Malaria infects 300–500 million people and causes 1-2 million deaths each year, primarily children in Africa and Asia. One of the principal obstacles to addressing this global health threat is a lack of effective, affordable drugs. The chloroquine-based drugs that were used widely in the past have lost effectiveness because the Plasmodium parasite which causes malaria has become resistant to them. The faster-acting, more effective artemisinin-based drugs — as currently produced from plant sources — are too expensive for large-scale use in the countries where they are needed most. The Keasling laboratory engineered both Escherichia coli and Saccharomyces cerevisiae to produce a precursor to artemisinin, artemisinic acid, which can be readily converted into artemisinin. Microbial production of artemisinic acid will eventually reduce the cost of artemisinin-based combination therapies significantly below their current price and stabilize the supply of artemisinin while controlling access. Our partner in this work was Amyris Biotechnologies, a company founded to develop and optimize this technology. Sanofi licensed the technology and scaled it. They began shipping artemisinin combination therapies containing artemisinin produced using this microbial production process in August, 2014. As of May 2015, they had shipped 15 million treatments to Africa.
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