The University of Hong Kong Faculty of Medicine has unveiled a new oral formulation of arsenic trioxide for the treatment of acute promyelocytic leukaemia, otherwise known as APL.

APL is a blood cancer that occurs suddenly with a high fatality rate, leading to bone marrow dysfunction and increased risk of infections and bleeding.

The new treatment, called Oral-ATO, obviates the need for chemotherapy and bone marrow transplant, which decreases the relapse rate.

Clinical Associate Professor at HKU, and the study's lead investigator, Dr Harinder Gill, said that with all abnormal cells gone, around one percent of patients under this treatment experience a relapse.

"So most of these patients are essentially cured with this oral formulation," he said.

Moreover, patients who take this new treatment do not need to be hospitalised and can just go to an out-patient clinic to collect medications after the initial diagnosis, allowing them to retain a normal life.

The production cost for this new oral formula is also much lower than traditional treatments, hence it is currently free and available at all hospitals in Hong Kong.

"But since this is an uncommon form of acute leukaemia, we would have this treatment centralised at Queen Mary Hospital and the University of Hong Kong where these patients would receive meticulous initial supportive care to reduce the early death rate," Dr Gill added.

Oral-ATO has obtained orphan drug designation from US Food and Drug Administration and the European Medicines Agency.

The research was done in collaboration with experts from around Asia, as well as teams from the UK and the US.