Wits University researchers turn cashew waste into vaccine breakthrough

Nokukhanya Mntambo, standing in for 702's Gugs Mhlungu, spoke to Professor Patrick Arbuthnot, Head of The Antiviral Gene Therapy Research Unit at Wits University.

Listen to their conversation in the audio clip below.

Cashew nuts may be a healthy snack, but their shells (usually discarded and inedible) could now help Africa make its own vaccines. 

Wits University researchers have scored a major international win, a R7-million grant, to turn leftover cashew nutshell liquid into key ingredients for mRNA vaccines.

"These shells of cashew nuts contain a liquid that is rich in some quite rare lipids or fats that can be processed to form a precursor, a feedstock that can be used to make the ionisable lipids that go into the formulations for making mRNA vaccines."

- Professor Patrick Arbuthnot, Head of The Antiviral Gene Therapy Research Unit at Wits University

According to Arbuthnot, Africa produces over half of the world’s cashew nutshell waste, and until now, most of it has been thrown away.

He says the cost of making these ionisable lipids from cashew nut shell liquid is about a tenth of the price of the licensed ionisable lipids in commercial vaccines.

Arbuthnot adds that these ionisable lipids are usually made from petroleum products, so using cashew waste is “a very important green development.”

"Something that people don't realise is that about 95% of all drugs are made from petroleum products. So if you go to a pharmacy and collect your prescription for whatever it might be, those drugs are made from petroleum products...not many people actually appreciate that and it's not good for the environment because the process of making the drugs entails the use of very hazardous compounds, solvents, etc, and they're also byproducts of that process of cracking the petroleum products to generate the pharmaceutical precursors." 

- Professor Patrick Arbuthnot, Head of The Antiviral Gene Therapy Research Unit at Wits University

The breakthrough project, explains Arbuthnot, could be a game-changer in reducing costs and boosting Africa’s ability to produce its own vaccines, with the African Union targeting 60% local vaccine production by 2040.

This innovation, notes Arbuthnot, puts Wits and South Africa at the forefront of vaccine-related bio-innovation on the continent, showing how homegrown science can tackle global health challenges.

"It would certainly help the African continent to deal with its own problems...mRNA vaccines have got huge potential, not only for COVID, but all sorts of other pathogens, disease pathogens, and also cancer, potentially treated with mRNA vaccines. So it's a very important development to enable Africa to deal with its own problems." 

- Professor Patrick Arbuthnot, Head of The Antiviral Gene Therapy Research Unit at Wits University

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