CANCER

One in three people will be diagnosed with cancer during their lifetime and around one in five will die from it. Cancer is the major cause of death in the developed world. Although earlier diagnosis and the introduction of new and/or improved treatments have led to dramatic increases in survival rate for certain types of cancer, for most common malignancies there remains a great need for the development of more effective therapies. The increasing cancer incidence associated with the aging population adds to this need.

Surgery is the most effective modality in the treatment of solid tumours. However, many cancers have already infiltrated the surrounding normal tissues or disseminated to other parts of the body before diagnosis. Radiotherapy is also effective, when used either as a single modality or in combination with surgery, in the control of primary tumours but is less able to eradicate disseminated disease. Theoretically, chemotherapy has the greatest potential in the treatment of disseminated disease because systemically administered drugs can conceivably gain access to the entire body. The Achilles heel of chemotherapy is that its selectivity for cancer cells relies primarily on the fact that malignant cells multiply faster than most normal tissue cells. However, some normal cells, particularly those in the bone marrow and intestines, also divide rapidly and may thus be killed by chemotherapeutic agents, giving rise to toxicities that ultimately limit the effectiveness of treatment. Moreover, to elicit cures, the drugs have to reach and kill essentially all the clonogenic cells in a tumour. This is a formidable task if one considers that even a small tumour deposit, 1 cm3 in size, consists of over 1,000 million cells.

A major cause of treatment failure of both radiotherapy and chemotherapy is a population of tumour cells that is not well served by the tumour vasculature. These cells are hypoxic, are more resistant to treatment and can repopulate the tumour after other cells have been killed. Angiogene has developed two major technologies, VASCULAR DISRUPTING AGENTS and TUMOUR TARGETED PRODRUGS that target this resistant region of solid tumours and which could lead to major advances in chemotherapy. A third proprietary technology, NOS INHIBITION, has shown promise in the potentiation of vascular disrupting effects.

The oncology market is the third largest pharmaceutical market, worth an estimated $40 billion in 2004, and is currently experiencing strong growth. In 2004, the top 20 cancer drugs in each of the seven major pharmaceutical markets generated combined sales exceeding $27 billion.

OCULAR NEOVASCULARISATION

Ocular neovascularisation is a major cause of severe vision loss and blindness in the developed world. Pathological angiogenesis can occur in various tissues of the eye, including the choroids, the retina and the cornea.

Choroidal neovascularisation leads to the wet form of age-related macular degeneration (wet AMD). In the United States alone, more than 1.6 million people suffer from the active blood vessel growth and blood vessel leakage associated with wet AMD and approximately 200,000 new cases arise each year. Since the incidence of wet AMD rises sharply with age the number of sufferers is expected to increase with the expected aging of the population.

Retinal neovascularisation occurs in the proliferative phase of diabetic retinopathy. Most diabetes patients develop retinal changes after around 20 years. Blood vessel growth leads to leakage of blood into the retina and vitreous, impairing vision. In the later stages continued abnormal vessel growth and scar tissue may cause serious problems such as retinal detachment and glaucoma. There are around 65000 new cases of proliferative diabetic retinopathy each year in the United States.

Corneal neovascularisation is the ingrowth of abnormal blood vessel into the cornea from the limbus (junction of cornea and eye-white) and occurs as a complication of contact lens use.

Angiogene is exploring the use of its VASCULAR DISRUPTING and NOS INHIBITION technologies in the treatment of these diseases.

All images and text © Angiogene Pharmaceuticals Ltd. Last updated July 15th., 2007