Dwight Sipler/small farm
Worcester Polytechnic Institute biology student, Hillary Cirka, bagging harvested plants for drying in 2012.
Since June, dozens of plants with lacy, fern-like leaves have been growing on a patch of land at Small Farm in Stow. The bushy, towering plants look a lot like weeds gone wild, but they are far from a farmer’s scourge; instead, the neatly-planted rows are part of a scientific experiment that may lead to a cheaper and more effective way to treat one of the world’s biggest public health problems.
For decades, scientists have known that a chemical called artemisinin is an effective treatment for malaria, which killed 660,000 people in 2010, according to the World Health Organization. To produce a malaria drug, however, scientists must isolate the chemical from the Artemisia plant through a multi-step process and then combine it with other antimalarial medications, to reduce the risk the malaria parasite will develop resistance to the drug. All that takes time and money, and a portion of the precious chemical is inevitably lost during the processing.
Intrigued by the casual use of the whole Artemisia plant as an herbal therapy and tea for a range of illnesses, Pamela Weathers , a professor of biology and biotechnology at Worcester Polytechnic Institute, began to wonder if it might be possible to treat malaria more directly, using just the dried and powdered leaves of the plant.
Her early work suggested that the strategy would work, and that the plant even contained other substances in its leaves that could increase the uptake of artemisinin into the bloodstream, perhaps making it more potent. Two years ago, she began planting the crop in a landscape more often associated with apple orchards, and studying its effects.
“This is really something where people in developing countries are dirt poor, and the drugs they do get nowadays are all paid for and subsidized by western companies and lots of big pharmaceutical companies are involved in the preparation and sale of drugs,” Weathers said. “In developing countries, they could grow this plant and process it into tablets themselves, very extensively.”
Last year, she and collaborators at the University of Massachusetts at Amherst published a study in the journal PLOS ONE showing that when administered to mice infected with the malaria parasite, the dried, powdered leaves were even more effective than an equivalent dose of the pure, isolated active ingredient.
With this year’s crop, Weathers hopes to figure out how to increase the yield of the plant as well as continue basic scientific studies of the drug so that she can figure out better how it works and how it compares to standard treatments. She espeically hopes to understand how the other compounds found in the plant may improve the effectiveness of the treatment, in part by studying genetically tweaked plants that don’t make artemisinin at all.
Weathers describes herself as a person who looks for “short tunnels”—ways for science in the laboratory to have a direct impact on the real world soon. She is applying for funding to support a pilot study of growing the crop in Uganda, and believes that with the right support, tablets made from dried leaves could be tested in people within a few years.
“It’s being used already in a lot of places in Africa as a tea, so people are self-medicating and the unfortunate problem is they have no idea what they have,” Weathers said. “We’d like to standardize and control that—so it’s a known cultivar, a known amount of material, we’d add a simple quality control test.”