Anagrelide is an orally active imidazole-quinazoline compound that has been approved for the therapy of essential thrombocytosis, a rare blood disease with an annual incidence of about 2.5/100,000. Anagrelide is a phosphodiesterase 3 enzyme selective compound, which inhibits proliferation and maturation of megakaryocytes to thrombocytes. We have discovered that anagrelide also kills efficaciously GIST cells.

Experience with anagrelide in essential thrombocytosis therapy has shown that its long-term administration to patients is safe. Anagrelide is also safe to administrate together with the Glivec®, the first-line therapy option for many GIST patients.