Malaria is estimated to kill as many as 400,000 people a year, mostly children in Africa. But despite years of work no truly effective vaccine against the disease has been developed. But yesterday researchers published a preprint of trial results from Burkina Faso which showed a new vaccine was 77% effective.

The results come from a small trial of a vaccine developed by researchers at the University of Oxford’s Jenner Institute involving 450 toddlers in Burkina Faso, where malaria is endemic.

“The efficacy we have got has never been obtained by any [malaria] vaccine candidate. These are really amazing findings,” says Halidou Tinto, a parasitologist at the Institute for Health Sciences Research in Nanoro, Burkina Faso, and a principal investigator at the site of the study…

The children in the current trial, aged 5 months to 17 months, received three doses of vaccine at 4-week intervals and a booster dose at 12 months. Of the 146 children who received  vaccine containing a high dose of an immune-boosting compound called an adjuvant, 38 developed malaria, versus 105 of 147 children in a control group who received rabies vaccine. (That protocol ensured the control group also received value from being in the trial.)

Prior to this, the most effective vaccine developed to fight malaria was just 55% effective. The current plan is to begin a large phase 3 trial later this year involving nearly 5,000 children. If that is safe and effective, the data would be submitted to regulators sometime next year. That could means hundreds of millions of doses would be available by 2023. However, if regulators offer an emergency use authorization, as they did for the coronavirus vaccine, then doses could be available even sooner.

The malaria vaccine has taken so much longer to develop because it’s much more complicated than the coronavirus:

A malaria vaccine has taken much longer to come to fruition because there are thousands of genes in malaria compared to around a dozen in coronavirus, and a very high immune response is needed to fight off the disease.

“That’s a real technical challenge,” Prof Hill said. “The vast majority of vaccines haven’t worked because it’s very difficult.”

The bottom line is we’re still at least a year away from deploying this but if the phase 3 trial shows similar results it could save the lives of hundreds of thousands of children a year and potentially spare tens of millions of adults from the misery of a malaria infection.

Here’s a VOA report on the new findings.