Nature News examines how scientists, farmers are working to meet the growing demand for artemisinin

"From bust to boom to bust again: artemisinin, the key ingredient of front-line antimalarial drugs, is entering the third chapter of its turbulent history," Nature News writes in an article that examines the challenges scientists and farmers are facing as they attempt to keep up with the growing demand for the compound just as a "$343-million initiative starts to battle malaria through hugely subsidized medicines."

The article describes how the Affordable Medicines Facility-Malaria (AMFm) initiative - a program within the Global Fund to Fight AIDS, Tuberculosis and Malaria designed to help reduce the price of artemisinin-based combination therapies (ACTs) - is driving artemisinin demand. Though "[g]overnmental public-health clinics already offer ACTs at just $1 per dose, ... roughly 60% of patients with malaria opt for convenience and buy the drugs from local market stalls and private pharmacies - even though they cost many times more," according to Nature News. "The AMFm initiative, running as a two-year trial in seven African countries and in Cambodia, hopes to ensure that even the private sector will sell ACTs at $0.20-0.50 per dose. That should improve access to the drugs, and may stop patients buying cheap but ineffective chloro­quine or the single artemisinin therapies that are promoting resistance. It will also drive up demand for artemisinin." However, as the article continues, "Artemisinin suppliers have seen this all before," citing a 2005 declaration by the WHO that more of the compound was needed to ramp of ACT production.

The article describes how synthetic biologists responded to the WHO's appeal by searching for ways to coax bacteria and yeast into producing the precursor of artemisinin, highlighting the work of the University of California at Berkeley's Jay Keasling. His "semi-synthetic artemisinin project received $42.6 million over five years from the Bill & Melinda Gates Foundation, and became a focus for biotech firm Amyris of Emeryville, California, which spun out from Keasling's lab. It successfully added or tweaked a dozen genes in yeast to make artemisinic acid … and gave a royalty-free licence to drug firm Sanofi-Aventis … to make semi-synthetic artemisinin on a commercial scale," the journal writes. "Four years on, the product is still two years away, says the drug company, which is scaling up production to 100,000-litre vats," according to the article.

Farmers in China and Vietnam also responded to the increased demand for the compound by planting "tens of thousands of hectares of Artemisia," Nature News writes. By 2007, the journal writes, "the market was swamped," leading the price of artemisinin to drop dramatically "from more than $1,100 per kilogram to around $200 per kilogram." As a result, processing companies and farmers found themselves out of business, according to Nature News.

"Even though artemisinin was being sold cheaply (compared with the price that Sanofi-Aventis will set in 2012), millions of people in sub-Saharan Africa were still not getting access to the ACTs," Nature News writes. "We have learned there is a lot more to it than cost," Jack Newman, co-founder and senior vice-president for research at Amyris, said. "Improving access to the medicines is as important as driving down their price - hence the idea for the AMFm, and its focus on the local businesses that sell treatments," the journal adds.

Drawing upon comments by Keasling and Malcolm Cutler, an artemisinin-industry expert, the article details some of the lessons scientists and farmers learned from the 2005 call to ramp up artemisinin production that can be applied to help meet future demand for the compound (Van Noorden, 8/3).