Reto Brun is one of the most productive and most highly cited scientists at the University of Basel. He was instrumental in developing new drugs to treat human African trypanosomiasis (sleeping sickness) and malaria. To mark his retirement, the Swiss Tropical and Public Health Institute (Swiss TPH) was staging a half-day public farewell symposium in his honour.
What Reto Brun really wanted to be was an inventor. As a small boy, he made all kinds of things himself: a candle snuffer for the Christmas tree or firework rockets that projected colourful sparks into the night sky. Until he had to accept, with some disappointment, that you cannot earn a living as an inventor. In the late 1960s, Brun studied biology at the University of Basel. He wanted to do a doctoral thesis and approached Rudolf Geigy, who was the director of the Swiss Tropical Institute at that time. He suggested that the 22-year-old study insect flagellates in blowflies in East Africa. The similarity between these living organisms and Trypanosoma, the pathogen of sleeping sickness, is striking. “At least I was not deterred by the idea of travelling to Africa”, says Brun quietly.
The end of the world has a name: Tororo, Uganda. A research centre for human African trypanosomiasis. Reto Brun caught flies, dissected their intestines, and examined them
for infections with flagellates. And he developed new nutrient media in order to breed these flagellates under laboratory conditions. “The major problem was that breeding
flagellates had to be done under sterile conditions”, Brun remembers. His inventive talent was in demand. He made a box with a burning UV lamp inside in which he could manipulate his test objects until his eyes hurt. The flagellates developed very quickly and Brun continued his experiments. Later he also succeeded in breeding sterile flies, which he then infected with flagellates.
New drugs to treat sleeping sickness and malaria
After the successful completion of his doctoral thesis and a post-doctorate at the University of California, Irvine, Brun returned to the Swiss Tropical Institute. There he devoted himself to what he liked doing most: developing new nutrient media for various forms of the sleeping sickness pathogen. His work on the cultivation of Trypanosoma brucei published in 1979, ranks third in the list of the most cited works since 1900, according to the Web of Science. This and other articles laid the foundation stone for the successful development by Swiss TPH of new drugs to treat sleeping sickness and malaria. The highly promising new active agent to treat the former is called fexinidazole. The molecule comes from the compound library of the Drugs for Neglected Diseases initiative (DNDi), one of the three big public-private part-
nerships in Geneva. Researchers at Swiss TPH proved its efficacy in animal models and clinical trials in the Congo. The major benefit: fexinidazole can be taken as a tablet and is safe for patients. “Fexinidazole will speed up the eradication of this horrible disease”, says 71-year-old Brun. The active substance is expected to be given marketing authorisation before the end of the year. Asked whether he was proud to have played a major role in the development of this
new drug to treat this centuries-old scourge, Reto Brun makes a dismissive gesture. The much-cited scientist is not someone who likes to blow his own trumpet. “Success is never the work of just one person. The development of new drugs, in particular, is all down to team work.”
Already in the 1980s, Reto Brun encouraged cooperation with African partner institutions. Together with organisations in Uganda and Kenya, he made a major contribution to the establishment of the Eastern Africa Network for Trypanosomosis (EANETT). The aim of the network is to control sleeping sickness and to promote the training of young African researchers. Today, EANETT has been integrated into DNDi. “At the beginning of my career, I always said that I wanted to play an important part in developing drugs to treat
neglected tropical diseases”, says Brun. He has certainly achieved that goal.