Recent developments in antiangiogenic therapy.

The use of antiangiogenic therapy is gaining momentum as a novel treatment for a number of conditions, ranging from cancer to psoriasis. This has stemmed from research in the early 1970s showing that the formation of new blood vessels by pre-existing endothelial cells is essential in tumour growth and progression. However, although antiangiogenic therapy was hailed as a new avenue of treatment for cancer, initial clinical data have been disappointing. This has led to the reassessment of antiangiogenic therapy for cancer, and new strategies have been proposed to increase the efficacy of these agents in this setting. Angiogenesis has also been implicated in other conditions that are notoriously difficult to treat, such as arteriosclerosis, arthritis, psoriasis and diabetic retinopathy. Increased understanding of the angiogenic process, the diversity of its inducers and mediators, appropriate drug schedules and the use of these agents with other modalities may lead to radically new treatment regimens for many of these conditions. The role of angiogenesis in different pathological settings, and emerging antiangiogenic agents currently in preclinical and clinical studies are discussed in this review. However, while potential benefits are profound, limitations of antiangiogenic therapy have also been identified, suggesting that there is also a need for caution in applying these compounds to the clinical setting.