Novel therapies against parasitic diseases win Nobel Prize

A novel therapy against infections caused by roundworm parasites has won William Campbell and Satoshi ?mura half of the 2015 Nobel Prize in Physiology or Medicine. The other half has been awarded to Youyou Tu for her discoveries concerning a novel therapy against malaria.

William Campbell and Satoshi ?mura developed the drug Avermectin which has been proven to radically lower the incidence of River Blindness and Lymphatic Filariasis, as well as an expanding number of other parasitic diseases. Youyou Tu discovered Artemisinin, a drug that has significantly reduced the mortality rates for patients suffering from malaria.

Satoshi ?mura, a microbiologist at the Kitasato University, Japan, focused on a group of bacteria known as Streptomyces, which lives in the soil and was known to produce a plethora of agents with antibacterial activities. ?mura successfully isolated new strains of Streptomyces from soil samples and cultured them. From many thousand different cultures, he selected about 50 of the most promising, with the intent that they would be further analysed for their activity against harmful microorganisms.

William Campbell from Drew University in Madison, US acquired ?mura’s Streptomyces cultures and explored their efficacy. He showed that a component from one of the cultures was remarkably efficient against parasites in domestic and farm animals. The bioactive agent was purified and named Avermectin, which was subsequently chemically modified to a more effective compound called Ivermectin. Ivermectin was later tested in humans with parasitic infections and effectively killed parasite larvae. Collectively, ?mura and Campbell’s contributions led to the discovery of a new class of drugs with extraordinary efficacy against parasitic diseases.

Youyou Tu from China Academy of Traditional Chinese Medicine used a compound from a traditional herbal medicine to tackle the challenge of developing novel malaria therapies. She used the plant Artemisia annua and extracted its active component. Tu was the first to show that this component, later called Artemisinin, was highly effective against the malaria parasite, both in infected animals and in humans. Artemisinin represents a new class of antimalarial agents that rapidly kill the malaria parasites at an early stage of their development, which explains its unprecedented potency in the treatment of severe malaria.

One half of the 8 million SEK (£0.6 million) prize goes to Youyou Tu; the other half is shared between William Campbell and Satoshi ?mura.

The awards were established in the will of Alfred Nobel in 1895, and first awarded in 1901. There have been 105 prizes awarded in physiology or medicine, won by 210 laureates.