NextBillion - An Initiative of the William Davidson Institute at the University of Michigan

Wednesday, April 5, 2017

It took a public-health disaster for the Zimbabwean government to recognize the power of precision medicine. In 2015, the country switched from a standard three-drug cocktail for HIV to a single-pill combination therapy that was cheaper and easier for people to take every day. The new drug followed a World Health Organization recommendation to incorporate the antiretroviral drug efavirenz as a first-line therapy for public-health programmes. But as tens of thousands of Zimbabweans were put onto the drug, reports soon followed about people quitting it in droves.

Collen Masimirembwa, a geneticist and founding director of the African Institute of Biomedical Science and Technology in Harare, was not surprised. In 2007, he had shown that a gene variant carried by many Zimbabweans slows their ability to break down efavirenz¹. For those with two copies of the variant — about 20% of the population — the drug accumulates in the bloodstream, leading to hallucinations, depression and suicidal tendencies. He had tried to communicate this to his government, but at the time efavirenz was not a staple of the country’s HIV programme, and so the health ministry ignored his warnings.

Masimirembwa continued to publish his research, but the authorities took no heed until there was trouble. A lot of confusion could have been avoided if the government had listened, he says, “It’s not a bad drug. We just know it can be improved in Africa.”

Masimirembwa is a rare breed. Although scientists worldwide have been pushing for ways to improve health care by tailoring diagnostics and treatment to the environment, lifestyle and genes of individual patients, few researchers have taken this precision-medicine approach in Africa.