R21 anti-malaria vaccine is a game changer: scientist who helped design it reflects on 30 years of research, and what it promises
Until three years ago nobody had developed a vaccine against any parasitic disease. Now there are two against malaria: the RTS,S and the R21 vaccines. Adrian Hill, director of the Jenner Institute at the University of Oxford and chief investigator for the R21 vaccine, tells Nadine Dreyer why he thinks this is a great era for malaria control.What makes malaria such a difficult disease to beat?Our hominoid predecessors were being infected by malaria parasites tens of millions of years ago, so these parasites had a lot of practice at clever tricks to escape immune systems long before we came along.
Until three years ago nobody had developed a vaccine against any parasitic disease. Now there are two against malaria: the RTS,S and the R21 vaccines. Adrian Hill, director of the Jenner Institute at the University of Oxford and chief investigator for the R21 vaccine, tells Nadine Dreyer why he thinks this is a great era for malaria control.
What makes malaria such a difficult disease to beat?
- Our hominoid predecessors were being infected by malaria parasites tens of millions of years ago, so these parasites had a lot of practice at clever tricks to escape immune systems long before we came along.
- Additionally, the malaria parasite goes through four life cycle stages.
- Medical researchers have been trying to make malaria vaccines for over 100 years.
How does the R21/Matrix-M vaccine work?
- An antigen is any substance that causes the body to make an immune response against that substance.
- We targeted the sporozoites, which is the form that the mosquito inoculates into your skin.
- Read more:
Two new malaria vaccines are being rolled out across Africa: how they work and what they promise
A child dies every minute from malaria in Africa. Why are children more susceptible than adults?
- The age you’re most likely to die of malaria in Africa is when you are one year old.
- For the first six months you are protected largely by your mother’s immunity and the antibodies she transfers during pregnancy.
- Without malaria, children would be healthier in general — the disease makes you susceptible to other infections.
What about the pace of vaccine rollouts?
- We’ve been disappointed that it’s taken more than six months to roll out the R21 vaccine since it was approved in October last year.
- Compare that to a COVID-19 vaccine from Oxford and AstraZeneca that was approved on New Year’s Eve 2020 and rolled out in several countries the very next week.
How big a role will vaccines have in the fight to eradicate malaria?
- Nobody is quite sure how many of the older tools such as insecticides and bed nets we need to carry on with.
- Anti-malaria medication only lasts for days and parasites are building up resistance against these drugs as well.
- There are about 40 million children born every year in malaria areas in Africa who would benefit from a vaccine.
- The Serum Institute of India, our manufacturing and commercial partner, can produce hundreds of millions of doses each year.
Adrian Hill receives funding from government and charitable funders of malaria vaccine development. He has received funding awarded to the University of Oxford from the Serum Institute of India to support clinical trials of the R21/Matrix-M vaccine. He may benefit for a share of any royalty stream to Oxford University from the vaccine.