After many years of research, there’s still no effective vaccine for malaria, a parasite that kills hundreds of thousands yearly in Africa and Asia. But scientists have figured out a way to mass-produce the most effective treatment at industrial scale using a genetically engineered strain of baker’s yeast. The study was published in Nature and funded by the Bill & Melinda Gates Foundation through nonprofit drug developer OneWorldHealth.

"It's the volatility that really makes the supply chain... just a complete train wreck."

The anitmalarial artemisinin is currently produced using artemisinic acid farmed from the soft wormwood tree, and as a result, prices can vary wildly between $350 and $1250 per kilogram as supply fluctuates based on crop yields and other factors. The yeast strain used in the study was engineered by a biotech startup called Amyris, whose chief scientific officer Jack Newman tells NPR, "It's the volatility that really makes the supply chain for this life-saving drug just a complete train wreck." It's hoped that augmenting existing production of artemisinin with the new semi-synthetic version can fill shortages in supply without distorting the market price, so as not to impact farmers in China, Vietnam, and elsewhere.

Scientists have been exploring the baker's yeast approach for years, but previous methods have only been able to produce weak artemisinic acid solutions of about 1.6 grams per liter. In contrast, the newly-published study cranks that to 25 grams per liter, for the first time enabling real industrial-scale production. French pharmaceutical Sanofi has already begun producing artemisinin using the method, churning out nearly 40 tons of the chemical, which it plans to increase to 60 tons next year, reports MIT Technology Review. The development probably won’t lead to a big decrease in the cost of malaria medicine overnight, but the team writes that all intellectual property rights to the process are being provided free of charge, and the ultimate goal is to make cheap antimalarials available wherever they're needed.