Nobel prize for herb-based malaria drug

New-Malaria-Drug-Treatment-2Many of you likely heard about one of this year’s Nobel prize winners. Tu Youyou, a Beijing-based researcher, was awarded the prize for her role in extracting the malaria-fighting compound Artemisinin from the traditional Chinese herb, artemisia annua (青蒿 qing hao). It has been interesting attending a TCM university at the time when this announcement was made – every lecturer seems to have a different opinion about it.

Some scholars and doctors feel Professor Tu Youyou’s work had nothing to do with traditional herbal medicine, as taking an extract from a plant and making a drug from it is a Western biomedical approach. The Chinese traditional medical approach is to use the whole herb (e.g. the whole leaf, stem, root, etc.), almost always combined with a number of other herbs, in a formula customized for an individual person (not standardized for every person with the same disease). This is a key aspect of TCM practice known as 辨证论治 bian zheng lun zhi, or treatment based on differentiation of patterns. The synergistic combinations of chemical components in a single herb (some of which contain many known or potential active constituents), or combinations of herbs in a formula, are said to enhance positive actions of the herbs, balance potential side effects, promote better absorption by the body, and reduce toxicity. In other words, plants and formulas are greater than the sums of their parts. Many teachers at my university emphasize that traditional medicine is about treating the person, not the disease.

On the other hand, others feel that Professor Tu Youyou’s work does show the value of traditional knowledge of medicinal herbs. In this 2011 Nature article, Professor Tu herself recounts how she had to dig up an obscure instruction in a classical herb manual, before being able to effectively prepare the herb – and that previous attempts had all failed. So, some of my professors here feel her discovery reflects the need to respect empirical knowledge amassed by herbalists over the centuries.

Overall, the discussion may reflect differing opinions on how best to use plant-based medicines extract and standardize active components, even synthetically reproduce them? Or continue to use whole plant parts in their natural states?  Each approach has its benefits and drawbacks (though without question the bulk of research money goes into the former approach, which leads to patentable drug products).

In the case of Professor Tu and her team, they isolated an important medicinal compound, received no profits from it (they did not patent their discovery, as their research was state-funded), and have been duly recognized for their work. However, some herbalists and researchers are concerned that isolating components from plants leads to more pronounced side effects, and less efficacy in some aspects.  This study for example, shows that natural qing hao is more effective in combating drug resistance over the longer-term. The study’s abstract states:

“Pharmaceutical monotherapies against human malaria have proven effective, although ephemeral, owing to the inevitable evolution of resistant parasites… In 2012, we demonstrated the efficacy of the whole plant (WP)—not a tea, not an infusion—as a malaria therapy and found it to be more effective than a comparable dose of pure artemisinin in a rodent malaria model… The resilience of WP may be attributable to the evolutionary refinement of the plant’s secondary metabolic products into a redundant, multicomponent defense system. Efficacy and resilience of WP treatment against rodent malaria provides compelling reasons to further explore the role of nonpharmaceutical forms of AN to treat human malaria.”

In sum, while plant-derived drugs have provided many benefits to human health, patients may also greatly benefit from research into the actions and interactions of (non-patentable) whole-plant or complex-formula herbal research.