Giving malaria victims a common blood-pressure drug along with regular treatment may save lives by preventing lethal brain hemorrhages, scientists reported on Monday.

The experiments were done only in infected mice and may not predict success in humans. But substantially more mice were saved when given the drug, according to scientists at NYU Langone Medical Center and their colleagues in Spain and Germany.

The study was published in The Journal of Clinical Investigation.

There are an estimated 216 million malaria infections around the world each year, and more than 400,000 deaths — mostly young children in Africa. Most of the fatalities, the authors said, were caused by cerebral malaria.

Parasite-filled red blood cells become “sticky” and clump together in the brain’s tiny capillaries, first jamming them and then weakening their walls so that blood leaks through.

A fifth of those patients reach hospitals but die within 48 hours, the time it takes for parasite-killing drugs to work, said Ana Rodriguez, a parasitologist at NYU Langone and a study author.

A drug that stopped hemorrhages during that window “would buy time so they don’t die in the meanwhile, and save lives,” she said.

In the study, 82 percent of mice with cerebral malaria that were treated just with parasite-killing chloroquine died, compared with only 35 percent of those treated with chloroquine combined with irbesartan, a blood-pressure drug.

Irbesartan is sold as Avapro in the United States, where it costs about $4.50 per pill. But generic versions are made in India for as little as 11 cents per pill, and a malaria patient would need only a few, Dr. Rodriguez said.