2015 Nobel Prize in Physiology/Medicine: Discovery of Ivermectin and Artemisinin against Tropical Parasites

It has been a rather rare event that the Nobel Foundation gave an award to biomedical scientists who contributed to either discovery or development of antibiotics (herbal remedy) such as penicillin and streptomycin.  Nevertheless, this year three scientists are going to share a Nobel prize in physiology/medicine for their discovery/development of ivermectin and artemisinin which kill tropical parasites such as malaria and pathological nematodes.  Youyou Tu (85) in China who discovered an anti-malaria herbal compound called artemisinin in 1970s shares a half of this prize, while Satoshi Omura (80) at Kitasato Institute in Japan and William Campbell (85) at Drew University in US, who discovered/developed an anti-nematode antibiotic called ivermectin in 1980s, share the remaining half of this prize. 

Quite interestingly, both artemisinin and ivermectin are PAK1-blockers, and are well known to suppress the growth of cancers, and many other PAK1-dependent diseases/disorders.  However, ivermectin appears not to pass BBB (blood brain barrier), and therefore would be useless for the therapy of brain tumors and neuronal diseases such as AD (Alzheimer’s disease).  Although the IC50 of artemisinin (AM) against cancer cells in cell culture is rather high, very recently a far more potent AM derivative was developed by a German group. This AM derivative kills cancer cells with IC50 around 10 nM (1). Thus, in the future, not only people living in tropical zones, but also those in the remaining areas could have a significant benefit from this potent anti-cancer AM derivative. 

References:

1.  Reiter C¹, Fröhlich T¹, Zeino M², Marschall M³, Bahsi H³, Leidenberger M⁴, Friedrich O⁴, Kappes B⁴, Hampel F¹, Efferth T⁵, Tsogoeva SB⁶. New efficient artemisinin derived agents against human leukemia cells, human cytomegalovirus and Plasmodium falciparum: 2nd generation 1,2,4-trioxane-ferrocene hybrids. Eur J Med Chem. 2015 ; 97:164-72.