Denmark, May 21, 2002 (PRIMEZONE) -- Following a successful pre-IND meeting with the Food and Drug Administration (FDA) in the United States, Pharmexa has decided to conduct the first clinical trial with its AutoVac(TM) HER-2 Protein pharmaccine against breast cancer in the United States.

At a recent meeting with the FDA, Pharmexa presented its proposed clinical trial design, pre-clinical programme and manufacturing plan. Based on a very positive response from the FDA, Pharmexa is planning an Investigational New Drug application (IND) for a clinical trial in the United States. Pharmexa expects that the first clinical trial can be initiated in early 2003. The objective of the trial will be to evaluate the safety of the product, and the secondary objective to observe the level of HER-2 specific antibodies induced. As a result of the discussions with the FDA, Pharmexa has reasons to believe that progression to phase II will be faster than originally anticipated.

New data confirm promise

Pharmexa has previously published that a mouse analog of the AutoVac(TM) HER-2 Protein pharmaccine could successfully be used to treat established mouse tumours. Pharmexa has carried out further animal studies showing that antibodies induced by the AutoVac(TM) HER-2 pharmaccine are at least as effective as Herceptin(R) at controlling the growth of grafted human tumours in mice.

Additional new data from a recent pre-clinical study in monkeys shows that vaccination with the human AutoVac(TM) HER-2 Protein pharmaccine leads to antibody concentrations at anticipated therapeutic levels in all monkeys after only 2-3 vaccinations, indicative of a highly effective pharmaccine. This result holds a lot of promise for the coming clinical testing in humans.

These results confirm that AutoVac(TM) vaccination against the HER-2 protein is potentially an effective means of breast cancer therapy. The efficacy in humans of such therapeutic vaccination will likely depend on the nature of the tumour itself, its susceptibility to different host effector mechanisms and the robustness of the immune response. The AutoVac(TM) approach can be utilized with both DNA and Protein pharmaccines resulting in strong humoral and cellular immune responses, thus increasing the likelihood of therapeutic effect.

How does the AutoVac HER-2 Protein pharmaccine work?

The AutoVac(TM) HER-2 Protein pharmaccine works by stimulating the patient's own immune system to raise high antibody responses against the HER-2 protein. The HER-2 protein is a growth factor receptor present in many cancers, including breast, ovary, uterus, stomach, bladder, prostate, colon and lung cancers.

The HER-2 growth factor is found in up to 25% of breast cancers, and is usually associated with a poor prognosis for the patient. A number of treatment options exists against breast cancer, including the monoclonal antibody product Herceptin(R), which also works by targeting the HER-2 protein. This drug is in the process of achieving status as first choice treatment in the United States and generates annual sales exceeding 500 million dollars. Pharmexa believes that the AutoVac(TM) HER-2 Protein pharmaccine will offer important advantages over Herceptin(R) in terms of efficacy, safety, patient friendliness and health care costs. The HER-2 Protein pharmaccine is one of two Pharmexa pharmaccines targeting the HER-2 molecule. The other is the AutoVac(TM) HER-2 DNA pharmaccine that is designed to induce a cellular immune response. This pharmaccine is currently in phase I/II in the United Kingdom and Denmark.