A research team at the Department of Medicine, The University of Hong Kong Li Ka Shing Faculty of Medicine and Queen Marry Hospital (QMH) has spent a decade developing oral arsenic trioxide from a research project to a prescription medication that has secured a US patent. For the first time, a drug developed entirely in Hong Kong is poised to attain global status as a prescription medication. More than a hundred leukaemia patients in Hong Kong have been treated, the majority being cured by this novel drug. The work has been done by a small team of medical researchers, with the achievement based on ingenuity, meticulous work and diligence - a typical Hong Kong success story of innovation. This work is a historic landmark in medicine in Hong Kong.

- Clinical applications of oral arsenic
The team has shown oral arsenic to be a safe drug. With appropriate dosing, the potential toxic effects of arsenic, particularly toxicity to the heart, have been overcome. Oral arsenic has been shown to be highly active in acute promyelocytic leukaemia, and has now become a standard in the initial treatment of some patients, in the continuous treatment of patients in remission, and for patients in relapse. More than 100 patients have since been treated, with excellent results. The use of oral arsenic has replaced bone marrow transplantation as the standard treatment for these patients. Oral arsenic has also been used in the treatment of other blood cancers, including lymphomas and myeloma.

The research team and Veristech Limited, the technology transfer company of The University of Hong Kong, have secured a US patent for the use of oral arsenic trioxide in the treatment of blood cancers in 2009. This is a historic event for two reasons. Oral arsenic is the first prescription drug ever to be developed in Hong Kong. It is also the first prescription drug in Hong Kong to secure a US patent.

- Background and development history
Oral arsenic was used in the Department of Medicine, QMH, for patient treatment in the late 1940s and early 1950s. However, newer drugs phased out oral arsenic, and its use was forgotten for nearly half a century. In 1998, a small team of medical researchers at QMH, began investigating the use of oral arsenic in the treatment of blood cancers, based on the successful use of intravenous arsenic trioxide in the treatment of acute promyelocytic leukaemia, first discovered in Harbin and verified in Shanghai.

To determine the dosage and safety of oral arsenic, the research team initially turned to archival medical records retrieved from the Hong Kong Medical Museum. This was followed by two years of research into the method of preparation of the oral formulation. In 2000, the team successfully prepared an oral formulation of arsenic that was tested in a clinical study in blood cancer treatment. With demonstrated clinical efficacy, the research team in collaboration with Versitech Limited, filed an application for a US patent.

- Global perspectives
With oral arsenic protected by intellectual property rights, Versitech will work on the global distribution of oral arsenic. On March 26, 2010, medical researchers and doctors from North America, Europe, Africa, Australia and Asia came together in Hong Kong for the first international meeting organized by Hong Kong Society of Haematology on oral arsenic. The conference focused on the discussion of global academic collaborations to further define the use of oral arsenic in the treatment of various malignant and non-malignant diseases.

- Humanitarian perspectives
Arsenic trioxide is available as an intravenous drug in the US. The cost is about 50,000 US dollars (400,000 HK dollars) a month. The prohibitive cost makes this potentially life-saving medication out of reach of leukaemia patients in developing countries. Oral arsenic is set to replace intravenous arsenic trioxide as the standard formulation. HKU is investigating the feasibility of making oral arsenic available on a compassionate basis to patients in developing countries, who face immense difficulties with drug costs, and the provision of in-patient hospital facilities and laboratory tests. Oral arsenic is very safe, and can be prescribed in the outpatient setting, obviating many of the medical problems in developing countries. A compassionate programme will save the lives of numerous underprivileged patients.

- Paradigm of innovation in the Hong Kong spirit
Oral arsenic has been developed by a small team of dedicated researchers from the Department of Medicine, HKU and the Pharmacy Department of QMH. It has taken years of hard work, without funding from any major government source. A combination of ingenuity, dedication, meticulous work, diligence and team work from doctors and patients has made the development of oral arsenic a success story true to the spirit of Hong Kong.

For more information, please visit the website at: 
http://www.med.hku.hk/hkumed/news_list.php?year=2010&month=Mar