United States of America - The Food and Drug Administration has approved arsenic trioxide (Trisenox®) for the treatment of patients with acute promyelocytic leukaemia who have not responded to first-line therapy with transretinoic acid and anthracycline-based chemotherapy.

Acute promyelocytic leukaemia is a cancer of the white blood cells characterized by a rapid accumulation of abnormal white blood cells in the bone marrow and blood resulting in anaemia, susceptibility to infections, bleeding and haemorrhage.

Arsenic-containing preparations have been in medical use for more than 2000 years and interest in arsenic-based therapy was revived by reports of anti-leukaemia activity of some traditional Chinese preparations.

Arsenic trioxide can cause an increase in the QT interval and lead to arrhythmia. Other adverse effects include abdominal discomfort, nausea, vomiting, headache, fatigue, skin changes, and fluid accumulation. These were considered mild and resolved after therapy was completed.

Reference: FDA Talk Paper, T00-47 (2000).