- An experimental vaccine from researchers at the University of Oxford and Maryland biotech Novavax was shown to be strongly effective against malaria, a promising finding against one of the world's most deadly diseases, according to pre-printed study results published with The Lancet on Friday.
- The shot was up to 77% protective in a Phase 2b study of 450 children 5 to 17 months old in the West African country of Burkina Faso. Protection remained strong after one year of follow-up, and the majority of side effects to vaccination were graded as mild. A Phase 3 study of about 4,800 participants between 5 and 36 months of age has begun in four African countries.
- The vaccine uses technologies from two teams who have each developed an effective coronavirus vaccine over the past year. Oxford's vaccine was licensed to AstraZeneca and has since been authorized in more than 50 countries, while Novavax's has succeeded in a large Phase 3 study. The malaria vaccine, R21, is being manufactured by the Serum Institute of India.
While much of the world's attention is focused on the rollout of vaccines to end the coronavirus pandemic, an effective shot against malaria — a disease contracted from a specific type of mosquito — has been a much longer-running quest and could play a huge role in improving public health.
There were 229 million malaria cases and over 400,000 deaths from the disease in 2019, and most of them occurred in children in sub-Saharan Africa, according to data from the World Health Organization. Drug resistance has played a key role in malaria's persistence, but so has the lack of a strongly protective shot.
Just one vaccine, known as RTS,S or Mosquirix and discovered by GlaxoSmithKline scientists, has shown an ability to prevent the disease in African children. But the vaccine, which was only recently introduced to three African countries, only provides partial protection. Studies found the shot is roughly 56% protective in 5 to 17 month olds after one year, and gets weaker over time. There have also been signs of possible safety signals, such as meningitis, associated with its use.
The WHO has been searching for a better answer — specifically, a vaccine that's both safe and more than 75% protective by 2030 — and, for the first time, it has a chance to reach that goal if the results of the study disclosed Friday are reproduced in further testing.
The vaccine is a joint effort between two of the major players in coronavirus vaccine development. Oxford, whose scientists developed AstraZeneca's vaccine, developed an antigen known as R21 that's used in the malaria shot. Novavax contributed its immune-boosting adjuvant Matrix-M, which is also featured in its coronavirus vaccine as well as a flu shot known as NanoFlu.
Study participants received R21 with either a low (25 milligram) or high (50 milligram) dose of Matrix-M, or rabies vaccines used as a control. The regimen included three shots and a fourth booster given after 12 months. The vaccine produced 71% efficacy with the low-dose adjuvant, and 77% at the high dose after one year, with no reported severe reactions. Redness, swelling and pain were the most common side effects.
"We believe this vaccine could have a major public health impact," said Adrian Hill, the co-author of the Lancet paper and the director of Oxford's Jenner Institute, which specializes in vaccine research, in a statement.
Much will depend on how long the shot's protective effects hold up. Study researchers noted that Mosquirix's effectiveness "waned considerably over time," falling to 36% after a median of four years. They attributed the weaker long-term results to the shot's inability to get protective antibodies to peak levels after a fourth booster.
Antibody levels after a fourth shot of R21, by comparison, are comparable to what was seen after three shots, suggesting "efficacy could be better maintained,” study authors said.
Follow-up is ongoing, as is a large Phase 3 trial to confirm the results. The manuscript has yet to be peer-reviewed.
India's Serum Institute, which is helping to produce AstraZeneca's vaccine, has said it can make 200 million doses available annually if the shot is approved by regulators. Novavax has rights to sell the vaccine in certain countries and would get royalties on sales of the shot in regions where the disease is endemic.
Novavax's coronavirus vaccine, meanwhile, is under review in Europe, Canada, Australia and New Zealand. It could seek emergency authorization in the U.S. this quarter if a Phase 3 study expected to produce results imminently succeeds. Shares climbed about 3% on Friday.